CONTENTS

SECTION 1 GENERAL

Group 1 Safety Hints -------------------------------------------------------------------------------------------------------- 1-1

Group 2 Specifications ----------------------------------------------------------------------------------------------------- 1-10
Group 3 Operational Checkout Record Sheet --------------------------------------------------------------- 1-25

SECTION 2 ENGINE

Group 1 Structure and Function -------------------------------------------------------------------------------------- 2-1

Group 2 Engine Speed and Stall rpm ----------------------------------------------------------------------------- 2-7
Group 3 Fuel Warmer System ----------------------------------------------------------------------------------------- 2-8

SECTION 3 POWER TRAIN SYSTEM

Group 1 Structure and Function -------------------------------------------------------------------------------------- 3-1

Group 2 Operational Checks and Troubleshooting ------------------------------------------------------- 3-61
Group 3 Test and Adjustments ---------------------------------------------------------------------------------------- 3-72
Group 4 Disassembly and Assembly ----------------------------------------------------------------------------- 3-74
-
SECTION 4 BRAKE SYSTEM

Group 1 Structure and Function -------------------------------------------------------------------------------------- 4-1

Group 2 Operational Checks and Troubleshooting ------------------------------------------------------- 4-21
Group 3 Tests and Adjustments -------------------------------------------------------------------------------------- 4-28
Group 4 Disassembly and Assembly ------------------------------------------------------------------------------ 4-31

SECTION 5 STEERING SYSTEM

Group 1 Structure and Function -------------------------------------------------------------------------------------- 5-1

Group 2 Operational Checks and Troubleshooting ------------------------------------------------------- 5-11
Group 3 Tests and Adjustments -------------------------------------------------------------------------------------- 5-17
Group 4 Disassembly and Assembly ----------------------------------------------------------------------------- 5-23

SECTION 6 WORK EQUIPMENT

Group 1 Structure and Function -------------------------------------------------------------------------------------- 6-1

Group 2 Operational Checks and Troubleshooting ------------------------------------------------------- 6-40
Group 3 Tests and Adjustments -------------------------------------------------------------------------------------- 6-50
Group 4 Disassembly and Assembly ----------------------------------------------------------------------------- 6-65
SECTION 7 ELECTRICAL SYSTEM

Group 1 Component Location --------------------------------------------------------------------------------------- 7-1

Group 2 Electrical Circuit ----------------------------------------------------------------------------------------------- 7-3
Group 3 Monitoring System ------------------------------------------------------------------------------------------ 7-21
Group 4 Electrical Component Specification --------------------------------------------------------------- 7-51
Group 5 Connectors ------------------------------------------------------------------------------------------------------- 7-58
Group 6 Troubleshooting ------------------------------------------------------------------------------------------------ 7-78
 FOREWORD

1. STRUCTURE
This service manual has been prepared as an aid to improve the quality of repairs by giving the
serviceman an accurate understanding of the product and by showing him the correct way to
perform repairs and make judgements. Make sure you understand the contents of this manual and
use it to full effect at every opportunity.
This service manual mainly contains the necessary technical information for operations performed in
a service workshop.
For ease of understanding, the manual is divided into the following sections.

Structure and function

This group explains the structure and function of each component. It serves not only to give an
understanding of the structure, but also serves as reference material for troubleshooting.
Operational checks and troubleshooting
This group explains the system operational checks and troubleshooting charts correlating problem to
remedy.
Tests and adjustments
This group explains checks to be amide before and after performing repairs, as well as adjustments
to be made at completion of the checks and repairs.
Disassembly and assembly
This section explains the order to be followed when removing, installing, disassembling or
assembling each component, as well as precautions to be taken for these operations.

The specifications contained in this shop manual are subject to change at any time and without any
advance notice. Contact your Hyundai distributor for the latest information.

0-1
2. HOW TO READ THE SERVICE MANUAL
Distribution and updating Revised edition mark (①②③…)
Any additions, amendments or other changes When a manual is revised, an edition mark is
will be sent to HYUNDAI distributors. recorded on the bottom outside corner of the
Get the most up-to-date information before you pages.
start any work.
Revisions
Filing method Revised pages are shown at the list of revised
1. See the page number on the bottom of the pages on the between the contents page and
page. section 1 page.
File the pages in correct order.
2. Following examples shows how to read the Symbols
page number. So that the shop manual can be of ample
Example 1 practical use, important places for safety and
3-3 quality are marked with the following symbols.
Section number (3. Power train
system)
Consecutive page number for Symbol Item Remarks
each section.
Special safety precautions are
3. Additional pages : Additional pages are necessary when performing the
indicated by a hyphen(-) and number after the work.
Safety
page number. File as in the example. Extra special safety precautions
10 - 4 are necessary when performing
10 - 4 - 1 the work because it is under
Added pages internal pressure.
10 - 4 - 2
10 - 5 Special technical precautions or

※ Caution
other precautions for preserving
standards are necessary when
performing the work.

0-2
 3. CONVERSION TABLE
Method of using the Conversion Table
The Conversion Table in this section is provided to enable simple conversion of figures. For details of
the method of using the Conversion Table, see the example given below.

Example
1. Method of using the Conversion Table to convert from millimeters to inches
Convert 55 mm into inches.
(1) Locate the number 50 in the vertical column at the left side, take this as ⓐ, then draw a horizontal
line from ⓐ.
(2) Locate the number 5in the row across the top, take this as ⓑ, then draw a perpendicular line
down from ⓑ.
(3) Take the point where the two lines cross as ⓒ. This point ⓒ gives the value when converting
from millimeters to inches. Therefore, 55 mm = 2.165 inches.

2. Convert 550 mm into inches.

(1) The number 550 does not appear in the table, so divide by 10 (move the decimal point one place
to the left) to convert it to 55 mm.
(2) Carry out the same procedure as above to convert 55 mm to 2.165 inches.
(3) The original value (550 mm) was divided by 10, so multiply 2.165 inches by 10 (move the decimal
point one place to the right) to return to the original value.
This gives 550 mm = 21.65 inches.

Millimeters to inches ⓑ
1mm = 0.03937 in

0 1 2 3 4 5 6 7 8 9

0 0.039 0.079 0.118 0.157 0.197 0.236 0.276 0.315 0.354

10 0.394 0.433 0.472 0.512 0.551 0.591 0.630 0.669 0.709 0.748
20 0.787 0.827 0.866 0.906 0.945 0.984 1.024 1.063 1.102 1.142
30 1.181 1.220 1.260 1.299 1.339 1.378 1.417 1.457 1.496 1.536
40 1.575 1.614 1.654 1.693 1.732 1.772 1.811 1.850 1.890 1.929
ⓒ
50 1.969 2.008 2.047 2.087 2.126 2.165 2.205 2.244 2.283 2.323
ⓐ
60 2.362 2.402 2.441 2.480 2.520 2.559 2.598 2.638 2.677 2.717
70 2.756 2.795 2.835 2.874 2.913 2.953 2.992 3.032 3.071 3.110
80 3.150 3.189 3.228 3.268 3.307 3.346 3.386 3.425 3.465 3.504
90 3.543 3.583 3.622 3.661 3.701 3.740 3.780 3.819 3.858 3.898

0-3
Millimeters to inches 1mm = 0.03937in

0 1 2 3 4 5 6 7 8 9

0 0.039 0.079 0.118 0.157 0.197 0.236 0.276 0.315 0.354

10 0.394 0.433 0.472 0.512 0.551 0.591 0.630 0.669 0.709 0.748
20 0.787 0.827 0.866 0.906 0.945 0.984 1.024 1.063 1.102 1.142
30 1.181 1.220 1.260 1.299 1.339 1.378 1.417 1.457 1.496 1.536
40 1.575 1.614 1.654 1.693 1.732 1.772 1.811 1.850 1.890 1.929

50 1.969 2.008 2.047 2.087 2.126 2.165 2.205 2.244 2.283 2.323
60 2.362 2.402 2.441 2.480 2.520 2.559 2.598 2.638 2.677 2.717
70 2.756 2.795 2.835 2.874 2.913 2.953 2.992 3.032 3.071 3.110
80 3.150 3.189 3.228 3.268 3.307 3.346 3.386 3.425 3.465 3.504
90 3.543 3.583 3.622 3.661 3.701 3.740 3.780 3.819 3.858 3.898

Kilogram to Pound 1kg = 2.2046lb

0 1 2 3 4 5 6 7 8 9

0 2.20 4.41 6.61 8.82 11.02 13.23 15.43 17.64 19.84

10 22.05 24.25 26.46 28.66 30.86 33.07 35.27 37.48 39.68 41.89
20 44.09 46.30 48.50 50.71 51.91 55.12 57.32 59.5. 61.73 63.93
30 66.14 68.34 70.55 72.75 74.96 77.16 79.37 81.57 83.78 85.98
40 88.18 90.39 92.59 94.80 97.00 99.21 101.41 103.62 105.82 108.03

50 110.23 112.44 114.64 116.85 119.05 121.25 123.46 125.66 127.87 130.07
60 132.28 134.48 136.69 138.89 141.10 143.30 145.51 147.71 149.91 152.12
70 154.32 156.53 158.73 160.94 163.14 165.35 167.55 169.76 171.96 174.17
80 176.37 178.57 180.78 182.98 185.19 187.39 189.60 191.80 194.01 196.21
90 198.42 200.62 202.83 205.03 207.24 209.44 211.64 213.85 216.05 218.26

0-4
Liter to U.S. Gallon 1ℓ = 0.2642 U.S.Gal

0 1 2 3 4 5 6 7 8 9

0 0.264 0.528 0.793 1.057 1.321 1.585 1.849 2.113 2.378

10 2.642 2.906 3.170 3.434 3.698 3.963 4.227 4.491 4.755 5.019
20 5.283 5.548 5.812 6.6076 6.340 6.604 6.869 7.133 7.397 7.661
30 7.925 8.189 8.454 8.718 8.982 9.246 9.510 9.774 10.039 10.303
40 10.567 10.831 11.095 11.359 11.624 11.888 12.152 12.416 12.680 12.944

50 13.209 13.473 13.737 14.001 14.265 14.529 14.795 15.058 15.322 15.586
60 15.850 16.115 16.379 16.643 16.907 17.171 17.435 17.700 17.964 18.228
70 18.492 18.756 19.020 19.285 19.549 19.813 20.077 20.341 20.605 20.870
80 21.134 21.398 21.662 21.926 22.190 22.455 22.719 22.983 23.247 23.511
90 23.775 24.040 24.304 24.568 24.832 25.096 25.631 25.625 25.889 26.153

Liter to U.K. Gallon 1ℓ = 0.21997 U.K.Gal

0 1 2 3 4 5 6 7 8 9

0 0.220 0.440 0.660 0.880 1.100 1.320 1.540 1.760 1.980

10 2.200 2.420 2.640 2.860 3.080 3.300 3.520 3.740 3.950 4.179
20 4.399 4.619 4.839 5.059 5.279 5.499 5.719 5.939 6.159 6.379
30 6.599 6.819 7.039 7.259 7.479 7.969 7.919 8.139 8.359 8.579
40 8.799 9.019 9.239 9.459 9.679 9.899 10.119 10.339 10.559 10.778

50 10.998 11.281 11.438 11.658 11.878 12.098 12.318 12.528 12.758 12.978
60 13.198 13.418 13.638 13.858 14.078 14.298 14.518 14.738 14.958 15.178
70 15.398 15.618 15.838 16.058 16.278 16.498 16.718 16.938 17.158 17.378
80 17.598 17.818 18.037 18.257 18.477 18.697 18.917 19.137 19.357 19.577
90 19.797 20.017 20.237 20.457 20.677 20.897 21.117 21.337 21.557 21.777

0-5
kgf·m to lbf
kgf lbf·ftft 1kgf·m = 7.233lbf·ft

0 1 2 3 4 5 6 7 8 9

7.2 14.5 21.7 28.9 36.2 43.4 50.6 57.9 65.1

10 72.3 79.6 86.8 94.0 101.3 108.5 115.7 123.0 130.2 137.4
20 144.7 151.9 159.1 166.4 173.6 180.8 188.1 195.3 202.5 209.8
30 217.0 224.2 231.5 238.7 245.9 253.2 260.4 267.6 274.9 282.1
40 289.3 396.6 303.8 311.0 318.3 325.5 332.7 340.0 347.2 354.4

50 361.7 368.9 376.1 383.4 390.6 397.8 405.1 412.3 419.5 426.8
60 434.0 441.2 448.5 455.7 462.9 470.2 477.4 484.6 491.8 499.1
70 506.3 513.5 520.8 528.0 535.2 542.5 549.7 556.9 564.2 571.4
80 578.6 585.9 593.1 600.3 607.6 614.8 622.0 629.3 636.5 643.7
90 651.0 658.2 665.4 672.7 679.9 687.1 694.4 701.6 708.8 716.1

100 723.3 730.5 737.8 745.0 752.2 759.5 766.7 773.9 781.2 788.4
110 795.6 802.9 810.1 817.3 824.6 831.8 839.0 846.3 853.5 860.7
120 868.0 875.2 882.4 889.7 896.9 904.1 911.4 918.6 925.8 933.1
130 940.3 947.5 954.8 962.0 969.2 976.5 983.7 990.9 998.2 10005.4
140 1012.6 1019.9 1027.1 1034.3 1041.5 1048.8 1056.0 1063.2 1070.5 1077.7

150 1084.9 1092.2 1099.4 1106.6 1113.9 1121.1 1128.3 1135.6 1142.8 1150.0
160 1157.3 1164.5 1171.7 1179.0 1186.2 1193.4 1200.7 1207.9 1215.1 1222.4
170 1129.6 1236.8 1244.1 1251.3 1258.5 1265.8 1273.0 1280.1 1287.5 1294.7
180 1301.9 1309.2 1316.4 1323.6 1330.9 1338.1 1345.3 1352.6 1359.8 1367.0
190 1374.3 1381.5 1388.7 1396.0 1403.2 1410.4 1417.7 1424.9 1432.1 1439.4

0-6
kgf/cm2 to lbf/in2 1kgf / cm2 = 14.2233lbf / in2

0 1 2 3 4 5 6 7 8 9

14.2 28.4 42.7 56.9 71.1 85.3 99.6 113.8 128.0

10 142.2 156.5 170.7 184.9 199.1 213.4 227.6 241.8 256.0 270.2
20 284.5 298.7 312.9 327.1 341.4 355.6 369.8 384.0 398.3 412.5
30 426.7 440.9 455.1 469.4 483.6 497.8 512.0 526.3 540.5 554.7
40 568.9 583.2 597.4 611.6 625.8 640.1 654.3 668.5 682.7 696.9

50 711.2 725.4 739.6 753.8 768.1 782.3 796.5 810.7 825.0 839.2
60 853.4 867.6 881.8 896.1 910.3 924.5 938.7 953.0 967.2 981.4
70 995.6 1010 1024 1038 1053 1067 1081 1095 1109 1124
80 1138 1152 1166 1181 1195 1209 1223 1237 1252 1266
90 1280 1294 1309 1323 1337 1351 1365 1380 1394 1408

100 1422 1437 1451 1465 1479 1493 1508 1522 1536 1550
110 1565 1579 1593 1607 1621 1636 1650 1664 1678 1693
120 1707 1721 1735 1749 1764 1778 1792 1806 1821 1835
130 1849 2863 1877 1892 1906 1920 1934 1949 1963 1977
140 1991 2005 2020 2034 2048 2062 2077 2091 2105 2119

150 2134 2148 2162 2176 2190 2205 2219 2233 2247 2262
160 2276 2290 2304 2318 2333 2347 2361 2375 2389 2404
170 2418 2432 2446 2460 2475 2489 2503 2518 2532 2546
180 2560 2574 2589 5603 2617 2631 2646 2660 2674 2688

200 2845 2859 2873 2887 2901 2916 2930 2944 2958 2973
210 2987 3001 3015 3030 3044 3058 3072 3086 3101 3115
220 3129 3143 3158 3172 3186 3200 3214 3229 3243 3257
230 3271 3286 3300 3314 3328 3343 3357 3371 3385 3399
240 3414 3428 3442 3456 3470 3485 3499 3513 3527 3542

0-7
TEMPERATURE
Fahrenheit-Centigrade Conversion.
A simple way to convert a fahrenheit temperature reading into a centigrade temperature reading or vice verse
is to enter the accompanying table in the center or boldface column of figures.
These figures refer to the temperature in either Fahrenheit or Centigrade degrees.
If it is desired to convert from Fahrenheit to Centigrade degrees, consider the center column as a table of
Fahrenheit temperatures and read the corresponding Centigrade temperature in the column at the left.
If it is desired to convert from Centigrade to Fahrenheit degrees, consider the center column as a table of
Centigrade values, and read the corresponding Fahrenheit temperature on the right.

˚C ˚F ˚C ˚F ˚C ˚F ˚C ˚F
-40.4 -40 -40.0 -11.7 11 51.8 7.8 46 114.8 27.2 81 117.8
-37.2 -35 -31.0 -11.1 12 53.6 8.3 47 116.6 27.8 82 179.6
-34.4 -30 -22.0 -10.6 13 55.4 8.9 48 118.4 28.3 83 181.4
-31.7 -25 -13.0 -10.0 14 57.2 9.4 49 120.2 28.9 84 183.2
-28.9 -20 -4.0 -9.4 15 59.0 10.0 50 122.0 29.4 85 185.0

-28.3 -19 -2.2 -8.9 16 60.8 10.6 51 123.8 30.0 86 186.8

-27.8 -18 -0.4 -8.3 17 62.6 11.1 52 125.6 30.6 87 188.6
-27.2 -17 1.4 -7.8 18 64.4 11.7 53 127.4 31.1 88 190.4
-26.7 -16 3.2 -6.7 20 68.0 12.8 55 131.0 32.2 90 194.0
-26.1 -15 5.0 -6.7 20 68.0 12.8 55 131.0 32.2 90 194.0

-25.6 -14 6.8 -6.1 21 69.8 13.3 56 132.8 32.8 91 195.8

-25.0 -13 8.6 -5.6 22 71.6 13.9 57 134.6 33.3 92 197.6
-24.4 -12 10.4 -5.0 23 73.4 14.4 58 136.4 33.9 93 199.4
-23.9 -11 12.2 -4.4 24 75.2 15.0 59 138.2 34.4 94 201.2
-23.3 -10 14.0 -3.9 25 77.0 15.6 60 140.0 35.0 95 203.0

-22.8 -9 15.8 -3.3 26 78.8 16.1 61 141.8 35.6 96 204.8

-22.2 -8 17.6 -2.8 27 80.6 16.7 62 143.6 36.1 97 206.6
-21.7 -7 19.4 -2.2 28 82.4 17.2 63 145.4 36.7 98 208.4
-21.1 -6 21.2 -1.7 29 84.2 17.8 64 147.2 37.2 99 210.2
-20.6 -5 23.0 -1.1 35 95.0 21.1 70 158.0 51.7 125 257.0

-20.0 -4 24.8 -0.6 31 87.8 18.9 66 150.8 40.6 105 221.0

-19.4 -3 26.6 0 32 89.6 19.4 67 152.6 43.3 110 230.0
-18.9 -2 28.4 0.6 33 91.4 20.0 68 154.4 46.1 115 239.0
-18.3 -1 30.2 1.1 34 93.2 20.6 69 156.2 48.9 120 248.0
-17.8 0 32.0 1.7 35 95.0 21.1 70 158.0 51.7 125 257.0

-17.2 1 33.8 2.2 36 96.8 21.7 71 159.8 54.4 130 266.0

-16.7 2 35.6 2.8 37 98.6 22.2 72 161.6 57.2 135 275.0
-16.1 3 37.4 3.3 38 100.4 22.8 73 163.4 60.0 140 284.0
-15.6 4 39.2 3.9 39 102.2 23.3 74 165.2 62.7 145 293.0
-15.0 5 41.0 4.4 40 104.0 23.9 75 167.0 65.6 150 302.0

-14.4 6 42.8 5.0 41 105.8 24.4 76 168.8 68.3 155 311.0

-13.9 7 44.6 5.6 42 107.6 25.0 77 170.6 71.1 160 320.0
-13.3 8 46.4 6.1 43 109.4 25.6 78 172.4 73.9 165 329.0
-12.8 9 48.2 6.7 44 111.2 26.1 79 174.2 76.7 170 338.0
-12.2 10 50.0 7.2 45 113.0 26.7 80 176.0 79.4 172 347.0

0-8
 SECTION 1 GENERAL

Group 1 Safety Hints --------------------------------------------------------------------------------------------------------1-1

Group 2 Specifications -----------------------------------------------------------------------------------------------------1-10
Group 3 Operational Checkout Record Sheet ---------------------------------------------------------------1-25
 SECTION 1 GENERAL
GROUP 1 SAFETY HINTS

FOLLOW SAFE PROCEDURE

Unsafe wor k practices are dangerous.
Understand service procedure before doing
work; Do not attempt shortcuts.

WEAR PROTECTIVE CLOTHING

Wear close fitting clothing and safety equipment
appropriate to the job.

73031GE01

WARN OTHERS OF SERVICE WORK

Unexpected machine movement can cause
serious injury.
P

Before performing any work on the wheel load-

er, attach a 「Do Do Not Operate
Operate」 tag on the
right side controller lever. WARN
DO
NOT
OPERATE
74091GE01

USE HANDHOLDS AND STEPS

Falling is one of the major causes of personal inju-
ry.
When you get on and off the machine, always
maintain a three point contact with the steps and
handrails and face the machine. Do not use any
controls as handholds.
Never jump on or off the machine. Never mount or
dismount a moving machine. 73032E01

Be careful of slippery conditions on platforms,

steps, and handrails when leaving the machine.

1-1
PREPARE FOR EMERGENCIES
Be prepared if a fire starts.
Keep a first aid kit and fire extinguisher handy.
Keep emergency numbers for doctors,
ambulance ser vice, hospital, and fire
department near your telephone.

73031GE03

WORK IN CLEAN AREA

Before starting a job :
· Clean work area and machine.
· Make sure you have all necessary tools to do
your job.
· Have the right parts on hand.
· Read all instructions thoroughly; Do not
attempt shortcuts.
73031GE26

PROTECT AGAINST FLYING DEBRIS

Guard against injury from flying pieces of metal
or debris; Wear goggles or safety glasses.

73031GE04

PROTECT AGAINST NOISE

Prolonged exposure to loud noise can cause
impairment or loss of hearing.
Wear a suitable hearing protective device such
as earmuffs or earplugs to protect against
objectionable or uncomfortable loud noises.

73031GE05

1-2
PARK MACHINE SAFELY
Before working on the machine:
· Park machine on a level surface.
· Lower bucket to the ground.
· Turn key switch to OFF to stop engine.
Remove key from switch.
· Move pilot control shutoff lever to locked
position.
· Allow engine to cool. 73031GE23

SUPPORT MACHINE PROPERLY

Always lower the attachment or implement to
the ground before you work on the machine. If
you must work on a lifted machine or attachment,
securely support the machine or attachment.
Do not support the machine on cinder blocks,
hollow tiles, or props that may crumble under
continuous load.
Do not work under a machine that is supported
solely by a jack. Follow recommended
procedures in this manual. 73031GE06

SERVICE COOLING SYSTEM SAFELY

Explosive release of fluids from pressurized
cooling system can cause serious burns.
Shut off engine. Only remove filler cap when
cool enough to touch with bare hands.

73031GE07

HANDLE FLUIDS SAFELY-AVOID FIRES

Handle fuel with care; It is highly flammable.
Do not refuel the machine while smoking or
when near open flame or sparks. Always stop
engine before refueling machine.
Fill fuel tank outdoors.

73031GE08

1-3
Store flammable fluids away from fire hazards.
Do not incinerate or puncture pressurized
containers.
Make sure machine is clean of trash,
grease, and debris.
Do not store oily rags ; They can ignite and
burn spontaneously.

73031GE09

BEWARE OF EXHAUST FUMES

Prevent asphyxiation. Engine exhaust fumes
can cause sickness or death.
If you must operate in a building, be positive
there is adequate ventilation. Either use an
exhaust pipe extension to remove the exhaust
fumes or open doors and windows to bring
enough outside air into the area.

REMOVE PAINT BEFORE WELDING OR

HEATING
Avoid potentially toxic fumes and dust.
Hazardous fumes can be generated when paint
is heated by welding, soldering, or using a torch.
Do all work outside or in a well ventilated area.
Dispose of paint and solvent properly.
Remove paint before welding or heating:
· If you sand or grind paint, avoid breathing the
dust. Wear an approved respirator.
· If you use solvent or paint stripper, remove
stripper with soap and water before welding.
Remove solvent or paint stripper containers
and other flammable material from area.
Allow fumes to disperse at least 15 minutes
before welding or heating. 73031GE10

1-4
ILLUMINATE WORK AREA SAFELY
Illuminate your work area adequately but safely.
Use a portable safety light for working inside or
under the machine. Make sure the bulb is
enclosed by a wire cage. The hot filament of an
accidentally broken bulb can ignite spilled fuel
or oil.

73031GE11

SERVICE MACHINE SAFELY

Tie long hair behind your head. Do not wear a
necktie, scarf, loose clothing or necklace when
you work near machine tools or moving parts.
If these items were to get caught, severe injury
could result.
Remove rings and other jewelry to prevent
electrical shorts and entanglement in moving
parts. 73031GE12

STAY CLEAR OF MOVING PARTS

Entanglements in moving parts can cause
serious injury.
To prevent accidents, use care when working
around rotating parts.

73031GE13

1-5
AVOID HIGH PRESSURE FLUIDS
Escaping fluid under pressure can penetrate the
skin causing serious injury.
Avoid the hazard by relieving pressure before
disconnecting hydraulic or other lines. Tighten
all connections before applying pressure.
Search for leaks with a piece of cardboard.
Protect hands and body from high pressure
73031GE14
fluids.
If an accident occurs, see a doctor immediately.
Any fluid injected into the skin must be
surgically removed within a few hours or
gangrene may result.

73031GE15

AVOID HEATING NEAR PRESSURIZED

FLUID LINES
Flammable spray can be generated by heating
near pressurized fluid lines, resulting in severe
burns to yourself and bystanders. Do not heat
by welding, soldering, or using a torch near
pressurized fluid lines or other flammable
materials.
Pressurized lines can be accidentally cut when
heat goes beyond the immediate flame area.
Install fire resisting guards to protect hoses or 73031GE16

other materials.

PREVENT BATTERY EXPLOSIONS

Keep sparks, lighted matches, and flame away
from the top of battery. Battery gas can
explode.
Never check battery charge by placing a metal
object across the posts. Use a volt-meter or
hydrometer.
Do not charge a frozen battery; It may explode.
73031GE17
Warm battery to 16˚C (60˚F).

1-6
PREVENT ACID BURNS
Sulfuric acid in battery electrolyte is poisonous. It
is strong enough to burn skin, eat holes in
clothing, and cause blindness if splashed into
eyes.
1. Avoid the hazard by:
2. Filling batteries in a well-ventilated area.
3. Wearing eye protection and rubber gloves.
Avoiding breathing fumes when electrolyte
is added.
4. Avoiding spilling of dripping electrolyte.
5. Use proper jump start procedure.
1. If you spill acid on yourself:
2. Flush your skin with water.
Apply baking soda or lime to help neutralize
the acid.
3. Flush your eyes with water for 10-15 minutes.
Get medical attention immediately.
1. If acid is swallowed:
2. Drink large amounts of water or milk.
Then drink milk of magnesia, beaten eggs,
or vegetable oil.
73031GE18
3. Get medical attention immediately.

USE TOOLS PROPERLY

Use tools appropriate to the work. Makeshift
tools, parts, and procedures can create safety
hazards.
Use power tools only to loosen threaded tools
and fasteners.
For loosening and tightening hardware, use the
correct size tools. Avoid bodily injury caused by
73031GE19
slipping wrenches.
Use only recommended replacement parts.
(See Parts catalogue.)

1-7
SERVICE TIRES SAFELY
Explosive separation of a tire and rim parts can
cause serious injury or death.
Do not attempt to mount a tire unless you have the
proper equipment and experience to perform the job.
Always maintain the correct tire pressure. Do not
inflate the tires above the recommended pressure.
Never weld or heat a wheel and tire assembly.
The heat can cause an increase in air pressure
resulting in a tire explosion.
Welding can structurally weaken or deform the
wheel.
When inflating tires, use a clip-on chuck and
extension hose long enough to allow you to stand
to one side and not in front of or over the tire
assembly. Use a safety cage if available.
Check wheels for low pressure, cuts, bubbles, 73031GE24

damaged rims or missing lug bolts and nuts.

USE PROPER LIFTING EQUIPMENT

Lifting heavy components incorrectly can cause
severe injury or machine damage.
Follow recommended procedure for removal and
installation of components in the manual.

73031GE25

DISPOSE OF FLUIDS PROPERLY

Improperly disposing of fluids can harm the
environment and ecology. Before draining any
fluids, find out the proper way to dispose of waste
from your local environmental agency.
Use proper containers when draining fluids. Do
not use food or beverage containers that may
mislead someone into drinking from them.
73031GE20
DO NOT pour oil into the ground, down a drain, or
into a stream, pond, or lake. Observe relevant
environmental protection regulations when
disposing of oil, fuel, coolant, brake fluid, filters,
batteries, and other harmful waste.

1-8
REPLACE SAFETY SIGNS
Replace missing or damaged safety signs.
See the machine operator's manual for correct
safety sign placement.

73031GE21

LIVE WITH SAFETY

Before returning machine to customer, make
sure machine is functioning properly, especially
the safety systems. Install all guards and
shields.

K E E P RO P S I N S TA L L E D P RO P E R LY
(option)
Make certain all parts are reinstalled correctly if
the roll-over protective structure (ROPS) is
loosened or removed for any reason. Tighten
mounting bolts to proper torque.
The protection offered by ROPS will be
impaired if ROPS is subjected to structural
damage, is involved in an overturn incident, or is
in any way altered by welding, bending, drilling, 73031GE22
or cutting. A damaged ROPS should be
replaced, not reused.

1-9
GROUP 2 SPECIFICATION

1. MAJOR COMPONENTS

Bucket Tire Head light Hydraulic tank Radiator

Boom Boom cylinder Main control valve Battery Counterweight

Bell crank Bucket cylinder Cab Main pump Air cleaner Muffler

Bucket link Front axle Steering cylinder Transmission Rear axle Engine Fuel tank

7309S2SP05

1-10
2. SPECIFICATIONS
1) WITH BOLT-ON CUTTING EDGE TYPE BUCKET (HL730-9S)

F
B

I
J

4790
H

3640

C
40

G
K
47
0
551 0

D
0
E
A
7309S2SP01

Description Unit Specification

Operating weight kg (lb) 9700 (21400)
Struck 1.5 (2.0)
Bucket capacity m3 (yd3)
Heaped 1.8 (2.4)
Overall length A 6900 (22' 8")
Overall width B 2450 (8' 0")
Overall height C 3190 (10' 6")
Ground clearance D 370 (1' 3")
Wheelbase E mm (ft-in) 2750 (9' 0")
Tread F 1850 (6' 0")
Dump clearance at 45˚ G 2730 (8' 11")
Dump reach (full lift) H 1005 (3' 4")
Width over tires I 2295 (7' 6")
Dump angle J 48
degree (˚)
Roll back angle (carry position) K 48
Lift (with load) 5.6
Cycle time Dump (with load) sec 1.0
Lower (empty) 3.0
Maximum travel speed km/hr (mph) 37.0 (23.0)
Braking distance 12 (39' 4")
m (ft-in)
Minimum turning radius (center of outside tire) 4.7 (15' 5")
Gradeability degree (˚) 30
Brakeout force kg (lb) 9590 (21140)
First gear 6.0 (3.7)
Second gear 11.0 (6.8)
Forward
Third gear 21.8 (13.5)
Travel speed Fourth gear km/hr (mph) 37.0 (23.0)
First gear 6.3 (3.9)
Reverse Second gear 11.6 (7.2)
Third gear 23.0 (14.3)

1-11
 WITH BOLT-ON CUTTING EDGE TYPE BUCKET (HL730XTD-9S)

F
B

I
J

5120
H

3970

C
40

G
K
47
565 00

D
0
E
A

7309S2SP02

Description Unit Specification

Operating weight kg (lb) 9900 (21830)
Struck 1.5 (2.0)
Bucket capacity m3 (yd3)
Heaped 1.8 (2.4)
Overall length A 7190 (23' 7")
Overall width B 2450 (8' 0")
Overall height C 3190 (10' 6")
Ground clearance D 370 (1' 3")
Wheelbase E mm (ft-in) 2750 (9' 0")
Tread F 1850 (6' 0")
Dump clearance at 45˚ G 3036 (10' 0")
Dump reach (full lift) H 1010 (3' 4")
Width over tires I 2295 (7' 6")
Dump angle J 48
degree (˚)
Roll back angle (carry position) K 49
Lift (with load) 5.6
Cycle time Dump (with load) sec 1.0
Lower (empty) 3.0
Maximum travel speed km/hr (mph) 37.0 (23.0)
Braking distance 12 (39' 4")
m (ft-in)
Minimum turning radius (center of outside tire) 4.7 (15' 5")
Gradeability degree (˚) 30
Brakeout force kg (lb) 9520 (20990)
First gear 6.0 (3.7)
Second gear 11.0 (6.8)
Forward
Third gear 21.8 (13.5)
Travel speed Fourth gear km/hr (mph) 37.0 (23.0)
First gear 6.3 (3.9)
Reverse Second gear 11.6 (7.2)
Third gear 23.0 (14.3)

1-12
 2) WITH TOOTH TYPE BUCKET (HL730-9S)

F
B

I
J

4850
H

3640

C
40

G
K
47
00
556

D
0
E
A

73092SP03

Description Unit Specification

Operating weight kg (lb) 9700 (21400)
Struck 1.4 (1.9)
Bucket capacity m3 (yd3)
Heaped 1.7 (2.2)
Overall length A 7000 (23' 0")
Overall width B 2480 (8' 2")
Overall height C 3190 (10' 6")
Ground clearance D 370 (1' 3")
Wheelbase E mm (ft-in) 2750 (9' 0")
Tread F 1850 (6' 0")
Dump clearance at 45˚ G 2640 (8' 8")
Dump reach (full lift) H 1075 (3' 6")
Width over tires I 2295 (7' 6")
Dump angle J 48
degree (˚)
Roll back angle (carry position) K 48
Lift (with load) 5.6
Cycle time Dump (with load) sec 1.0
Lower (empty) 3.0
Maximum travel speed km/hr (mph) 37.0 (23.0)
Braking distance 12 (39' 4")
m (ft-in)
Minimum turning radius (center of outside tire) 4.7 (15' 5")
Gradeability degree (˚) 30
Brakeout force kg (lb) 10320 (22750)
First gear 6.0 (3.7)
Second gear 11.0 (6.8)
Forward
Third gear 21.8 (13.5)
Travel speed Fourth gear km/hr (mph) 37.0 (23.0)
First gear 6.3 (3.9)
Reverse Second gear 11.6 (7.2)
Third gear 23.0 (14.3)

1-13
 WITH TOOTH TYPE BUCKET (HL730XTD-9S)

F
B

I
J

5190
H

3980

C
40

G
K
47
566 00

D
5

73092SP04

Description Unit Specification

Operating weight kg (lb) 9900 (21830)
Struck 1.4 (1.9)
Bucket capacity m3 (yd3)
Heaped 1.7 (2.2)
Overall length A 7350 (24' 1")
Overall width B 2480 (8' 2")
Overall height C 3190 (10' 6")
Ground clearance D 370 (1' 3")
Wheelbase E mm (ft-in) 2750 (9' 0")
Tread F 1850 (6' 0")
Dump clearance at 45˚ G 2970 (9' 9")
Dump reach (full lift) H 1090 (3' 7")
Width over tires I 2295 (7' 6")
Dump angle J 48
degree (˚)
Roll back angle (carry position) K 49
Lift (with load) 5.6
Cycle time Dump (with load) sec 1.0
Lower (empty) 3.0
Maximum travel speed km/hr (mph) 37.0 (23.0)
Braking distance 12 (39' 4")
m (ft-in)
Minimum turning radius (center of outside tire) 4.7 (15' 5")
Gradeability degree (˚) 30
Brakeout force kg (lb) 10250 (22600)
First gear 6.0 (3.7)
Second gear 11.0 (6.8)
Forward
Third gear 21.8 (13.5)
Travel speed Fourth gear km/hr (mph) 37.0 (23.0)
First gear 6.3 (3.9)
Reverse Second gear 11.6 (7.2)
Third gear 23.0 (14.3)

1-14
3. WEIGHT

Item kg lb
Front frame assembly 814 1800
Rear frame assembly 1057 2330
Front fender (LH & RH) 31 68
HL730-9S 350 770
Counterweight
HL730XTD-9S 450 990
Cab assembly 700 1540
Engine assembly 371 818
Transmission assembly 399 880
Drive shaft (front) 17 37
Drive shaft (center) 16 35
Drive shaft (rear) 11 24
Drive shaft (upper) 7 15
Front axle (include differential) 545 1200
Rear axle (include differential) 540 1190
Tire (17.5-25, 12PR, L3) 130 290
Hydraulic tank assembly 147 324
Fuel tank assembly 282 622
Main pump assembly 26 57
Fan & brake pump assembly 7 15
Main control valve (2 / 3 spool) 34/41 75/90
HL730-9S 540 1190
Boom assembly
HL730XTD-9S 620 1370
Bell crank assembly 140 310
Bucket link 29.5 65
1.8 m3 bucket, with bolt on cutting edge 780 1720
1.7 m3 bucket, with tooth 710 1570
Boom cylinder assembly 70 150
Bucket cylinder assembly 78 170
Steering cylinder assembly 15 30
Seat 40 88
Battery 28 62

1-15
4. SPECIFICATION FOR MAJOR COMPONENTS
1) ENGINE
Item Specification
Model Cummins QSB4.5
Type 4-cycle turbocharged and charge air-cooled diesel engine.
Cooling method Water cooling
Number of cylinders and arrangement 4 cylinders, in-line
Firing order 1-3-2-4
Combustion chamber type Direct injection type
Cylinder bore × stroke 107×124 mm (4.2"×4.9")
Piston displacement 4500 cc (275 cu in)
Compression ratio 17.2 : 1
Rated gross horse power 125 hp at 2100 rpm
Maximum gross torque at 1400rpm 56 kgf·m (408 lbf·ft)
Engine oil quantity 11ℓ(2.9 U.S. gal)
Dry weight 371 kg (818 lb)
High idling speed 2230±50rpm
Low idling speed 950±25 rpm
Rated fuel consumption (at rated) 237 g/kw·hr
Starting motor Nippondenso 228000-7902 (24 V-3.7 kW)
Alternator Delco Remy 24SI (24V-70Amp)
Battery 2×12V×100Ah

1-16
 2) MAIN PUMP
Item Specification
Type Fixed displacement tandem gear pump
Capacity 36+32.3 cc/rev
Maximum operating pressure 210 kgf/cm2 (2990 psi)
Rated output flow 138ℓ/min (36.5 U.S.gpm)

3) FAN AND BRAKE PUMP

Specification
Item
Fan Brake
Type Fixed displacement tandem gear pump
Capacity 9.17 cc/rev 9.17 cc/rev
Maximum operating pressure 120 kgf/cm2 (1710 psi) 150 kgf/cm2 (2130 psi)
Rated output flow 19ℓ/min (5.0 U.S.gpm) 19ℓ/min (5.0 U.S.gpm)

4) MAIN CONTROL VALVE

Item Specification
Type 2 spool
Operating method Hydraulic pilot assist
Main relief valve set pressure 210 kgf/cm2 (2990 psi)
Overload relief valve set pressure 240 kgf/cm2 (3410 psi)

5) REMOTE CONTROL VALVE

Item Specification
Type Joystick (or with aux lever)
Minimum 3.7 kgf/cm2 (52.6 psi)
Control pressure
Maximum 30 kgf/cm2 (427 psi)

6) CYLINDER
Item Specification
Boom cylinder Bore dia×Rod dia×Stroke Ø105×Ø65×772 mm
Bucket cylinder Bore dia×Rod dia×Stroke Ø120×Ø70×510 mm
Steering cylinder Bore dia×Rod dia×Stroke Ø 60×Ø35×412 mm

1-17
7) DYNAMIC POWER TRANSMISSION DEVICES

Item Specification
Model ZF 4WG130
Torque converter Type Single-stage, single-phase
Ratio 1.87 : 1
Type Full-automatic power shift
Gear shift Forward fourth gear, reverse third gear
Transmission
Control Electrical single lever type, kick-down system
Pump rated flow 85ℓ/min (22.5 U.S.gpm) at 2000 rpm
Drive devices 4-wheel drive
Axle Front Front fixed location
Rear Oscillation±12˚ of center pin-loaded
Wheels Tires 17.5-25, 12PR (L3)
Travel Four-wheel, wet-disc type, full hydraulic
Brakes
Parking Spring applied, hydraulic released brake on front axle
Type Full hydraulic, articulated
Steering
Steering angle 40˚ to both right and left angle, respectively

1-18
5. TIGHTENING TORQUE OF MAJOR COMPONENT
Torque
No. Descriptions Bolt size
kgf·m lbf·ft
1 Engine mounting bolt, nut (rubber, 4EA) M16×2.0 29.7 ± 4.5 215 ± 32.5
2 Engine mounting bolt (bracket) M12×1.75 10.7 ± 1.6 77.4 ± 11.6
3 Radiator mounting bolt M16×2.0 29.7 ± 4.5 215 ± 32.5
Engine
4 Fuel tank mounting bolt, nut M16×2.0 29.7 ± 4.5 215 ± 32.5
5 Air cleaner mounting bolt M 8×1.5 2.5 ± 0.5 18.1 ± 3.6
6 Muffler mounting nut M12×1.75 10.7 ± 1.6 77.4 ± 11.6
7 Main pump housing mounting bolt M14×2.0 19.6 ± 2.9 142 ± 20.9
8 Main control valve mounting bolt M12×1.75 12.8 ± 3.0 92.6 ± 21.7
9 Steering unit mounting bolt M10×1.5 6.9 ± 1.4 49.9 ± 10.1
10 Priority valve M 8×1.25 2.5 ± 0.5 18.1 ± 3.6
11 Brake valve mounting bolt M 8×1.25 2.5 ± 0.5 18.1 ± 3.6
Hydraulic
12 Fan and brake pump mounting bolt M10×1.5 6.9 ± 1.4 49.9 ± 10.1
system
13 Cut-off valve mounting bolt M12×1.75 12.8 ± 3.0 92.6 ± 21.7
14 Remote control lever mounting bolt M 6×1.0 1.1 ± 0.2 8.0 ± 1.4
15 Pilot supply unit mounting bolt M 8×1.25 2.5 ± 0.5 18.1 ± 3.6
16 Safety valve M 8×1.25 2.5 ± 0.5 18.1 ± 3.6
17 Hydraulic oil tank mounting bolt M16×2.0 29.7 ± 4.5 215 ± 32.5
18 Transmission mounting bolt, nut (rubber, 4EA) M20×2.5 57.9 ± 8.7 419 ± 63
19 Transmission mounting bolt (bracket, T/C side) M16×2.0 18.4 ± 2.0 133 ± 14.5
20 Transmission mounting bolt (bracket, output side) M20×2.5 57.9 ± 8.7 419 ± 63
Power
21 train Front axle mounting bolt, nut M24×2.0 100 ± 15 723 ± 108
system
22 Rear axle support mounting bolt, nut M24×2.0 100 ± 15 723 ± 108
23 Tire mounting nut M22×1.5 79 ± 2.5 571 ± 18.1
24 Drive shaft joint mounting bolt, nut 3/8-24UNF 2.8 ± 0.4 20.3 ± 2.9
25 Counterweight mounting bolt M30×3.5 199 ± 30 1439 ± 216
26 Operator's seat mounting bolt M8×1.25 3.4 ± 0.8 24.6 ± 5
27 Others Cab mounting bolt (4EA) M20×2.5 58 ± 8.7 419 ± 63
28 Cab mounting nut (4EA) M16×2.0 29.7 ± 4.5 215 ± 32.5
29 Cab mounting bolt (bumper, 16EA)) M10×1.5 6.9 ± 1.4 49.9 ± 10.1

1-19
6. TORQUE CHART

Use following table for unspecified torque.

1) BOLT AND NUT

(1) Coarse thread

8T 10T
Bolt size
kg·m lb·ft kg·m lb·ft
M 6×1.0 0.85 ~ 1.25 6.15 ~ 9.04 1.14 ~ 1.74 8.2 ~ 12.6
M 8×1.25 2.0 ~ 3.0 14.5 ~ 21.7 2.73 ~ 4.12 19.5 ~ 29.8
M10×1.5 4.0 ~ 6.0 28.9 ~ 43.4 5.5 ~ 8.3 39.8 ~ 60
M12×1.75 7.4 ~ 11.2 53.5 ~ 79.5 9.8 ~ 15.8 71 ~ 114
M14×2.0 12.2 ~ 16.6 88.2 ~ 120 16.7 ~ 22.5 121 ~ 167
M16×2.0 18.6 ~ 25.2 135 ~ 182 25.2 ~ 34.2 182 ~ 247
M18×2.5 25.8 ~ 35.0 187 ~ 253 35.1 ~ 47.5 254 ~ 343
M20×2.5 36.2 ~ 49.0 262 ~ 354 49.2 ~ 66.6 356 ~ 482
M22×2.5 48.3 ~ 63.3 350 ~ 457 65.8 ~ 98.0 476 ~ 709
M24×3.0 62.5 ~ 84.5 452 ~ 611 85.0 ~ 115 615 ~ 832
M30×3.0 124 ~ 168 898 ~ 1214 169 ~ 229 1223 ~ 1655
M36×4.0 174 ~ 236 1261 ~ 1703 250 ~ 310 1808 ~ 2242

(2) Fine thread

8T 10T
Bolt size
kg·m lb·ft kg·m lb·ft
M 8×1.0 2.17 ~ 3.37 15.7 ~ 24.3 3.04 ~ 4.44 22.0 ~ 32.0
M10×1.25 4.46 ~ 6.66 32.3 ~ 48.2 5.93 ~ 8.93 42.9 ~ 64.6
M12×1.25 7.78 ~ 11.58 76.3 ~ 83.7 10.6 ~ 16.0 76.6 ~ 115
M14×1.5 13.3 ~ 18.1 96.2 ~ 130 17.9 ~ 24.1 130 ~ 174
M16×1.5 19.9 ~ 26.9 144 ~ 194 26.6 ~ 36.0 193 ~ 260
M18×1.5 28.6 ~ 43.6 207 ~ 315 38.4 ~ 52.0 278 ~ 376
M20×1.5 40.0 ~ 54.0 289 ~ 390 53.4 ~ 72.2 386 ~ 522
M22×1.5 52.7 ~ 71.3 381 ~ 515 70.7 ~ 95.7 512 ~ 692
M24×2.0 67.9 ~ 91.9 491 ~ 664 90.9 ~ 123 658 ~ 890
M30×2.0 137 ~ 185 990 ~ 1338 182 ~ 248 1314 ~ 1795
M36×3.0 192 ~ 260 1389 ~ 1879 262 ~ 354 1893 ~ 2561

1-20
2) PIPE AND HOSE (FLARE type)
Thread size Width across flat (mm) kgf·m lbf·ft

1/4" 19 4 28.9
3/8" 22 5 36.2
1/2" 27 9.5 68.7
3/4" 36 18 130
1" 41 21 152
1-1/4" 50 35 253

3) PIPE AND HOSE (ORFS type)

Thread size Width across flat (mm) kgf·m lbf·ft

9/16-18 19 4 28.9
11/16-16 22 5 36.2
13/16-16 27 9.5 68.7
1-3/16-12 36 18 130
1-7/16-12 41 21 152
1-11/16-12 50 35 253

4) FITTING

Thread size Width across flat (mm) kgf·m lbf·ft

1/4" 19 4 28.9
3/8" 22 5 36.2
1/2" 27 9.5 68.7
3/4" 36 18 130
1" 41 21 152
1-1/4" 50 35 253

1-21
7. RECOMMENDED LUBRICANTS
Use only oils listed below or equivalent.
Do not mix different brand oil.
Ambient temperature˚C (˚F)
Capacity
Service point Kind of fluid -20 -10 0 10 20 30 40
ℓ (U.S. gal)
(-4) (14) (32) (50) (68) (86) (104)

SAE 30

SAE 10W
Engine oil pan Engine oil 11 (2.9)
SAE 10W-30

SAE 15W-40

SAE 10W-30
Transmission Engine oil 20 (5.3)
SAE 15W-40

Front : 17.7 (4.7)

Axle Gear oil SAE80W-90LS/API GL-5
Rear : 17.7 (4.7)

ISO VG 32
Tank:
92 (24.3)
Hydraulic tank Hydraulic oil ISO VG 46
System:
134.5 (35.5)
ISO VG 68

ASTM D975 NO.1

Fuel tank Diesel fuel 200 (52.8)
ASTM D975 NO.2

NLGI NO.1
Fitting
Grease As required
(grease nipple) NLGI NO.2

Mixture of
antifreeze Ethylene glycol base permanent type
Radiator 30 (7.9)
and water
50 : 50

·SAE : Society of Automotive Engineers ·NLGI : National Lubricating Grease Institute

·API : American Petroleum Institute ·ASTM : American Society of Testing and Material
·ISO : International Organization for Standardization

1-22
 GROUP 3 OPERATIONAL CHECKOUT RECORD SHEET

·Owner :
·Date :
·Hours :
·Serial No. :
·Technician :

※ Use this sheet to record operational

checkout results.
Perform the operational check before
installing any test equipment. 73091GE02

OK NOT
Item Comments
OK

1. Monitor indicator and gauge checks (engine OFF)

· Hourmeter and gauge check □ □

· Battery check □ □
· Monitor indicator circuit check □ □
· Cluster turn signals and warning indicator check □ □

2. Transmission, axle and engine, neutral start

switch and reverse warning alarm switch checks

· Transmission control lever and neutral □ □

· Neutral start and reverse warning □ □
· Alarm circuit checks □ □

3. Monitor indicator and gauge checks (engine running)

· Monitor display and alternator output checks □ □

· Monitor bypass circuit and seat belt indicator check □ □
· Monitor primary and secondary level check □ □
· Transmission oil warm up procedure □ □
· Transmission temperature gauge check □ □

1-23
4. Brake system and clutch cut off checks

· Park brake capacity check □ □

· Park brake transmission lockout check □ □
· Service brake pump flow check □ □
· Service brake capacity check □ □
· Brake accumulator precharge check □ □
· Brake system leakage check □ □
· Service brake pedal check □ □
· Service and park brake system drag check □ □
· Clutch cut off check □ □

5. Driving checks

·Transmission oil warm up procedure □ □

·Transmission noise check □ □
·Speedometer check □ □
·Transmission kick down system check □ □
·1st, 2nd, 3rd and 4th speed clutch pack drag check □ □
·Transmission pressure, pump flow and leakage check □ □
·Transmission shift modulation check □ □
·Torque converter check □ □
·Engine power check □ □

6. Hydraulic system checks

·Hydraulic system warm up procedure □ □

·Hydraulic pump performance check □ □
·Pilot control valve boom float check □ □
·Boom down solenoid valve check □ □
·Control valve lift check □ □
·Bucket rollback circuit relief valve check □ □
·Bucket dump circuit relief
Low pressure check □ □
High pressure check □ □
·Boom and bucket cylinder drift check □ □
·Boom down solenoid valve leakage check □ □
·Pilot controller check □ □
·Return to dig check □ □
·Boom height kickout check-if equipped □ □

1-24
7. Steering system checks

·Steering unit check □ □

·Steering system leakage check □ □
·Steering valve (EHPS)
Low check pressure □ □
High check pressure □ □

8. Accessory checks

·Operating lights check □ □

·Work light check □ □
·Brake light check □ □
·Cab light check □ □
·Horn circuit check □ □
·Windshield washer and wiper check □ □
·Defroster blower check □ □
·Heater/Air conditioner blower check □ □
·Heater functional check □ □
·Air conditioner functional check □ □
·Start aid system check □ □

9. Cab components and vandal protection checks

·Cab door latch check □ □

·Cab door hold open latch check □ □
·Cab door release button check □ □
·Cab door lock check □ □
·Cab door window check □ □
·Cab window latch check □ □
·Steering column adjustment check □ □
·Seat and seat belt check □ □
·Air intake filter door check □ □
·Engine side panels check □ □
·Radiator cap access door check □ □
·Frame locking bar check □ □
·Boom lock check □ □
·Service decal check □ □

1-25
 SECTION 2 ENGINE

Group 1 Structure and Function -------------------------------------------------------------------------------------- 2-1

Group 2 Engine speed and Stall rpm ----------------------------------------------------------------------------- 2-7
Group 3 Fuel warmer system ------------------------------------------------------------------------------------------ 2-8
 SECTION 2 ENGINE
GROUP 1 STRUCTURE AND FUNCTION

1. STRUCTURE

Turbocharger Exhaust outlet connection

Coolant heater starting aid

Alternator

Starting motor Lubricating oil filter

Water inlet
connection
Flywheel housing

Engine oil cooler

Air intake connection Lifting bracket

Fuel filter
Fan pilot spacer
Engine control
module(ECM)

Fuel pump

Front engine support

Oil pan

7307AEG01

· Direct 4-stroke, 4-cylinders, water-cooling and charge air cooled diesel engine in installed, cylinder
block and cylinder head are made of case iron and turbocharger is attached.

2-1
2. SYSTEM DIAGRAMS
The following drawings show the flow through the engine systems.

1) FUEL SYSTEM

7607AEG02

1 From fuel tank 11 Fuel rail

2 Water/fuel separator (not mounted on engine) 12 To injectors
3 ECM cooling plate 13 High-pressure connector
4 To fuel gear pump 14 Injector
5 To fuel filter 15 Fuel return from injectors and fuel rail to fuel
6 Fuel filter head filter head
7 Fuel filter 16 Fuel return from high-pressure pump to fuel
8 To high-pressure pump filter head
9 High-pressure pump 17 To fuel tank
10 To fuel rail

2-2
 2) LUBRICATING OIL SYSTEM

7607AEG03

1 Gerotor lubricating oil pump 8 Filter bypass valve

2 From lubricating oil pump 9 Filter bypass valve closed
3 Pressure regulating valve closed 10 Filter bypass valve open
4 Pressure regulating valve open 11 To lubricating oil filter
5 To lubricating oil cooler 12 Full-flow lubricating oil filter
6 To lubricating oil pump supply 13 From lubricating oil filter
7 Lubricating oil cooler 14 Main lubricating oil rifle

(1) Lubrication for the turbocharger

7607AEG04

1 Turbocharger lubricating oil supply 2 Turbocharger lubricating oil drain

2-3
(2) Lubrication for the power components

7607AEG05

1 From lubricating oil cooler 6 To camshaft

2 Main lubricating oil rifle 7 Crankshaft main journal
3 To valve train 8 Oil supply to rod bearings
4 From main lubricating oil rifle 9 Directed piston-cooling nozzle
5 To piston-cooling nozzle 10 To internal lubrication of air compressor

(3) Lubrication for the overhead

7607AEG06

1 Main lubricating oil rifle 4 Rocker lever shaft

2 Rocker lever support 5 Rocker lever bore
3 Transfer slot 6 Rocker lever

2-4
 3) COOLING SYSTEM

7607AEG07

1 Coolant inlet 7 Coolant flow to thermostat housing

2 Pump lmpeller 8 Coolant bypass passage
3 Coolant flow past lubricating oil cooler 9 Coolant flow back to radiator
4 Coolant flow past cylinders 10 Bypass closed
5 Coolant flow from cylinder block to cylinder head 11 Coolant bypass in cylinder head
6 Coolant flow between cylinders 12 Coolant flow to water pump inlet

4) AIR INTAKE SYSTEM

7607AEG08

1 Intake air inlet to turbocharger 4 Intake manifold

2 Turbocharger air to charge air cooler (Integral part of cylinder head)
3 Charge air cooler 5 Intake valve

2-5
5) EXHAUST SYSTEM

7607AEG09

1 Exhaust valve 3 Turbocharger

2 Exhaust manifold 4 Turbocharger exhaust outlet

2-6
 GROUP 2 ENGINE SPEED & STALL RPM
1. TEST
TEST CONDITION
1) Normal temperature of the whole system
- Coolant : Approx 80˚C (176˚F)
- Hydraulic oil : 45 ± 5˚C (113 ± 10˚F)
- Transmission oil : 75 ± 5˚C (167 ± 10˚F)
2) Normal operating pressure : See page 6-51.
2. SPECIFICATION
SPECIFICATION
Engine speed, rpm (P mode)
Remark
Low idle High idle Pump stall Converter stall Full stall Fan motor
950±25 2230±50 2100±70 1950±70 1530±100 1150±50

3. ENGINE
ENGINE RPM CHECK
Remark : If the checked data is not normal, it indicates that the related system is not working properly.
Therefore, it is required to check the related system pressure : See page 6-51.
1) Pump stall rpm
- Start the engine and raise the bucket
approx 45 cm (1.5 ft) as the figure.
- Press the accelerator pedal fully and
operate the bucket control lever to the
45cm

retract position fully.

- Check the engine rpm at the above
condition.
73092EG01

2) Convertor stall rpm

- Start the engine and lower the bucket on
OFF

the ground as the figure.

L

M H

- Set the clutch cut off mode switch at the Clutch cut off mode switch

OFF position.
- Press the brake pedal and accelerator
pedal fully.
- Shift the transmission lever to the 4th
forward position.
- Check the engine rpm at the above 73092EG02

condition.
3) Full stall rpm
- Start the engine and raise the bucket
OFF

approx 45 cm (1.5 ft) as the figure.

L

M H

- Set the clutch cut off mode switch at the Clutch cut off mode switch

OFF position.
- Press the brake pedal and accelerator
45cm

pedal fully .
- Shift the transmission lever to the 4th
forward position and operate the bucket
lever to the retract position fully. 73092EG03

- Check the engine rpm at the above

condition.
2-7
GROUP 3 F
FUEL
UEL WARMER SYSTEM

1. S
SPECIFICATION
PECIFICATION
1) Operating voltage : 24±4V
2) Power : 350±50W
3) Current : 15A

2. O
OPERATION
PERATION
1) T h e c u r r e n t o f f u e l w a r m e r s y s t e m i s Fuel warmer
automatically controlled without thermostat
according to fuel temperature.
2) At the first state, the 15A current flows to the fuel
warmer and engine may be started in 1~2 Prefilter
minutes.
3) If the fuel starts to flow, ceramic-disk in the fuel
warmer heater senses the fuel temperature to
reduce the current as low as 1.5A.
So, fuel is protected from overheating by this
2507A5MS12
mechanism.

3. E
ELECTRIC
LECTRIC CIRCUIT
CN-60
MASTER SW 40A
3R 104 104 3R 105 FUSE MAXI
3R 102 111 15R 106

80A
3R
15R
CN-95

CS-74 BATT. RY
80R 107 108

80R 109
BATTERY
CR-1

TO STARTER

MCU
AC COMP. OFF SIG_REVERSE FAN

SPARE_LOW_ENGINE OIL LOW

AC CONDENSOR FAN SIGNAL
SPARE_DIGITAL INPUT_LOW
SPARE_DIGITAL INPUT_LOW

BLOWER RUN SIGNAL_DINP

BUCKET POSITION SENSOR

CLUSTER 24V BATTERY
MIRROR,SER.SOCKET2

PRE-HEAT, FUEL WARMER

BOOM POSITION SENSOR

WORK LAMP_FRONT

START KEY SWITCH

SERVICE SOCKET 1

AUDIO/ROOM LAMP
HORN/CONVERTER

WORK LAMP_REAR
AIR-CON/HEATER 1

AIR-CON/HEATER 2
JOYSTICK-DETENT

MCU 24V BATTERY

ECM 24V BATTERY
TCU 24V BATTERY

SPARE_HIGH SOURCE
BACK.STOP LAMP

JOYSTIC_SWITCH
RIDE CONTROL
CIGARLIGHTER

FAN REVERSE
FUEL WARMER

TURN LAMP
HEAD LAMP

FUEL WARMER
WIPER INT SIG
ILL.LAMP
BEACON

SPARE

WIPER

CAN2 LOW
PARK
FUSE BOX

WASH SIG
CAN2 HI
CN-36
10A

20A

20A

20A

20A

10A

20A

30A

20A

30A

20A

20A

20A

20A

20A

10A

20A

20A

10A

10A

20A

30A

10A

20A

20A

20A

10A
5A

A38
B14

B15
A16
A24

B40
B30
A05
A18
A08
A23
A31

A35

A26
24

25
26
27
28
29
30
31
32
33
34
15
16
17
18
19
20
21
22
23

1
2
3
4
5
6
7
8

L 380

CN-58B

CN-5
20
21
22
CR-25 23
86 30 87a 24
B G01A
85 25
87
RW 531
ECM POWER IG 26
86 27
85 87 87a R 530
30 28
ECM POWER RY 29
40
CR-35 31
86 30 87a 32 CN-13 FUEL WARMER
B G01
85 33 1 B
Gr 550
87 MCU POWER IG 30 2 A
RW 531
86 35 3
85 87 87a R 530 CN-96
30 4
POWER RY 5
6
LW 381
Y 370A

Y 370B
H BR ACC ST C

6 7
Y 370
L 380

5 CS-2
8
6
3 5
CR-46

CR-36

2
87

30
87a
85

86

4
B

1
1
5

3
2
4

RW 531
4 3
85 8787a

R 530
0, I

1 5 4

1
H 0 I II

86 30

2 3

RW 531
2

START SWITCH FUEL WARMER RY PREHEAT RY 7579S2EG04

2-8
 SECTION 3 POWER TRAIN SYSTEM

Group 1 Structure and Function ----------------------------------------------------------------------------------- 3-1

Group 2 Operational Checks and Troubleshooting ----------------------------------------------------- 3-61
Group 3 Tests and Adjustments ----------------------------------------------------------------------------------- 3-72
Group 4 Disassembly and Assembly --------------------------------------------------------------------------- 3-74
 SECTION 3 POWER TRAIN SYSTEM
GROUP 1 STRUCTURE AND FUNCTION

1. POWER TRAIN COMPONENT OVERVIEW

Front drive shaft Upper drive shaft Engine

Front axle Center drive shaft Transmission Rear drive shaft Rear axle
73093PT01

The power train consists of the following components :

·Transmission
·Front, upper, center and rear drive shafts
·Front and rear axles
Engine power is transmitted to the transmission through the torque converter.
The transmission is a hydraulically engaged four speed forward, three speed reverse counter shaft type
power shift transmission. A disk type parking brake is located in the front axle.
The transmission outputs through universal joints to three drive shaft assemblies. The front drive shaft
is a telescoping shaft which drives the front axle. The front axle is mounted directly to the loader front
frame. The rear axle is mounted on an oscillating pivot.
The front and rear axle are equipped with conventional differential as standard (option : limited slip
differential).
The power transmitted to front axle and rear axle is reduced by the pinion gear and ring gear of
differential. It then passes from the differential to the sun gear shaft (axle shaft) of final drive.
The power of the sun gear is reduced by a planetary mechanism and is transmitted through the

3-1
 HYDRAULIC CIRCUIT

K4 KR K1 K3 KV K2

P1 F 60 P2 E 55 P3 D 56 P4 C 58 P5 B 53 P6 A 57

B D B D B D B D B D B D

Y1 NFS Y2 NFS Y3 NFS Y4 NFS Y5 NFS Y6 NFS

Pressure
Temp reducing
sensor valve
9+0.5 bar
System
pressure
Valve block control circuit valve
16+2 bar

Filter pressure
differential valve
Converter
Relief Filter
valve
11+2 bar

Oil cooler Bcak

pressure
valve Pump
Bypass 4.3+3 bar
valve 16+2 bar
3 bar

Oil sump
Lubrication Main oil circuit

7607APT18

NFS Follow-on slide P3 Proportional valve K1

D Vibration damper P4 Proportional valve K3
B Orifice P5 Proportional valve KV
P1 Proportional valve K4 P6 Proportional valve K2
P2 Proportional valve KR Y1~Y6 Pressure regulator

Current
Forward Reverse Engaged Positions No. of the
Speed Neutral on the measuring
clutch valve block
1 2 3 4 1 2 3 points
Y1 X K4 F 60
Y2 X X X KR E 55
Y3 X X X K1 D 56
Y4 X X K3 C 58
Y5 X X X KV B 53
Y6 X X K2 A 57
Engaged
K1,KV KV,K2 K3,KV K4,K3 KR,K1 KR,K2 KR, K3 - - -
clutch
X : Pressure regulator under voltage

3-2
2. TORQUE CONVERTER

5 1 2 3 4

73033TM00

1 Turbine 3 Pump 5 Input flange

2 Stator 4 Transmission pump

The converter is working according to the Trilok-system, i.e. it assumes at high turbine speed the
characteristics, and with it the favorable efficiency of a fluid clutch.
The converter is designed according to the engine power so that the most favorable operating
conditions are obtained for each installation case.
The Torque converter is composed of 3 main components :
Pump wheel - turbine wheel - stator (reaction member)
These 3 impeller wheels are arranged in such a ring-shape system that the fluid is streaming through
the circuit components in the indicated order.
Pressure oil from the transmission pump is constantly streaming through the converter. In this way, the
converter can fulfill its task to multiply the torque of the engine and at the same time, the heat created in
the converter is dissipated via the escaping oil.
The oil which is streaming out of the pump wheel, enters the turbine wheel and is there inversed in the
direction of flow.
According to the rate of reversion, the turbine wheel and with it also the output shaft is receiving a more
or less high reaction torque. The stator (reaction member), following the turbine, has the task to reverse
the oil streaming out of the turbine once more and to deliver it under the suitable discharge direction to
the pump wheel.
Due to the reversion, the stator receiving a reaction torque.
The relation turbine torque/pump torque is called torque multiplication. This is the higher, the greater
the speed difference of pump wheel and turbine wheel will be.
Therefore, the maximum torque multiplication is created at stationary turbine wheel.
With increasing output speed, the torque multiplication is decreasing. The adaption of the output speed
to a certain required output torque will be infinitely variable and automatically achieved by the torque
converter.

3-3
when the turbine speed is reaching about 80% of the pump speed, the torque multiplication becomes
1.0 i.e. the turbine torque becomes equal to that of the pump torque.
From this point on, the converter is working similar to a fluid clutch.
A stator freewheel serves to improve the efficiency in the upper driving range, in the torque
multiplication range it is backing-up the torque upon the housing, and is released in the clutch range.
In this way, the stator can rotate freely.

Function of a hydrodynamic torque converter (schematic view)

TP = Torque of the pump wheel

TT = Torque of the turbine wheel
TR = Torque of the reaction member (stator)
Pump wheel TR

Turbine wheel
From the engine
TT

TP

To the gearbox

Starting nT = 0
condition 1 1.5 Reaction member 2.5
(Stator) Machine standing
still

Intermediate
condition 1 <1.5 <2.5 nT < n engine

Condition in the
coupling point 1 0 1 nT = 0.8n engine

7577APT100

3-4
3. TRANSMISSION
1) LAYOUT

12

11

2
10
3

15
4

14
6

13 7

7407APT03

1 Reverse clutch (KR) 6 Rear output flange 11 Converter

2 Engine-dependent 7 Converter side output 12 Inductive transmitter
power take-off flange for engine speed
3 Forward clutch (KV) 8 Output shaft 13 4th clutch (K4)
4 2nd clutch (K2) 9 Transmission pump 14 Converter relief valve
5 3rd clutch (K3) 10 Input flange 15 1st clutch (K1)

3-5
 2) INSTALLATION VIEW

1 2 9 10 11 12 14

15

20

3
16
8 19

3 13 18

4 17

7 6 5

73093PT02

1 Lifting lugs 11 Breather

2 Input flange-input through universal shaft 12 Transmission-case cover
3 Transmission suspension threads M20 13 Transmission case
4 Output flange-converter side 14 Power take-off; Coaxial;
5 Oil drain plug with magnetic insert M38×1.5 Engine-dependent
6 Model identification plate 15 Electro-hydraulic control
7 Attachment possibility for oil level tube 16 Difference pressure switch for pressure filter
with oil dipstick (converter side) 17 Transmission suspension threads M20
8 Attachment possibility for emergency 18 Output flange-rear
steering pump 19 Exchange filter (fine filter)
9 Converter 20 Filter head with connection for filter
10 Converter bell housing restriction switch

3-6
 3) OPERATION OF TRANSMISSION
(1) Forward
① Forward 1st
In 1st forward, forward clutch and 1st clutch are engaged.
Forward clutch and 1st clutch are actuated by the hydraulic pressure applied to the clutch piston.

KR KR
KV IN

K4
K2

INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT04

3-7
 ② Forward 2nd
In 2nd forward, forward clutch and 2nd clutch are engaged.
Forward clutch and 2nd clutch are actuated by the hydraulic pressure applied to the clutch
piston.

KR KR
KV IN

K4
K2

INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT05

3-8
 ③ Forward 3rd
In 3rd forward, forward clutch and 3rd clutch are engaged.
Forward clutch and 3rd clutch are actuated by the hydraulic pressure applied to the clutch
piston.

KR KR
KV IN

K4
K2

INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT06

3-9
 ④ Forward 4th
In 4th forward, 4th clutch and 3rd clutch are engaged.
4th clutch and 3rd clutch are actuated by the hydraulic pressure applied to the clutch piston.

KR KR
KV IN

K4
K2
INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT07

3-10
 (2) Reverse
① Reverse 1st
In 1st reverse, reverse clutch and 1st clutch are engaged.
Reverse clutch and 1st clutch are actuated by the hydraulic pressure applied to the clutch piston.

KR KR
KV IN

K4
K2

INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT08

3-11
 ② Reverse 2nd
In 2nd reverse, reverse clutch and 2nd clutch are engaged.
Reverse clutch and 2nd clutch are actuated by the hydraulic pressure applied to the clutch
piston.

KR KR
KV IN

K4
K2

INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT09

3-12
 ③ Reverse 3rd
In 3rd reverse, reverse clutch and 3rd clutch are engaged.
Reverse clutch and 3rd clutch are actuated by the hydraulic pressure applied to the clutch piston.

KR KR
KV IN

K4
K2

INPUT

K3 K1

KV
OUT

GEAR PATTERN

K2

K1 K3

K4

OUTPUT OUTPUT

7607PT10

3-13
4) ELECTRO-HYDRAULIC SHIFT CONTROL WITH PROPORTIONAL VALVE

2 1 3

A A
Y6 Y1

Y5 Y2

B
Y4 Y3

3 6

2 6 1 4 11 9 10

Y5

SECTION A-A SECTION B-B

8 7
73033CV01

1 Pressure reducing valve (9bar) 7 Intermediate sheet

2 System pressure valve (16+2bar) 8 Duct plate
3 Housing 9 Oscillation damper
4 Cable harness 10 Follow-on slide
5 Cover 11 Pressure regulator
6 Valve block

Transmission control, see schedule of hydraulic circuit, electro-hydraulic control unit and measuring
points at page 3-2, 3-14 and 3-67.
The six clutches of the transmission are selected via the 6 proportional valves P1 to P6. The
proportional valve (pressure regulator unit) is composed of pressure regulator (e.g. Y1), follow-on
slide and vibration damper.
The control pressure of 9 bar for the actuation of the follow-on slides is created by the pressure
reducing valve. The pressure oil (16+2bar) is directed via the follow-on slide to the respective
clutch.

3-14
 Due to the direct proportional selection with separated pressure modulation for each clutch, the
pressures to the clutches, which are engaged in the gear change, will be controlled. In this way, a
hydraulic intersection of the clutches to be engaged and disengaged becomes possible.
This is creating spontaneous shiftings without traction force interruption.
At the shifting, the following criteria are considered:
- Speed of engine, turbine, central gear train and output.
- Transmission temperature.
- Shifting mode (up-, down-, reverse shifting and speed engagement out of neutral).
- Load condition (full and part load, traction, overrun inclusive consideration of load cycles during
the shifting).
The main pressure valve is limiting the maximum control pressure to 16+2 bar and releases the
main stream to the converter and lubricating circuit.
In the inlet to the converter, a converter satety valve is installed which protects the converter from
high internal pressures (opening pressure 11bar).
Within the converter, the oil serves to transmit the power according to the well-known
hydrodynamic principle (see torque converter, page 3-3).
To avoid cavitation, the converter must be always completely filled with oil.
This is achieved by a converter back pressure back-up valve, rear-mounted to the converter, with
an opening pressure of at least 4.3bar.
The oil, escaping out of the converter, is directed to a oil cooler.
The oil is directed from the oil cooler to the transmission and from there to the lubricating oil circuit,
so that all lubricating points are supplied with cooled oil.
In the electro-hydraulic control unit are 6 pressure regulators installed.

5) GEAR SELECTOR (DW-3)

The gear selector is designed for the
mounting on the left side of the steering
column. The positions (speeds) 1 to 4 are F
1

selected by a rotary motion, the driving 4

2
3
N

R
direction Forward (F)-Neutral (N)-Reverse
(R) by tilting the gear selector lever.
The gear selector is also available with
integrated kickdown push button.
For the protection from unintended start off,
a neutral interlock is installed.
N D
Position N - Gear selector lever blocked in
this position.
Position D - Driving. 73033TM17

3-15
6) ELECTRIC CONTROL UNIT
(1) Complete system

1
2

14
5 12
4 15
3

10
9
7

11

2
6

13 8

7309S3PT33

1 Transmission control unit(EST-37A)

2 Kickdown switch
3 Clutch cut off mode switch
4 Transmission shift mode switch
5 Monitor
6 Gear selector(DW-3) with integrated kickdown switch
7 Power supply connection
8 Transmission
9 Cable to inductive transmitter - speed central gear train
10 Cable to inductive transmitter - speed turbine
11 Cable to inductive transmitter - speed engine
12 Cable to speed sensor output and speedometer
13 Cable to plug connection on the electro - hydraulic control unit
14 CAN-Connection
15 Wiring
(2) Description of the basic functions
The powershift transmissions is equipped is electronic transmission control unit(EST-37A), devel-
oped for it.
The system is processing the desire of the driver according to the following criteria.
·Gear determination depending on controller position, driving speed and load condition.

3-16
 ·Protection from operating errors as far as necessary, is possible via electronic protection
(programming).
·Protection from over-speeds(On the basis of engine and turbine speed).
·Automatic reversing(Driving speed-dependent).
·Pressure cut-off possible(Disconnecting of the drive train for maximum power on the power
take-off).
·Change-over possibility for Auto-/Manual mode.
·Kick down functions possible.
(3) Driving and shifting
(3
- Neutral position :
Neutral position will be selected via the controller.
After the ignition is switched on, the electronics remains in the waiting state. By the position
NEUTRAL of the controller, resp. by pressing the pushbutton NEUTRAL, the EST-37A becomes
ready for operation.
Now, a gear can be engaged.
- Starting :
The starting of the engine has always to be carried out in the NEUTRAL POSITION of the
controller.
For safety reasons it is to recommend to brake the machine securely in position with the parking
brake prior to start the engine.
After the starting of the engine and the preselection of the driving direction and the gear, the
machine can be set in motion by acceleration.
At the start off, the converter takes over the function of a master clutch.
On a level road it is possible to start off also in higher gears.
- Upshifting under load
Upshifting under load will be then realized if the machine can still accelerate by it.
- Downshifting under load
Downshifting under load will be realized if more traction force is needed.
- Upshifting in overrunning condition
In the overrunning mode, the upshifting will be suppressed by accelerator pedal idling position, if
the speed of the machine on a downgrade should not be further increased.
- Downshifting in overrunning condition
Downshiftings in overrunning mode will be then carried out if the machine should be retarded.
If the machine will be stopped and is standing with running engine and engaged transmission,
the engine cannot be stalled. On a level and horizontal roadway it is possible that the machine
begins to crawl, because the engine is creating at idling speed a slight drag torque via the con-
verter.
It is convenient to brake the machine at every stop securely in position with the parking brake.
At longer stops, the controller has to be shifted to the NEUTRAL POSITION.
At the start off, the parking brake has to be released. We know from experience that at a con-
verter transmission it might not immediately be noted to have forgotten this quite normal operat-
ing step because a converter, due to its high ratio, can easily overcome the braking torque of the
parking brake.

3-17
 Temperature increases in the converter oil as well as overheated brakes will be the consequences
to be find out later.
Neutral position of the selector switch at higher machine speeds (above stepping speed) is not
admissible.
Either a suitable gear is to be shifted immediately, or the machine must be stopped at once.
(4) Independent calibration of the shifting elements (AEB)
(4
The AEB has the task to compensate tolerances (plate clearance and pressure level) which are
influencing the filling procedure of the clutches. For each clutch, the correct filling parameters are
determined in one test cycle for :
·Period of the quick-filling time
·Level of the filling compensating pressure
The filling parameters are stored, together with the AEB-program and the driving program in the
transmission electronics. Because the electronics will be separately supplied, the AEB-cycle must
be started only after the installation of both components in the machine, thus ensuring the correct
mating(Transmission and electronics).
※ It is imperative, to respect the following test conditions :
- Shifting position neutral
- Engine in idling speed
- Parking brake actuated
- Transmission in operating temperature
※ After a replacement of the transmission, the electrohydraulic control or the TCU in the machine,
the AEB-cycle must be as well carried out again.
The AEB-cylcle continues for about 3 to 4 minutes. The determined filling parameters are stored
in the EEProm of the electronics. In this way, the error message F6 shown on the display will be
cancelled also at non-performed AEB.
(5) Pressure cut-off
(5
In order to provide the full engine power for the hydraulic system, the control can be enlarged for
the function of a pressure cut-off in the 1st and 2nd speed. In this way, the pressure in the power-
shift clutches will be cut-off, and the torque transmission in the drive train will be eliminated by it.
This function will be released at the actuation of a switch, arranged on the brake pedal.
For a soft restart, the pressure will be build-up via a freely programmable characteristic line.

3-18
4. FAULT CODE
1) MACHINE FAULT CODE
HCESPN FMI Description
Hydraulic oil temperature sensor circuit - Voltage above normal, or shorted to high source (or
3
101 open circuit)
4 Hydraulic oil temperature sensor circuit - Voltage below normal, or shorted to low source
5 Engine cooling fan EPPR valve circuit - Current below normal, or open circuit
145
6 Engine cooling fan EPPR valve bircuit - Current above normal
Boom up lever detent solenoid circuit - Voltage below normal, or shorted to low source (or
4
172 open circuit)
6 Boom up lever detent solenoid circuit - Current above normal
Boom down lever detent solenoid circuit - Voltage below normal, or shorted to low source (or
4
173 open circuit)
6 Boom down lever detent solenoid circuit - Current above normal
Bucket lever detent solenoid circuit - Voltage below normal, or shorted to low source (or open
4
174 circuit)
6 Bucket lever detent solenoid circuit - Current above normal
Engine cooling fan reverse solenoid circuit - Voltage below normal, or shorted to low source (or
4
181 open circuit)
6 Engine cooling fan reverse solenoid circuit - Current above normal
Engine cooling fan reverse driving status signal circuit - Voltage below normal, or shorted to
4
183 low source (or open circuit)
6 Engine cooling fan reverse driving status signal circuit - Current above normal
Emergency steering pump relay circuit - Voltage below normal, or shorted to low source (or
4
187 open circuit)
6 Emergency steering pump relay circuit – Current above normal
0 Steering main pump pressure sensor data above normal range (or open circuit)
1 Steering main pump pressure sensor data below normal range
202
2 Steering main pump pressure sensor data error
4 Steering main pump pressure sensor circuit - Voltage below normal, or shorted to low source
0 Emergency steering pump pressure sensor data above normal range (or open circuit)
1 Emergency steering pump pressure sensor data below normal range
203 2 Emergency steering pump pressure sensor data error
Emergency steering pump pressure sensor circuit - Voltage below normal, or shorted to low
4
source
0 Boom cylinder pressure sensor data above normal range (or open circuit)
1 Boom cylinder pressure sensor data below normal range
204
2 Boom cylinder pressure sensor data error
4 Boom cylinder pressure sensor circuit - Voltage below normal, or shorted to low source
0 Bucket cylinder pressure sensor data above normal range (or open circuit)
1 Bucket cylinder pressure sensor data below normal tange
205
2 Bucket cylinder pressure sensor data error
4 Bucket cylinder pressure sensor circuit - Voltage below normal, or shorted to low source

3-19
HCESPN FMI Description
3 Fuel level sensor circuit - Voltage above normal, or shorted to high source (or open circuit)
301
4 Fuel level sensor circuit - Voltage below normal, or shorted to low source
Engine coolant temperature sensor circuit - Voltage above normal, or shorted to high source
3
304 (or open circuit)
4 Engine coolant temperature sensor circuit - Voltage below normal, or shorted to low source
310 8 Engine speed signal error – Abnormal frequency or pulse width
318 8 Engine cooling fan speed signal error – Abnormal frequency or pulse width
4 Engine preheat relay circuit – Voltage below normal, or shorted to low source (or open circuit)
322
6 Engine preheat relay circuit - Current above normal
4 Fuel warmer relay circuit - Voltage below normal, or shorted to low source (or open circuit)
325
6 Fuel warmer relay circuit – Current above normal
4 Anti-restart relay circuit - Voltage below normal, or shorted to low source (or open circuit)
327
6 Anti-restart relay circuit – Current above normal
Engine power mode selector circuit – Voltage above normal, or shorted to high source (or
3
346 open circuit)
4 Engine power mode selector circuit – Voltage below normal, or shorted to low source
0 Brake oil pressure sensor data above normal range (or open circuit)
1 Brake oil pressure sensor data below normal range
503
2 Brake oil pressure sensor data error
4 Brake oil pressure sensor circuit – Voltage below normal, or shorted to Low Source
0 Parking oil pressure sensor data above normal range (or open circuit)
1 Parking oil pressure sensor data below normal range
507
2 Parking oil pressure sensor data error
4 Parking oil pressure sensor circuit - Voltage below normal, or shorted to low source
Clutch cut off mode selector circuit – Voltage above normal, or shorted to high source (or
3
551 open circuit)
4 Clutch cut off mode selector circuit – Voltage below normal, or shorted to low source
Transmission shift mode selector circuit – Voltage above normal, or shorted to high source (or
3
552 open circuit)
4 Transmission shift mode selector circuit – Voltage below normal, or shorted to low source
0 Differential lock pressure sensor data above normal range (or open circuit)
1 Differential lock pressure sensor data below normal range
558
2 Differential lock pressure sensor data error
4 Differential lock pressure sensor circuit - Voltage below normal, or shorted to low source
701 4 Hourmeter circuit - Voltage below normal, or shorted to low source
0 Battery voltage high
705
1 Battery voltage low

3-20
HCESPN FMI Description
707 1 Alternator node I voltage low (or open circuit)
3 Buzzer circuit - Voltage above normal, or shorted to high source
723
4 Buzzer circuit - Voltage below normal, or shorted to low source (or open circuit)
4 Wiper relay circuit - Voltage below normal, or shorted to low source (or open circuit)
727
6 Wiper relay circuit – Current above normal
Boom position sensor signal circuit – Voltage above normal, or shorted to high
3
728 source (or open circuit)
4 Boom position sensor signal circuit – Voltage below normal, or shorted to low source
Bucket position sensor signal circuit – Voltage above normal, or shorted to high
3
source (or open circuit)
729
Bucket position sensor signal circuit – Voltage below normal, or shorted to low
4
source
730 19 APTC heater PWM output duty operation error
830 12 MCU internal memory error
840 2 Cluster communication error
841 2 ECM communication error
842 2 TCU communication error
843 2 APTC communication error
844 2 Monitor communication error
850 2 RCM communication error

3-21
2) ENGINE FAULT CODES
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Engine control module critical internal failure - Possible no noticeable performance effects,
111
Bad intelligent device or component. Error engine dying, or hard starting.
629
internal to the ECM related to memory hardware
12
failures or internal ECM voltage supply circuits.
Engine magnetic crankshaft speed/position lost Fueling to injectors is disabled and the engine
115 both of two signals - Data erratic, intermittent, or can not be started.
612 incorrect. The ECM has detected that the
2 primary engine speed sensor and the backup
engine speed sensor signals are reversed.
Intake manifold 1 pressure sensor circuit - Engine power derate.
122 Voltage above normal, or shorted to high source.
102 High signal voltage detected at the intake
3 manifold pressure circuit.
Intake manifold 1 pressure sensor circuit - Engine power derate.
123 Voltage below normal, or shorted to low Source.
102 Low signal voltage or open circuit detected at the
4 intake manifold pressure circuit.
Intake manifold 1 pressure - Data valid but above Engine power derate.
124 normal operational range - Moderately severe
102 level. Intake manifold pressure has exceeded the
16 maximum limit for the given engine rating.
Accelerator pedal or lever position sensor 1 Severe derate in power output of the engine.
131 circuit - Voltage above normal, or shorted to high Limp home power only.
91 source. High voltage detected at accelerator
3 pedal position circuit.
Accelerator pedal or lever position sensor 1 Severe derate in power output of the engine.
132 circuit - Voltage below normal, or shorted to low Limp home power only.
91 source. Low voltage detected at accelerator
4 pedal position signal circuit.
Remote accelerator pedal or lever position Remote accelerator will not operate. Remote
133 sensor 1 circuit - Voltage above normal, or accelerator position will be set to zero percent.
974 shorted to high source. High voltage detected at
3 remote accelerator pedal position circuit.
Remote accelerator pedal or lever position Remote accelerator will not operate. Remote
134 sensor 1 circuit - Voltage below normal, or accelerator position will be set to zero percent.
974 shorted to low source. Low voltage detected at
4 remote accelerator pedal position signal circuit.
Engine oil rifle pressure 1 sensor circuit - Voltage None on performance. No engine protection
135 above normal, or shorted to high source. High for oil pressure.
100 signal voltage detected at the engine oil pressure
3 circuit.
Engine oil rifle pressure 1 sensor circuit - Voltage None on performance. No engine protection
141 below normal, or shorted to low source. Low for oil pressure.
100 signal voltage detected at engine oil pressure
4 circuit.
143 Engine oil rifle pressure - Data valid but below None on performance.
100 normal operational range - Moderately severe
18 level.
Engine coolant temperature 1 sensor circuit - Possible white smoke. Fan will stay ON if
144
Voltage above normal, or shorted to high source. controlled by ECM. No engine protection for
110
High signal voltage or open circuit detected at engine coolant temperature.
3
engine coolant temperature circuit.

3-22
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Engine Coolant Temperature 1 Sensor Circuit - Possible white smoke. Fan will stay ON if
145
Voltage Below Normal, or Shorted to Low controlled by ECM. No engine protection for
110
Source. Low signal voltage detected at engine engine coolant temperature.
4
coolant temperature circuit.
Engine Coolant Temperature - Data Valid but Progressive power derate increasing in
146 Above Normal Operational Range - Moderately severity from time of alert.
110 Severe Level. Engine coolant temperature signal
16 indicates engine coolant temperature is above
engine protection warning limit.
Accelerator Pedal or Lever Position 1 Sensor Severe derate in power output of the engine.
Circuit Frequency - Data Valid but Below Normal Limp home power only.
147
Operational Range - Most Severe Level. A
91
frequency of less than 100 Hz has been
1
detected at the frequency throttle input to the
ECM.
Accelerator Pedal or Lever Position Sensor 1 - Severe derate in power output of the engine.
148 Data Valid but Above Normal Operational Limp home power only.
91 Range - Most Severe Level. A frequency of
0 more than 1500 Hz has been detected at the
frequency throttle input to the ECM.
Engine Coolant Temperature - Data Valid but Progressive power derate increasing in
151 Above Normal Operational Range - Most severity from time of alert. If Engine Protection
110 Severe Level. Engine coolant temperature signal Shutdown feature is enabled, engine will shut
0 indicates engine coolant temperature above down 30 seconds after Red Stop Lamp starts
engine protection critical limit. flashing.
Intake Manifold 1 Temperature Sensor Circuit - Possible white smoke. Fan will stay ON if
153 Voltage Above Normal, or Shorted to High controlled by ECM. No engine protection for
105 Source. High signal voltage detected at intake intake manifold air temperature.
3 manifold air temperature circuit.
Intake Manifold 1 Temperature Sensor Circuit - Possible white smoke. Fan will stay ON if
154 Voltage Below Normal, or Shorted to Low controlled by ECM. No engine protection for
105 Source. Low signal voltage detected at intake intake manifold air temperature.
4 manifold air temperature circuit.
Intake Manifold 1 Temperature - Data Valid but Progressive power derate increasing in
155 Above Normal Operational Range - Most severity from time of alert. If Engine Protection
105 Severe Level. Intake manifold air temperature Shutdown feature is enabled, engine will shut
0 signal indicates intake manifold air temperature down 30 seconds after Red Stop Lamp starts
above engine protection critical limit. flashing.
187 Sensor Supply 2 Circuit - Voltage Below Normal, Engine power derate.
520195 or Shorted to Low Source. Low voltage detected
4 at the sensor supply number 2 circuit.
195 Coolant Level Sensor 1 Circuit - Voltage Above None on performance.
111 Normal, or Shorted to High Source. High signal
3 voltage detected at engine coolant level circuit.
196 Coolant Level Sensor 1 Circuit - Voltage Below None on performance.
111 Normal, or Shorted to Low Source. Low signal
4 voltage detected at engine coolant level circuit.
197 Coolant Level - Data Valid but Below Normal None on performance.
111 Operational Range - Moderately Severe Level.
18 Low coolant level has been detected.
Barometric Pressure Sensor Circuit - Voltage Engine power derate.
221
Above Normal, or Shorted to High Source. High
108
signal voltage detected at barometric pressure
3
circuit.

3-23
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Barometric Pressure Sensor Circuit - Voltage Engine power derate.
222
Below Normal, or Shorted to Low Source. Low
108
signal voltage detected at barometric pressure
4
circuit.
227 Sensor Supply 2 Circuit - Voltage Above Normal, Engine power derate.
520195 or Shorted to High Source. High voltage
3 detected at sensor supply number 2 circuit.
Engine Crankshaft Speed/Position - Data Valid Fuel injection disabled until engine speed falls
234
but Above Normal Operational Range - Most below the overspeed limit.
190
Severe Level. Engine speed signal indicates
0
engine speed above engine protection limit.
Coolant Level - Data Valid but Below Normal Progressive power derate increasing in
235 Operational Range - Most Severe Level. Low severity from time of alert. If Engine Protection
111 engine coolant level detected. Shutdown feature is enabled, engine will shut
1 down 30 seconds after Red Stop Lamp starts
flashing.
237 External Speed Command Input (Multiple Unit
644 Synchronization) - Data Erratic, Intermittent, or
2 Incorrect. Communication between multiple
engines may be intermittent.
238 Sensor Supply 3 Circuit - Voltage Below Normal, Possible hard starting and rough running.
520196 or Shorted to Low Source. Low voltage detected
4 on the +5 volt sensor supply circuit to the engine
speed sensor.
241 Wheel-based vehicle speed - Data erratic, Engine speed limited to ,maximum engine
84 intermittent, or incorrect. The ECM lost the speed without VSS parameter value. Cruise
2 vehicle speed signal. control, gear-down protection, and road speed
governor will not work.
242 Wheel-based vehicle speed sensor circuit Engine speed limited to maximum engine
84 tampering has been detected - Abnormal rate of speed without VSS parameter value. Cruise
10 change. Signal indicates an intermittent control, gear-down protection, and road speed
connection or VSS tampering. governor will not work.
245 Fan control circuit - Voltage below normal, or The fan may stay on continuously or not run at
647 shorted to low source. Low signal voltage all.
4 detected at the fan control circuit when
commanded on.
271 Fuel pump pressurizing assembly 1 circuit - Engine will run poorly at idle. Engine will have
1347 Voltage below normal, or shorted to low source. low power. Fuel pressure will be higher than
4 Low signal voltage detected at the fuel pump commanded.
actuator circuit.
Fuel pump pressurizing assembly 1 circuit - Engine will not run or engine will run poorly.
272
Voltage above normal, or shorted to high source.
1347
High signal voltage or open circuit detected at
3
the fuel pump actuator circuit.
281 Fuel pump pressur izing assembly 1 - Engine will not run or possible low power.
1347 Mechanical system not responding properly or
7 out of adjustment.
SAE J1939 multiplexing PGN timeout error - At least one multiplexed device will not
285
Abnormal update rate. The ECM expected operate properly.
639
information from a multiplexed device but did not
9
receive it soon enough or did not receive it at all.
SAE J1939 multiplexing configuration error - At least one multiplexed device will not
286
Out of calibration. The ECM expected operate properly.
639
information from a multiplexed device but only
13
received a portion of the necessary information.

3-24
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
SAE J1939 multiplexed accelerator pedal or Engine may only idle or engine will not
287 lever sensor system - received network data In accelerate to full speed.
91 error. The OEM vehicle electronic control unit
19 (VECM) detected a fault with its accelerator
pedal.
SAE J1939 Multiplexing Remote Accelerator The engine will not respond to the remote
288 Pedal or Lever Position Sensor Circuit - throttle. Engine may only idle. The primary or
974 Received Network Data In Error. The OEM cab accelerator may be able to be used.
19 vehicle electronic control unit (VECM) detected
a fault with the remote accelerator.
292 Auxiliary temperature Sensor Input 1 - Special Possible engine power derate.
441 instructions.
14
Auxiliary temperature sensor input 1 circuit - None on performance.
293 Voltage above normal, or shorted to high
441 source. High signal voltage or open circuit
3 detected at the OEM auxiliary temperature
circuit.
Auxiliary temperature sensor input 1 circuit - None on performance.
294 Voltage below normal, or shorted to low source.
441 Low signal voltage detected at the OEM
4 auxiliary temperature circuit.
296 Auxiliary pressure sensor input 1 - Special Possible engine power derate.
1388 instructions.
14
Auxiliary pressure sensor input 1 circuit - None on performance.
297
Voltage above normal, or shorted to high
1388
source. High signal voltage detected at the OEM
3
pressure circuit.
Auxiliary pressure sensor input 1 circuit - None on performance.
298 Voltage below normal, or shorted to low source.
1388 Low signal voltage or open circuit detected at
4 the OEM pressure circuit.
319 Real time clock power interrupt - Data erratic, None on performance. Data in the ECM will
251 intermittent, or incorrect. Real time clock lost not have accurate time and date information.
2 power.
Injector solenoid driver cylinder 1 circuit - Engine can possibly misfire or run rough.
Current below normal, or open circuit. High
322 resistance detected on injector number 1 circuit
651 or no current detected at number 1 injector
5 driver or return pin when the voltage supply at
the harness is on.
Injector solenoid driver cylinder 5 circuit - Engine can possibly misfire or run rough.
Current below normal, or open circuit. High
323 resistance detected on injector number 5 circuit
655 or no current detected at number 5 injector
5 driver or return pin when the voltage supply at
the harness is on.
Injector solenoid driver cylinder 3 circuit - Engine can possibly misfire or run rough.
Current below normal, or open circuit. High
324 resistance detected on injector number 3 circuit
653 or no current detected at number 3 injector
5 driver or return pin when the voltage supply at
the harness is on.
Injector solenoid driver cylinder 6 circuit - Engine can possibly misfire or run rough.
Current below normal, or open circuit. High
325 resistance detected on injector number 6 circuit
656 or no current detected at number 6 injector
5 driver or return pin when the voltage supply at
the harness is on.

3-25
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Injector solenoid driver cylinder 2 circuit - Engine can possibly misfire or run rough.
Current below normal, or open circuit. High
331
resistance detected on injector number 2 circuit
652
or no current detected at number 2 injector
5
driver or return pin when the voltage supply at
the harness is on.
Injector solenoid driver cylinder 4 circuit - Engine can possibly misfire or run rough.
Current below normal, or open circuit. High
332
resistance detected on injector number 4 circuit
654
or no current detected at number 4 injector
5
driver or return pin when the voltage supply at
the harness is on.
Engine coolant temperature - Data erratic, The ECM will estimate engine coolant
334
intermittent, or incorrect. The engine coolant temperature.
110
temperature reading is not changing with engine
2
operating conditions.
342 Electronic calibration code incompatibility - Out Possible no noticeable performance effects,
630 of calibration. An incompatible calibration has engine dying, or hard starting.
13 been detected in the ECM.
343 Engine control module warning internal No performance effects or possible severe
620 hardware failure - Bad intelligent device or power derate.
12 component. Internal ECM failure.
351 Injector power supply - Bad intelligent device or Possible smoke, low power, engine misfire,
627 component. The ECM measured injector boost and/or engine will not start.
12 voltage is low.
352 Sensor supply 1 circuit - Voltage below normal, Engine power derate.
1079 or shorted to low source. Low voltage detected
4 at sensor supply number 1 circuit.
386 Sensor supply 1 circuit - Voltage above normal, Engine power derate.
1079 or shorted to high source. High voltage detected
3 at sensor supply number 1 circuit.
Engine oil rifle pressure - Data valid but below Progressive power derate increasing in
415 normal operational range - Most severe level. Oil severity from time of alert. If engine protection
100 pressure signal indicates oil pressure below the shutdown feature is enabled, engine will shut
1 engine protection critical limit. down 30 seconds after red stop lamp starts
flashing.
418 Water in fuel indicator - Data valid but above Possible white smoke, loss of power, or hard
97 normal operational range - Least severe level. starting.
15 water has been detected in the fuel filter.
428 Water in fuel indicator sensor circuit - Voltage None on performance. No water in fuel
97 above normal, or shorted to high source. High warning available.
3 voltage detected at the water in fuel circuit.
429 Water in fuel indicator sensor circuit - Voltage None on performance. No water in fuel
97 below normal, or shorted to low source. Low warning available.
4 voltage detected at the water in fuel circuit.
Accelerator pedal or lever idle validation switch - Engine will only idle.
431 Data erratic, intermittent, or incorrect. Voltage
558 detected simultaneously on both idle validation
2 and off-idle validation switches.
Accelerator pedal or lever idle validation circuit - Engine will only idle.
432 Out of calibration. Voltage at idle validation
558 on-idle and off-idle circuit does not match
13 accelerator pedal position.

3-26
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Engine oil rifle pressure - Data erratic, None on performance. No engine protection
435
intermittent, or incorrect. An error in the engine for oil pressure.
100
oil pressure switch signal was detected by the
2
ECM.
Battery 1 voltage - Data valid but below normal Engine may stop running or be difficult to start.
441
operational range - Moderately severe level.
168
ECM supply voltage is below the minimum
18
system voltage level.
Battery 1 Voltage - Data valid but above normal Possible electrical damage to all electrical
442
operational range - Moderately severe level. components.
168
ECM supply voltage is above the maximum
16
system voltage level.
449 Injector metering rail 1 pressure - Data valid but None or possible engine noise associated with
157 above normal operational range - Most severe higher injection pressures (especially at idle or
0 level. light load). Engine power is reduced.
Injector metering rail 1 pressure sensor circuit - Power and or speed derate.
451
Voltage above normal, or shorted to high source.
157
High signal voltage detected at the rail fuel
3
pressure sensor circuit.
Injector metering rail 1 pressure sensor circuit - Power and or speed derate.
452
Voltage below normal, or shorted to low source.
157
Low signal voltage detected at the rail fuel
4
pressure sensor circuit.
Intake manifold 1 temperature - Data valid but Progressive power derate increasing in
488 above normal operational range - Moderately severity from time of alert.
157 severe level. Intake manifold air temperature
16 signal indicates intake manifold air temperature
is above the engine protection warning limit.
497 Multiple unit synchronization switch - Data
1377 erratic, intermittent, or incorrect.
2
523 Auxiliary intermediate (PTO) speed switch None on performance.
611 validation - Data erratic, intermittent, or
2 incorrect.
Auxiliary input/output 2 circuit - Voltage above None on performance.
527 normal, or shorted to high source. High signal
702 voltage or open circuit has been detected at the
3 auxiliary input/output 2 circuit.
528 Auxiliary alternate torque validation switch - None on performance.
93 Data erratic, intermittent, or incorrect.
2
Auxiliary input/output 3 circuit - Voltage above
529
normal, or shorted to high source. Low signal
703
voltage has been detected at the auxiliary input/
3
output 2 circuit.
Injector metering rail 1 pressure - Data valid but The ECM will estimate fuel pressure and
553 above normal operational range - Moderately power is reduced.
157 severe level. The ECM has detected that fuel
16 pressure is higher than commanded pressure.
Injector metering rail 1 pressure - Data erratic, Possibly hard to start, low power, or engine
554 Intermittent, or incorrect. The ECM has smoke.
157 detected that the fuel pressure signal is not
2 changing.

3-27
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Injector metering rail 1 pressure - Data Valid Either the engine will not start or the engine
559 but Below Normal Operational Range - will not have starter lockout protection.
157 Moderately Severe Level. The ECM has
18 detected that fuel pressure is lower than
commanded pressure.
Starter relay driver circuit - Voltage above The engine will not have starter lockout
584
normal, or shorted to high source. Open circuit protection.
677
or high voltage detected at starter lockout
3
circuit.
585 Starter relay driver circuit - Voltage below Engine power derate. The ECM uses an
677 normal, or shorted to low source. Low voltage estimated turbocharger speed.
4 detected at starter lockout circuit.
Turbocharger 1 speed - Data valid but above Amber lamp will light until high battery voltage
595
normal operational range - Moderately severe condition is corrected.
103
level. High turbocharger speed has been
16
detected.
599 Auxiliary commanded dual output shutdown - None or possible engine noise associated with
640 Special instructions. higher injection pressures (especially at idle or
14 light load). Engine power is reduced.
Turbocharger 1 speed - Data valid but below Engine can run rough. Possibly poor starting
687
normal operational range - Moderately severe capability. Engine runs using backup speed
103
level. Low turbocharger speed detected by the sensor. Engine power is reduced.
18
ECM.
689 Engine crankshaft speed/position - Data Engine power derate.
190 erratic, intermittent, or incorrect. Loss of signal
2 from crankshaft sensor.
Turbocharger 1 compressor inlet temperature Engine power derate.
691 circuit - Voltage above normal, or shorted to
1172 high source. High signal voltage detected at
3 turbocharger compressor inlet air temperature
circuit.
Turbocharger 1 compressor inlet temperature Engine will run derated. Excessive black
692
circuit - Voltage below normal, or shorted to low smoke, hard start, and rough idle possible.
1172
source. Low signal voltage detected at
4
turbocharger compressor inlet air tempera
Engine speed / position camshaft and Possible no noticeable performance effects,
crankshaft misalignment - Mechanical system engine dying, or hard starting.
731
not responding properly or out of adjustment.
723
mechanical misalignment between the
7
crankshaft and camshaft engine speed
sensors.
757 Electronic control module data lost - Condition Possible poor starting. Engine power derate.
611 exists. Severe loss of data from the ECM.
31
Engine camshaft speed / position sensor - Possible engine power derate.
778
Data erratic, intermittent, or incorrect. The ECM
723
has detected an error in the camshaft position
2
sensor signal.
Auxiliary equipment sensor input 3 - Root Possible no noticeable performance effects or
779 cause not known. e n g i n e d y i n g o r h a r d s t a r t i n g . Fa u l t
703 information, trip information, and maintenance
11 monitor data may be inaccurate.

3-28
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
Power supply lost with ignition on - Data erratic, Engine will shut down.
intermittent, or incorrect. Supply voltage to the
1117 ECM fell below 6.2 volts momentarily, or the
627 ECM was not allowed to power down correctly
2 (retain battery voltage for 30 seconds after key
OFF).
1633 OEM datalink cannot transmit - Data erratic, Engine will only idle.
625 intermittent, or incorrect. Communications
2 within the OEM datalink network is intermittent.
Sensor supply 4 circuit - Voltage above normal, Engine will only idle.
2185 or shor ted to high source. High voltage
520197 detected at +5 volt sensor supply circuit to the
3 accelerator pedal position sensor.
Sensor supply 4 circuit - Voltage below normal, Possibly hard to start, low power, or engine
2186 or shorted to low source. Low voltage detected smoke.
520197 at +5 volt sensor supply circuit to the
4 accelerator pedal position sensor.
Injector metering rail 1 pressure - Data valid but Engine may be difficult to start.
2249 below normal operational range - Most severe
157 level. The ECM has detected that fuel pressure
1 is lower than commanded pressure.
Electric lift pump for engine fuel supply circuit - Engine may be difficult to start.
2265 Voltage above normal, or shorted to high
1075 source. High voltage or open detected at the
3 fuel lift pump signal circuit.
Electric lift pump for engine fuel supply circuit - Possible low power.
2266 Voltage below normal, or shorted to low source.
1075 Low signal voltage detected at the fuel lift pump
4 circuit.
Electronic fuel injection control valve circuit -Engine may exhibit misfire as control switches
2311 Condition exists. Fuel pump actuator circuit from the primary to the backup speed sensor.
633 resistance too high or too low. Engine power is reduced while the engine
31 operates on the backup speed sensor.
2321 Engine crankshaft speed/position - Data erratic, Possible low power.
190 intermittent, or incorrect. crankshaft engine
2 speed sensor intermittent synchronization.
Engine camshaft speed / position sensor - Data Engine power derate.
2322
erratic, intermittent, or incorrect. Camshaft
723
engine speed sensor intermittent
2
synchronization.
2345 Turbocharger 1 Speed - Abnormal rate of Engine power derate.
103 change. The turbocharger speed sensor has
10 detected an erroneous speed value.
Turbocharger turbine inlet temperature Engine power derate.
2346 (Calculated) - Data valid but above normal
2789 operational range - Least severe level.
15 Turbocharger turbine inlet temperature has
exceeded the engine protection limit.
2347 Turbocharger compressor outlet temperature Engine brake on cylinders 1, 2, and 3 can not
2790 (Calculated) - Data valid but above normal be activated or exhaust brake will not operate.
15 operational range - Least severe level.
2377 Fan control circuit - Voltage above normal, or Variable geometry turbocharger will go to the
647 shorted to high source. Open circuit or high open position.
3 voltage detected at the fan control circuit.

3-29
Fault code
J1939 SPN Reason Effect (only when fault code is active)
J1939 FMI
2384 VGT actuator driver circuit - Voltage below Variable geometry turbocharger may be in
641 normal, or shorted to low source. Low voltage either the open or closed position.
4 detected at turbocharger control valve circuit.
VGT actuator driver circuit - Voltage above The intake air heaters may be ON or OFF all
2385
normal, or shorted to high source. Open circuit the time.
641
or high voltage detected at turbocharger
3
control valve circuit.
2555 Intake air heater 1 circuit - Voltage above The intake air heaters may be ON or OFF all
729 normal, or shorted to high source. High voltage the time.
3 detected at the intake air heater signal circuit.
2556 Intake air heater 1 circuit - Voltage below Can not control transmission.
729 normal, or shorted to low source. Low voltage
4 detected at the intake air heater signal circuit.
2557 Auxiliary PWM driver 1 circuit - Voltage above Can not control transmission.
697 normal, or shorted to high source. High signal
3 voltage detected at the analog torque circuit.
2558 Auxiliary PWM driver 1 circuit - Voltage below Power derate and possible engine shutdown if
697 normal, or shorted to low source. Low signal engine protection shutdown feature is enabled.
4 voltage detected at the analog torque circuit.
Intake manifold 1 pressure - Data erratic,
2973 intermittent, or incorrect. The ECM has
102 detected an intake manifold pressure signal
2 that is too high or low for current engine
operating conditions.

3-30
3) DEFINITION OF OPERATING MODES
(1) Normal
There's no failure detected in the transmission system or the failure has no or slight effects on
transmission control. TCU will work without or in special cases with little limitations. (See
following table)
(2) Substitute clutch control
TCU can't change the gears or the direction under the control of the normal clutch modulation.
TCU uses the substitute strategy for clutch control. All modulations are only time controlled.
(Comparable with EST 25)
(3) Limp-home
The detected failure in the system has strong limitations to transmission control. TCU can
engage only one gear in each direction. In some cases only one direction will be possible.
TCU will shift the transmission into neutral at the first occurrence of the failure. First, the operator
must shift the gear selector into neutral position.
If output speed is less than a threshold for neutral to gear and the operator shifts the gear selector
into forward or reverse, the TCU will select the limp-home gear.
If output speed is less than a threshold for reversal speed and TCU has changed into the limp-
home gear and the operator selects a shuttle shift, TCU will shift immediately into the limp-home
gear of the selected direction.
If output speed is greater than the threshold, TCU will shift the transmission into neutral. The
operator has to slow down the vehicle and must shift the gear selector into neutral position.
(4) Transmission-shutdown
TCU has detected a severe failure that disables control of the transmission.
TCU will shut off the solenoid valves for the clutches and also the common power supply (VPS1).
Transmission shifts to neutral. The park brake will operate normally, also the other functions
which use ADM1 to ADM8.
The operator has to slow down the vehicle. The transmission will stay in neutral.
(5) TCU-shutdown
TCU has detected a severe failure that disables control of system.
TCU will shut off all solenoid valves and also both common power supplies (VPS1, VPS2). The
park brake will engage, also functions are disabled which use ADM 1 to ADM 8.
The transmission will stay in neutral.
※ Abbreviations
OC : Open circuit
SC : Short circuit
OP mode : Operating mode
TCU : Transmission control unit
EEC : Electronic engine controller
PTO : Power take off

3-31
 4) TRANSMISSION FAULT CODES
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
10 Logical error at direction select signal TCU shifts transmission to · Check the cables from TCU to shift
3rd shift lever neutral if selector active lever 3
T C U d e t e c t e d a w r o n g s i g n a l OP mode : Transmission · Check signal combinations of shift
combination for the direction shutdown if lever positions F-N-R
·Cable from shift lever 3 to TCU is broken selector active · If shift lever is a CAN shift lever
·Cable is defective and is contacted to check CAN cable/shifter/device
battery voltage or vehicle ground ※ Fault is cleared if TCU detects a
·Shift lever is defective valid neutral signal for the direction
at the shift lever
11 Logical error at gear range signal TCU shifts transmission to · Check the cables from TCU to shift
TCU detected a wrong signal combination neutral lever
for the gear range OP mode : Transmission · Check signal combinations of shift
·Cable from shift lever to TCU is broken shutdown lever positions for gear range
·Cable is defective and is contacted to ※ Failure cannot be detected in
battery voltage or vehicle ground systems with DW2/DW3 shift lever.
·Shift lever is defective Fault is taken back if TCU detects a
valid signal for the position
12 Logical error at direction select signal TCU shifts transmission to · Check the cables from TCU to shift
TCU detected a wrong signal combination neutral lever
for the direction OP mode : Transmission · Check signal combinations of shift
·Cable from shift lever to TCU is broken shutdown lever positions F-N-R
·Cable is defective and is contacted to ※ Fault is taken back if TCU detects a
battery voltage or vehicle ground valid signal for the direction at the
·Shift lever is defective shift lever
13 Logical error at engine derating device After selecting neutral, · Check engine derating device
TCU detected no reaction of engine while TCU change to OP mode ※ This fault is reset after power up of
derating device active limp home TCU
15 Logical error at direction select signal 2 TCU shifts transmission to · Check the cables from TCU to shift
shift lever neutral if selector active lever 2
TCU detected a wrong signal combination OP mode : Transmission · Check signal combinations of shift
for the direction shutdown if lever positions F-N-R
·Cable from shift lever 2 to TCU is broken elector active ※ Fault is taken back if TCU detects a
·Cable is defective and is contacted to valid neutral signal for the direction
battery voltage or vehicle ground at the shift lever
·Shift lever is defective
17 S.C. to ground at customer specific Customer specific · Check the cable from TCU to
function No. 1 (ride control) customer specific function No. 1
TCU detected a wrong voltage at the device
output pin, that looks like a S.C. to vehicle · C h e ck t h e c o n n e c t o r s f r o m
ground customer specific function No. 1 to
·Cable is defective and is contacted to TCU
vehicle ground · Check the resistance of customer
·Customer specific function No. 1 device specific function No. 1 device
has an internal defect
·Connector pin is contacted to vehicle
ground
※ Some fault codes are not applied to this machine.

3-32
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
18 S.C. to battery voltage at customer specific Customer specific · Check the cable from TCU to
function No. 1 (ride control) customer specific function No. 1
TCU detected a wrong voltage at the device
output pin, that looks like a S.C. to battery · C h e ck t h e c o n n e c t o r s f r o m
voltage customer specific function No. 1 to
·Cable is defective and is contacted to TCU
battery voltage · Check the resistance of customer
·Customer specific function No. 1 device specific function No. 1 device
has an internal defect
·Connector pin is contacted to battery
voltage
19 O.C. at customer specific function No. 1 Customer specific · Check the cable from TCU to
(ride control) customer specific function No. 1
TCU detected a wrong voltage at the device
output pin, that looks like a O.C. for this · C h e ck t h e c o n n e c t o r s f r o m
output pin customer specific function No. 1
·C a b l e i s d e fe c t i ve a n d h a s n o device to TCU
connection to TCU · Check the resistance of customer
·Customer specific function No. 1 device specific function No. 1 device
has an internal defect
·Connector has no connection to TCU
21 S.C. to battery voltage at clutch cut off Clutch cut off function is · Check the cable from TCU to the
input disabled sensor
The measured voltage is too high: OP mode : Normal · Check the connectors
·Cable is defective and is contacted to · Check the clutch cut off sensor
battery voltage
·Clutch cut off sensor has an internal
defect
·Connector pin is contacted to battery
voltage
22 S.C. to ground or O.C. at clutch cut off Clutch cut off function is · Check the cable from TCU to the
input disabled sensor
The measured voltage is too low: OP mode : Normal · Check the connectors
·Cable is defective and is contacted to · Check the clutch cut off sensor
vehicle ground
·Cable has no connection to TCU
·Clutch cut off sensor has an internal
defect
·Connector pin is contacted to vehicle
ground or is broken
25 S.C. to batter y voltage or O.C. at No reaction, TCU use · Check the cable from TCU to the
transmission sump temperature sensor default temperature sensor
input OP mode : Normal · Check the connectors
The measured voltage is too high: · Check the temperature sensor
·Cable is defective and is contacted to
battery voltage
·Cable has no connection to TCU
·Temperature sensor has an internal
defect
·Connector pin is contacted to battery
voltage or is broken
※ Some fault codes are not applied to this machine.

3-33
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
26 S.C. to batter y voltage or O.C. at No reaction, TCU uses · Check the cable from TCU to the
transmission sump temperature sensor default temperature sensor
input OP mode : Normal · Check the connectors
The measured voltage is too low: · Check the temperature sensor
·Cable is defective and is contacted to
vehicle ground
·Temperature sensor has an internal
defect
·Connector pin is contacted to vehicle
ground
27 S.C. to batter y voltage or O.C. at No reaction, TCU uses · Check the cable from TCU to the
retarder temperature sensor input default temperature sensor
The measured voltage is too high: OP mode : Normal · Check the connectors
·Cable is defective and is contacted to · Check the temperature sensor
battery voltage
·Cable has no connection to TCU
·Temperature sensor has an internal
defect
·Connector pin is contacted to battery
voltage or is broken
28 S.C. to ground at retarder temperature No reaction, TCU uses · Check the cable from TCU to the
sensor input default temperature sensor
The measured voltage is too low: OP mode : Normal · Check the connectors
·Cable is defective and is contacted to · Check the temperature sensor
vehicle ground
·Temperature sensor has an internal
defect
·Connector pin is contacted to vehicle
ground
31 S.C. to battery voltage or O.C. at engine OP mode : Substitute clutch · Check the cable from TCU to the
speed input control sensor
TCU measures a voltage higher than · Check the connectors
7.00V at speed input pin · Check the speed sensor
·Cable is defective and is contacted to
battery voltage
·Cable has no connection to TCU
·Speed sensor has an internal defect
·Connector pin is contacted to battery
voltage or has no contact
32 S.C. to ground at engine speed input OP mode : Substitute clutch · Check the cable from TCU to the
TCU measures a voltage less than 0.45V control sensor
at speed input pin · Check the connectors
·Cable/connector is defective and is · Check the speed sensor
contacted to vehicle ground
·Speed sensor has an internal defect
33 Logical error at engine speed input OP mode : Substitute clutch · Check the cable from TCU to the
TCU measures a engine speed over a control sensor
threshold and the next moment the · Check the connectors
measured speed is zero · Check the speed sensor
·Cable/connector is defective and has · Check the sensor gap
bad contact ※ This fault is reset after power up of
·Speed sensor has an internal defect TCU
·Sensor gap has the wrong size
※ Some fault codes are not applied to this machine.

3-34
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
34 S.C. to battery voltage or O.C. at turbine OP mode : Substitute clutch · Check the cable from TCU to the
speed input control sensor
TCU measures a voltage higher than If a failure is existing at · Check the connectors
7.00V at speed input pin output speed, · Check the speed sensor
·Cable is defective and is contacted to TCU shifts to neutral
vehicle battery voltage OP mode : Limp home
·Cable has no connection to TCU
·Speed sensor has an internal defect
·Connector pin is contacted to battery
voltage or has no contact
35 S.C. to ground at turbine speed input OP mode : Substitute clutch · Check the cable from TCU to the
TCU measures a voltage less than 0.45V control sensor
at speed input pin If a failure is existing at · Check the connectors
·Cable/connector is defective and is output speed, · Check the speed sensor
contacted to vehicle ground TCU shifts to neutral ※ This fault is reset after power up of
·Speed sensor has an internal defect OP mode : Limp home TCU
36 Logical error at turbine speed input OP mode : Substitute clutch · Check the cable from TCU to the
TCU measures a turbine speed over a control sensor
threshold and at the next moment the If a failure is existing at · Check the connectors
measured speed is zero output speed, · Check the speed sensor
·Cable/connector is defective and has TCU shifts to neutral · Check the sensor gap
bad contact OP mode : Limp home
·Speed sensor has an internal defect
·Sensor gap has the wrong size
37 S.C. to battery voltage or O.C. at internal OP mode : Substitute clutch · Check the cable from TCU to the
speed input control sensor
TCU measures a voltage higher than · Check the connectors
7.00V at speed input pin · Check the speed sensor
·Cable is defective and is contacted to
vehicle battery voltage
·Cable has no connection to TCU
·Speed sensor has an internal defect
·Connector pin is contacted to battery
voltage or has no contact
38 S.C. to ground at turbine speed input OP mode : Substitute clutch · Check the cable from TCU to the
TCU measures a voltage less than 0.45V control sensor
at speed input pin · Check the connectors
·Cable/connector is defective and is · Check the speed sensor
contacted to vehicle ground
·Speed sensor has an internal defect
39 Logical error at internal speed input OP mode : Substitute clutch · Check the cable from TCU to the
TCU measures a internal speed over a control sensor
threshold and at the next moment the · Check the connectors
measured speed is zero · Check the speed sensor
·Cable/connector is defective and has · Check the sensor gap
bad contact ※ This fault is reset after power up of
·Speed sensor has an internal defect TCU
·Sensor gap has the wrong size
3A S.C. to battery voltage or O.C. at output Special mode for gear · Check the cable from TCU to the
speed input selection sensor
TCU measures a voltage higher than OP mode : S u b s t i t u t e · Check the connectors
12.5V at speed input pin clutch control · Check the speed sensor
·Cable is defective and is contacted to If a failure is existing at
battery voltage turbine speed,
·Cable has no connection to TCU TCU shifts to neutral
·Speed sensor has an internal defect OP mode : Limp home
·Connector pin is contacted to battery
voltage or has no contact
※ Some fault codes are not applied to this machine.

3-35
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
3B S.C. to ground at output speed input Special mode for gear · Check the cable from TCU to the
TCU measures a voltage less than 1.00V selection sensor
at speed input pin OP mode : Substitute clutch · Check the connectors
·Cable/connector is defective and is control · Check the speed sensor
contacted to vehicle ground If a failure is existing at
·Speed sensor has an internal defect turbine speed,
TCU shifts to neutral
OP mode : Limp home
3C Logical error at output speed input Special mode for gear · Check the cable from TCU to the
TCU measures a turbine speed over a selection sensor
threshold and at the next moment the OP mode : Substitute clutch · Check the connectors
measured speed is zero control · Check the speed sensor
·Cable/connector is defective and has If a failure is existing at · Check the sensor gap
bad contact turbine speed, ※ This fault is reset after power up of
·Speed sensor has an internal defect TCU shifts to neutral TCU
·Sensor gap has the wrong size OP mode : Limp home
3D Turbine speed zero doesn't fit to other - · Not used
speed signals
3E Output speed zero doesn't fit to other Special mode for gear · Check the sensor signal of output
speed signals selection speed sensor
If transmission is not neutral and the OP mode : Substitute clutch · Check the sensor gap of output
shifting has finished, control speed sensor
TCU measures output speed zero and If a failure is existing at · Check the cable from TCU to the
turbine speed or internal speed not equal turbine speed, sensor
to zero. TCU shifts to neutral ※ This fault is reset after power up of
·Speed sensor has an internal defect OP mode : Limp home TCU
·Sensor gap has the wrong size
54 DCT1 timeout OP mode : Normal · Check display computer
Timeout of CAN-message DCT1 from · Check wire of CAN-Bus
display computer · Check cable to display computer
·Interference on CAN-Bus
·CAN wire/connector is broken
·CAN wire/connector is defective and
has contact to vehicle ground or battery
voltage
55 JSS timeout TCU shifts to neutral while · Check joystick steering controller
Timeout of CAN-message JSS from joystick steering is active · Check wire of CAN-Bus
joystick steering controller OP mode : Normal · Check cable to joystick steering
·Interference on CAN-Bus controller
·CAN wire/connector is broken
·CAN wire/connector is defective and
has contact to vehicle ground or battery
voltage
56 Engine CONF timeout OP mode : Substitute · Check engine controller
Timeout of CAN-message engine CONF clutch control · Check wire of CAN-Bus
from engine controller · Check cable to engine controller
·Interference on CAN-Bus
·CAN wire/connector is broken
·CAN wire/connector is defective and
has contact to vehicle ground or battery
voltage
※ Some fault codes are not applied to this machine.

3-36
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
57 EEC1 timeout OP mode : Substitute · Check EEC controller
Timeout of CAN-message EEC1 from clutch control · Check wire of CAN-Bus
EEC controller · Check cable to EEC controller
·Interference on CAN-Bus
·CAN wire/connector is broken
·CAN wire/connector is defective and
has contact to vehicle ground or battery
voltage
58 EEC3 timeout OP mode : Substitute · Check EEC controller
Timeout of CAN-message EEC3 from clutch control · Check wire of CAN-Bus
EEC controller · Check cable to EEC controller
·Interference on CAN-Bus
·CAN wire/connector is broken
·CAN wire/connector is defective an has
contact to vehicle ground or battery
voltage
5C Auto downshift signal No reaction · Check cluster controller
CAN signal for automatic downshift is · Check wire of CAN-Bus
defective · Check cable to cluster controller
·Cluster controller is defective
·Interference on CAN-Bus
5D Manual downshift signal No reaction · Check cluster controller
CAN signal for manual downshift is · Check wire of CAN-Bus
defective · Check cable to controller
·Cluster controller is defective
·Interference on CAN-Bus
5E CCO request signal No reaction · Check cluster controller
CAN signal for CCO request is defective · Check wire of CAN-Bus
·Cluster controller is defective · Check cable to controller
·Interference on CAN-Bus
61 AEB request signal No reaction · Check I/O controller, Omron master
CAN signal for AEB request is defective OP mode : Normal · Check wire of CAN-Bus
·I/O controller is defective · Check cable to I/O controller,
·Interference on CAN-Bus Omron master
64 Sarting gear signal No reaction. · Check I/O controller
CAN signal for starting gear is defective TCU uses default starting · Check wire of CAN-Bus
·I/O controller is defective gear · Check cable to I/O controller
(illegal starting gear) OP mode : Normal
·Interference on CAN-Bus
65 Engine torque signal OP mode : Substitute · Check engine controller
CAN signal for engine torque is defective clutch control · Check wire of CAN-Bus
·Engine controller is defective · Check cable to engine controller
·Interference on CAN-Bus
69 Reference engine torque signal OP mode : Substitute · Check engine controller
CAN signal for reference of engine torque clutch control · Check wire of CAN-Bus
is defective · Check cable to engine controller
·Engine controller is defective
·Interference on CAN-Bus
6A Actual engine torque signal OP mode : Substitute · Check engine controller
CAN signal for actual engine torque is clutch control · Check wire of CAN-Bus
defective · Check cable to engine controller
·Engine controller is defective
·Interference on CAN-Bus
※ Some fault codes are not applied to this machine.

3-37
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
6E EEC2 timeout No reaction, TCU uses · Check EEC controller
Timeout of CAN-message EEC2 from default signal accelerator · Check wire of CAN-Bus
EEC controller pedal in idle position · Check cable to EEC controller
·Interference on CAN-Bus OP mode : Normal
·CAN wire/connector is broken
·CAN wire/connector is defective and
has contact to vehicle ground or battery
voltage
71 S.C. to battery voltage at clutch K1 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home gearbox
is out of limit, the voltage at K1 valve is too If failure at another clutch · Check the connectors from TCU to
high is pending the gearbox
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to battery voltage OP mode : TCU shutdown · Check internal wire harness of the
·Cable/connector is defective and has gearbox
contact to another regulator output of * See page 3-49
the TCU
·Regulator has an internal defect
72 S.C. to ground at clutch K1 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home gearbox
is out of limit, the voltage at K1 valve is too If failure at another clutch · Check the connectors from gearbox
low is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to vehicle ground OP mode : TCU shutdown · Check internal wire harness of the
·Regulator has an internal defect gearbox
* See page 3-49
73 O.C. at clutch K1 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit If failure at another clutch · Check the connectors from gearbox
·Cable/connector is defective and has no is pending to TCU
contact to TCU TCU shifts to neutral · Check the regulator resistance*
·Regulator has an internal defect OP mode : TCU shutdown · Check internal wire harness of the
gearbox
* See page 3-49
74 S.C. to battery voltage at clutch K2 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit, the voltage at K2 valve If failure at another clutch · Check the connectors from gearbox
is too high is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to battery voltage OP mode : TCU shutdown · Check internal wire harness of the
·Cable/connector is defective and has gearbox
contact to another regulator output of * See page 3-49
the TCU
·Regulator has an internal defect
75 S.C. to ground at clutch K2 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home gearbox
is out of limit, the voltage at K2 valve is too If failure at another clutch · Check the connectors from gearbox
low is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to vehicle ground OP mode : TCU shutdown · Check internal wire harness of the
·Regulator has an internal defect gearbox
* See page 3-49
※ Some fault codes are not applied to this machine.

3-38
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
76 O.C. at clutch K2 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit If failure at another clutch · Check the connectors from gearbox
·Cable/connector is defective and has no is pending to TCU
contact to TCU TCU shifts to neutral · Check the regulator resistance*
·Regulator has an internal defect OP mode : TCU shutdown · Check internal wire harness of the
gearbox
* See page 3-49
77 S.C. to battery voltage at clutch K3 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit, the voltage at K3 valve If failure at another clutch · Check the connectors from gearbox
is too high is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to battery voltage OP mode : TCU shutdown · Check internal wire harness of the
·Cable/connector is defective and has gearbox
contact to another regulator output of * See page 3-49
the TCU
·Regulator has an internal defect
78 S.C. to ground at clutch K3 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home gearbox
is out of limit, the voltage at K3 valve is too If failure at another clutch · Check the connectors from gearbox
low is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to vehicle ground OP mode : TCU shutdown · Check internal wire harness of the
·Regulator has an internal defect gearbox
* See page 3-49
79 O.C. at clutch K2 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit If failure at another clutch · Check the connectors from gearbox
·Cable/connector is defective and has no is pending to TCU
contact to TCU TCU shifts to neutral · Check the regulator resistance*
·Regulator has an internal defect OP mode : TCU shutdown · Check internal wire harness of the
gearbox
* See page 3-49
7D S.C. ground at engine derating device Engine derating will be on · Check the cable from TCU to the
·Cable is defective and is contacted to until engine derating device
vehicle ground TCU power down even if · Check the connectors from engine
·Engine derating device has an internal fault vanishes (Loose derating device to TCU
defect connection) · Check the resistance* of engine
·Connector pin is contacted to vehicle OP mode : Normal derating device
ground ※ Not used
* See page 3-49
7E S.C. battery voltage at engine derating No reaction · Check the cable from TCU to the
device OP mode : Normal engine derating device
·Cable/connector is defective and is · Check the connectors from backup
contacted to battery voltage alarm device to TCU
·Engine derating device has an internal · Check the resistance* of backup
defect alarm device
* See page 3-49
※ Some fault codes are not applied to this machine.

3-39
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
7F O.C. at engine derating device No reaction · Check the cable from TCU to the
TCU detected a wrong voltage at the OP mode : Normal engine derating device
output pin, that looks like a O.C. for this · Check the connectors from engine
output pin derating device to TCU
·C a b l e i s d e fe c t i ve a n d h a s n o · Check the resistance* of engine
connection to TCU derating device
·Engine derating device has an internal * See page 3-49
defect
·Connector has no connection to TCU
81 S.C. to battery voltage at clutch K4 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit, the voltage at K4 valve If failure at another clutch · Check the connectors from gearbox
is too high is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to battery voltage OP mode : TCU shutdown · Check internal wire harness of the
·Cable/connector is defective and has gearbox
contact to another regulator output of * See page 3-49
the TCU
·Regulator has an internal defect
82 S.C. to ground at clutch K4 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home engine derating device
is out of limit, the voltage at K4 valve is too If failure at another clutch · Check the connectors from gearbox
low is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to vehicle ground OP mode : TCU shutdown · Check internal wire harness of the
·Regulator has an internal defect gearbox
* See page 3-49
83 O.C. at clutch K4 · Check the cable from TCU to the
The measured resistance value of the TCU shifts to neutral gearbox
valve is out of limit OP mode : Limp home · Check the connectors from gearbox
·Cable/connector is defective and has If failure at another clutch to TCU
contact to TCU is pending · Check the regulator resistance*
·Regulator has an internal defect TCU shifts to neutral · Check internal wire harness of the
OP mode : TCU shutdown gearbox
* See page 3-49
84 S.C. to battery voltage at clutch K4 TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit, the voltage at K4 valve If failure at another clutch · Check the connectors from gearbox
is too high is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to battery voltage OP mode : TCU shutdown · Check internal wire harness of the
·Cable/connector is defective and has gearbox
contact to another regulator output of * See page 3-49
the TCU
·Regulator has an internal defect
85 S.C. to ground at clutch KV TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home gearbox
is out of limit, the voltage at K4 valve is too If failure at another clutch · Check the connectors from gearbox
low is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to vehicle ground OP mode : TCU shutdown · Check internal wire harness of the
·Regulator has an internal defect gearbox
* See page 3-49
※ Some fault codes are not applied to this machine.

3-40
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
86 O.C. at clutch KV TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit If failure at another clutch · Check the connectors from gearbox
·Cable/connector is defective and has is pending to TCU
contact to TCU TCU shifts to neutral · Check the regulator resistance*
·Regulator has an internal defect OP mode : TCU shutdown · Check internal wire harness of the
gearbox
* See page 3-49
87 S.C. to battery voltage at clutch KR TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit, the voltage at KR valve is If failure at another clutch · Check the connectors from gearbox
too high is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to battery voltage OP mode : TCU shutdown · Check internal wire harness of the
·Cable/connector is defective and has gearbox
contact to another regulator output of the * See page 3-49
TCU
·Regulator has an internal defect
88 S.C. to ground at clutch KR TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the valve OP mode : Limp home gearbox
is out of limit, the voltage at KR valve is too If failure at another clutch · Check the connectors from gearbox
low is pending to TCU
·Cable/connector is defective and has TCU shifts to neutral · Check the regulator resistance*
contact to vehicle ground OP mode : TCU shutdown · Check internal wire harness of the
·Regulator has an internal defect gearbox
* See page 3-49
89 O.C. at clutch KR TCU shifts to neutral · Check the cable from TCU to the
The measured resistance value of the OP mode : Limp home gearbox
valve is out of limit If failure at another clutch · Check the connectors from gearbox
·Cable/connector is defective and has no is pending to TCU
contact to TCU TCU shifts to neutral · Check the regulator resistance*
·Regulator has an internal defect OP mode : TCU shutdown · Check internal wire harness of the
gearbox
* See page 3-49
91 S.C. to ground at relay reverse warning Backup alarm will be on · Check the cable from TCU to the
alarm until backup alarm device
TCU detected a wrong voltage at the TCU power down even if · Check the connectors from backup
output pin, that looks like a S.C. to vehicle fa u l t va n i s h e s ( L o o s e alarm device to TCU
ground connection) · Check the resistance* of backup
·Cable is defective and is contact to OP mode : Normal alarm device
vehicle ground * See page 3-49
·Backup alarm device has an internal
defect
·Connector pin is contacted to vehicle
ground
92 S.C. to battery voltage at relay reverse No reaction · Check the cable from TCU to the
warning alarm OP mode : Normal backup alarm device
TCU detected a wrong voltage at the · Check the connectors from backup
output pin, that looks like a S.C. to battery alarm device to TCU
voltage · Check the resistance* of backup
·Cable is defective and is contacted to alarm device
battery voltage * See page 3-49
·Backup alarm device has an internal
defect
·Connector pin is contacted to battery
voltage
※ Some fault codes are not applied to this machine.

3-41
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
93 O.C. at relay reverse warning alarm No reaction · Check the cable from TCU to the
TCU detected a wrong voltage at the OP mode : Normal backup alarm device
output pin, that looks like a O.C. for this · Check the connectors from backup
output pin alarm device to TCU
·C a b l e i s d e fe c t i ve a n d h a s n o · Check the resistance* of backup
connection to TCU alarm device
·Backup alarm device has an internal * See page 3-49
defect
·Connector has no connection to TCU
94 S.C. to ground at relay starter interlock No reaction · Check the cable from TCU to the
TCU detected a wrong voltage at the OP mode : Normal stater interlock relay
output pin, that looks like a S.C. to vehicle · Check the connectors from starter
ground interlock relay to TCU
·Cable is defective and is connection to · Check the resistance* of starter
vehicle ground interlock relay
·Starter interlock relay has an internal * See page 3-49
defect
·Connector pin is contacted to vehicle
ground
95 S.C. to battery voltage at relay starter No reaction · Check the cable from TCU to the
interlock OP mode : Normal starter interlock relay
TCU detected a wrong voltage at the · Check the connectors from starter
output pin, that looks like a S.C. to battery interlock relay to TCU
voltage · Check the resistance* of starter
·C a b l e i s d e fe c t i ve a n d h a s n o interlock relay
connection to battery voltage * See page 3-49
·Starter interlock relay has an internal
defect
·Connector pin is contacted to battery
voltage

96 O.C. at relay starter interlock No reaction · Check the cable from TCU to the
TCU detected a wrong voltage at the OP mode : Normal starter interlock relay
output pin, that looks like a O.C. for this · Check the connectors from starter
output pin interlock relay to TCU
·C a b l e i s d e fe c t i ve a n d h a s n o · Check the resistance* of starter
connection to TCU interlock relay
·Starter interlock relay has an internal * See page 3-49
defect
·Connector has no connection to TCU
9A S.C. to ground at conver ter lock up No reaction · Check the cable from TCU to the
clutch solenoid OP mode : Normal converter clutch solenoid
TCU detected a wrong voltage at the · C h e ck t h e c o n n e c t o r s f r o m
output pin, that looks like a S.C. to vehicle converter clutch solenoid to TCU
ground · Check the resistance* of converter
·Cable is defective and is contacted to clutch solenoid
vehicle ground * See page 3-49
·Conver ter clutch solenoid has an
internal defect
·Connector pin is contacted to vehicle
ground
※ Some fault codes are not applied to this machine.

3-42
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
9B O.C. at converter lock up clutch solenoid Converter clutch always · Check the cable from TCU to the
TCU detected a wrong voltage at the open, retarder not converter clutch solenoid
output pin, that looks like a O.C. for this available · C h e ck t h e c o n n e c t o r s f r o m
output pin OP mode : Normal converter clutch solenoid to TCU
·C a b l e i s d e fe c t i ve a n d h a s n o · Check the resistance* of converter
connection to TCU clutch solenoid
·Conver ter clutch solenoid has an * See page 3-49
internal defect
·Connector has no connection to TCU
9C S.C. to battery voltage at converter lock No reaction · Check the cable from TCU to the
up clutch solenoid OP mode : Normal converter clutch solenoid
TCU detected a wrong voltage at the · C h e ck t h e c o n n e c t o r s f r o m
output pin, that looks like a S.C. to battery converter clutch solenoid to TCU
voltage · Check the resistance* of converter
·Cable is defective and has no contacted clutch solenoid
to battery voltage * See page 3-49
·Conver ter clutch solenoid has an
internal defect
·Connector pin is contacted to battery
voltage
A1 S.C. to ground at difflock or axle No reaction · Check the cable from TCU to the
connection solenoid OP mode : Normal difflock solenoid
TCU detected a wrong voltage at the · Check the connectors from difflock
output pin, that looks like a S.C. to vehicle solenoid to TCU
ground · Check the resistance* of difflock
·Cable is defective and is contacted to solenoid
vehicle ground * See page 3-49
·Difflock solenoid has an internal defect
·Connector pin is contacted to vehicle
ground
A2 S.C. to battery voltage at difflock or axle No reaction · Check the cable from TCU to the
connection solenoid OP mode : Normal difflock solenoid
TCU detected a wrong voltage at the · Check the connectors from difflock
output pin, that looks like a S.C. to battery solenoid to TCU
voltage · Check the resistance* of difflock
·C a b l e i s d e fe c t i ve a n d h a s n o solenoid
connection to battery voltage * See page 3-49
·Difflock solenoid has an internal defect
·Connector pin is contacted to battery
voltage
A3 O.C. at difflock or axle connection No reaction · Check the cable from TCU to the
solenoid OP mode : Normal difflock solenoid
TCU detected a wrong voltage at the · Check the connectors from difflock
output pin, that looks like a O.C. for this solenoid to TCU
output pin · Check the resistance* of difflock
·C a b l e i s d e fe c t i ve a n d h a s n o solenoid
connection to TCU * See page 3-49
·Difflock solenoid has an internal defect
·Connector has no connection to TCU
※ Some fault codes are not applied to this machine.

3-43
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
A4 S.C. to ground at warning signal output No reaction · Check the cable from TCU to the
TCU detected a wrong voltage at the OP mode : Normal warning device
output pin, that looks like a S.C. to vehicle · Check the connectors from warning
ground device to TCU
·Cable is defective and is contacted to · Check the resistance* of warning
vehicle ground device
·Warning device has an internal defect * See page 3-49
·Connector pin is contacted to vehicle
ground
A5 O.C. voltage at warning signal output No reaction · Check the cable from TCU to the
TCU detected a wrong voltage at the OP mode : Normal warning device
output pin, that looks like a O.C. for this · Check the connectors from warning
output pin device to TCU
·C a b l e i s d e fe c t i ve a n d h a s n o · Check the resistance* of warning
connection to TCU device
·Warning device has an internal defect * See page 3-49
·Connector has no connection to TCU
A6 S.C. to battery voltage at warning signal No reaction · Check the cable from TCU to the
output OP mode : Normal warning device
TCU detected a wrong voltage at the · Check the connectors from warning
output pin, that looks like a S.C. to battery device to TCU
voltage · Check the resistance* of warning
·Cable is defective and has is contacted device
to battery voltage * See page 3-49
·Warning device has an internal defect
·Connector pin is contacted to battery
voltage
B1 Slippage at clutch K1 TCU shifts to neutral · Check pressure at clutch K1
TCU calculates a differential speed at OP mode : Limp home · Check main pressure in the system
closed clutch K1. If this calculated value If failure at another clutch · Check sensor gap at internal speed
is out of range, TCU interprets this as is pending sensor
slipping clutch TCU shifts to neutral · Check sensor gap at output speed
·Low pressure at clutch K1 OP mode : TCU shutdown sensor
·Low main pressure · Check signal at internal speed
·Wrong signal at internal speed sensor sensor
·Wrong signal at output speed sensor · Check signal at output speed
·Wrong size of the sensor gap sensor
·Clutch is defective · Replace clutch
B2 Slippage at clutch K2 TCU shifts to neutral · Check pressure at clutch K2
TCU calculates a differential speed at OP mode : Limp home Check main pressure in the system
closed clutch K2. If this calculated value If failure at another clutch · Check sensor gap at internal speed
is out of range, TCU interprets this as is pending sensor
slipping clutch TCU shifts to neutral · Check sensor gap at output speed
·Low pressure at clutch K2 OP mode : TCU shutdown sensor
·Low main pressure · Check signal at internal speed
·Wrong signal at internal speed sensor sensor
·Wrong signal at output speed sensor · Check signal at output speed
·Wrong size of the sensor gap sensor
·Clutch is defective · Replace clutch
※ Some fault codes are not applied to this machine.

3-44
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
B3 Slippage at clutch K3 TCU shifts to neutral · Check pressure at clutch K3
TCU calculates a differential speed at OP mode : Limp home · Check main pressure in the system
closed clutch K3. If this calculated value If failure at another clutch · Check sensor gap at internal speed
is out of range, TCU interprets this as is pending sensor
slipping clutch TCU shifts to neutral · Check sensor gap at output speed
·Low pressure at clutch K3 OP mode : TCU shutdown sensor
·Low main pressure · Check signal at internal speed
·Wrong signal at internal speed sensor sensor
·Wrong signal at output speed sensor · Check signal at output speed
·Wrong size of the sensor gap sensor
·Clutch is defective Replace clutch
B4 Slippage at clutch K4 TCU shifts to neutral · Check pressure at clutch K4
TCU calculates a differential speed at OP mode : Limp home Check main pressure in the system
closed clutch K4. If this calculated value If failure at another clutch · Check sensor gap at internal speed
is out of range, TCU interprets this as is pending sensor
slipping clutch TCU shifts to neutral · Check sensor gap at turbine speed
·Low pressure at clutch K4 OP mode : TCU shutdown sensor
·Low main pressure · Check signal at internal speed
·Wrong signal at internal speed sensor sensor
·Wrong signal at turbine speed sensor · Check signal at turbine speed
·Wrong size of the sensor gap sensor
·Clutch is defective Replace clutch
B5 Slippage at clutch KV TCU shifts to neutral · Check pressure at clutch KV
TCU calculates a differential speed at OP mode : Limp home · Check main pressure in the system
closed clutch KV. If this calculated value If failure at another clutch · Check sensor gap at internal speed
is out of range, TCU interprets this as is pending sensor
slipping clutch TCU shifts to neutral · Check sensor gap at turbine speed
·Low pressure at clutch KV OP mode : TCU shutdown sensor
·Low main pressure · Check signal at internal speed
·Wrong signal at internal speed sensor sensor
·Wrong signal at turbine speed sensor · Check signal at turbine speed
·Wrong size of the sensor gap sensor
·Clutch is defective · Replace clutch
B6 Slippage at clutch KR TCU shifts to neutral · Check pressure at clutch KR
TCU calculates a differential speed at OP mode : Limp home Check main pressure in the system
closed clutch KR. If this calculated value If failure at another clutch · Check sensor gap at internal speed
is out of range, TCU interprets this as is pending sensor
slipping clutch TCU shifts to neutral · Check sensor gap at turbine speed
·Low pressure at clutch KR OP mode : TCU shutdown sensor
·Low main pressure · Check signal at internal speed
·Wrong signal at internal speed sensor sensor
·Wrong signal at turbine speed sensor · Check signal at turbine speed
·Wrong size of the sensor gap sensor
·Clutch is defective · Replace clutch
B7 Overtemp sump No reaction · Cool down machine
TCU measured a temperature in the oil OP mode : Normal · Check oil level
sump that is over the allowed threshold. · Check temperature sensor
B9 Overspend engine Retarder applies
-
OP mode : Normal
BA Differential pressure oil filter No reaction · Check oil filter
TCU measured a voltage at differential OP mode : Normal · Check wiring from TCU to
pressure switch out of the allowed range differential pressure switch
·Oil filter is polluted · C h e ck d i f fe r e n t i a l p r e s s u r e
·Cable/connector is broken or cable/ switch(Measure resistance)
connector is contacted to battery voltage
or vehicle ground
·Differential pressure switch is defective
※ Some fault codes are not applied to this machine.
3-45
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
BB Slippage at converter lockup clutch No reaction · Check pressure at converter lockup
TCU calculates a differential speed at OP mode : Normal clutch
closed converter lockup clutch. If this · Check main pressure in the system
calculated value is out of range, TCU · Check sensor gap at engine speed
interprets this as slipping clutch sensor
·Low pressure at converter lockup clutch · Check sensor gap at turbine speed
·Low main pressure sensor
·Wrong signal at engine speed sensor · Check signal at engine speed
·Wrong signal at turbine speed sensor sensor
·Wrong size of the sensor gap · Check signal at turbine speed
·Clutch is defective sensor
· Replace clutch
C0 Engine torque or engine power overload OP mode : Normal
TCU calculates an engine torque or
e n g i n e p o w e r a b o ve t h e d e f i n e d
thresholds
C1 Transmission output torque overload OP mode : Normal
TCU calculates an transmission output
torque above the defined threshold
C2 Transmission input torque overload programmable :
TCU calculates an transmission input No reaction or shift to
torque above the defined threshold neutral
OP mode : Normal
C3 Overtemp converter output No reaction · Cool down machine
TCU measured a oil temperature at the OP mode : Normal · Check oil level
converter output that is the allowed · Check temperature sensor
threshold
C4 S. C. t o g r o u n d a t j oy s t i ck s t a t u s No reaction · Check the cable from TCU to
indicator OP mode : Normal joystick status indicator
TCU detected a wrong voltage at the · Check the connectors from joystick
output pin, that looks like a S.C. to vehicle status indicator to TCU
ground · Check the resistance* of joystick
·Cable is defective and is contacted to status indicator
vehicle ground * See page 3-49
·Joystick status indicator has an internal
defect
·Connector pin is contacted to vehicle
ground
C5 S.C. to battery voltage at joystick status No reaction · Check the cable from TCU to
indicator OP mode : Normal joystick status indicator
TCU detected a wrong voltage at the · Check the connectors from joystick
output pin, that looks like a S.C. to battery status indicator to TCU
voltage · Check the resistance* of joystick
·Cable is defective and is contacted to status indicator
battery voltage * See page 3-49
·Joystick status indicator has an internal
defect
·Connector pin is contacted to battery
voltage
※ Some fault codes are not applied to this machine.

3-46
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
C6 O.C. at joystick status indicator No reaction · Check the cable from TCU to
TCU detected a wrong voltage at the OP mode : Normal joystick status indicator
output pin, that looks like a O.C. for this · Check the connectors from joystick
output pin status indicator to TCU
·C a b l e i s d e fe c t i ve a n d h a s n o · Check the resistance* of joystick
connection to TCU status indicator
·Joystick status indicator has an internal * See page 3-49
defect
·Connector pin has no connection to
TCU
D1 S.C. to battery voltage at power supply See fault codes No.21 to · Check cables and connectors to
for sensors 2C sensors, which are supplied from
TCU measures more than 6V at the pin AU1
AU1 (5V sensor supply) · Check the power supply at the pin
AU1(Should be appx. 5V)
· Fault codes No.21 to No.2C may be
reaction of this fault
D2 S.C. to ground at power supply for See fault codes No.21 to · Check cables and connectors to
sensors 2C sensors, which are supplied from
TCU measures less than 4V at the pin AU1
AU1 (5V sensor supply) · Check the power supply at the pin
AU1(Should be appx. 5V)
· Fault codes No.21 to No.2C may be
reaction of this fault
D3 Low voltage at battery Shift to neutral · Check power supply battery
Measured voltage at power supply is lower OP mode : TCU shutdown · Check cables from batteries to TCU
than 18V(24V device) · Check connectors from batteries to
TCU
D4 High voltage at battery Shift to neutral · Check power supply battery
Measured voltage at power supply is OP mode : TCU shutdown · Check cables from batteries to TCU
higher than 32.5V(24V device) · Check connectors from batteries to
TCU
D5 Error at valve power supply VPS1 Shift to neutral · Check fuse
TCU switched on VPS1 and measured OP mode : TCU shutdown · Check cables from gearbox to TCU
VPS1 is off or TCU switched off VPS1 and · Check connectors from gearbox to
measured VPS1 is still on TCU
·Cable or connectors are defect and are · Replace TCU
contacted to battery voltage
·Cable or connectors are defect and are
contacted to vehicle ground
·Permanent power supply KL30 missing
·TCU has an internal defect
D6 Error at valve power supply VPS2 Shift to neutral · Check fuse
TCU switched on VPS2 and measured OP mode : TCU shutdown · Check cables from gearbox to TCU
VPS2 is off or TCU switched off VPS2 and · Check connectors from gearbox to
measured VPS2 is still on TCU
·Cable or connectors are defect and are · Replace TCU
contacted to battery voltage
·Cable or connectors are defect and are
contacted to vehicle ground
·Permanent power supply KL30 missing
·TCU has an internal defect
※ Some fault codes are not applied to this machine.

3-47
Fault code Meaning of the fault code Reaction of the TCU Possible steps to repair
(Hex) possible reason for fault detection
E3 S.C. to battery voltage at display output No reaction · Check the cable from TCU to the
TCU sends data to the display and OP mode : Normal display
measures always a high voltage level on · Check the connectors at the display
the connector · Change display
·Cable or connectors are defective and
are contacted to battery voltage
·Display has an internal defect
E4 S.C. to ground at display output No reaction · Check the cable from TCU to the
TCU sends data to the display and OP mode : Normal display
measures always a high voltage level on · Check the connectors at the display
the connector · Change display
·Cable or connectors are defective and
are contacted to battery voltage
·Display has an internal defect
E5 Communication failure on DeviceNet Shift to neutral · Check Omron master
OP mode : TCU shutdown · Check wire of DeviceNet-Bus
· Check cable to Omron master
F1 General EEPROM fault No reaction · Replace TCU
TCU can't read non volatile memory OP mode : Normal ※ Often shown together with fault
·TCU is defective code F2
F2 Configuration lost Transmission stay neutral · Reprogram the correct configurat-
TCU has lost the correct configuration and OP mode : TCU shutdown ion for the vehicle (e.g. with cluster
can't control the transmission controller,...)
·Interference during saving data on non
volatile memory
·TCU is brand new or from another
vehicle
F3 Application error Transmission stay neutral · Replace TCU
Something of this application is wrong OP mode : TCU shutdown ※ This fault occurs only if an test
engineer did something wrong in
the application of the vehicle
F5 Clutch failure Transmission stay neutral · Check clutch
AEB was not able to adjust clutch filling OP mode : TCU shutdown ※ TCU shows also the affected clutch
parameters on the display
·One of the AEB-Values is out of limit
F6 Clutch adjustment data lost No reaction, · Execute AEB
TCU was not able to read correct clutch Default values : 0 for AEB
adjustment parameters Offsets used
·Interference during saving data on non OP mode : Normal
volatile memory
·TCU is brand new
F7 Substitute clutch control OP mode : Substitute · Check engine retarder torque
·Transmission input torque wrong clutch control · Check speed sensors
·Engine retarder torque wrong
·Speed signal (s) defective
※ Some fault codes are not applied to this machine.

3-48
5) MEASURING OF RESISTANCE AT ACTUATOR/SENSOR AND CABLE
(1) Actuator

2 G
76043PT19

Open circuit R12 = R1G = R2G = ∞

Short cut to ground R12 = R; R1G = 0, R2G = R or R1G = R, R2G = 0
(For S.C. to ground, G is connected to vehicle ground)
Short cut to battery R12 = R; R1G = 0, R2G = R or R1G = R, R2G = 0
(For S.C. to battery, G is connected to battery voltage)

(2) Cable
UBat

P(Power supply)
TCU
1 2 Actuator/
Sensor

C(Chassis)

Ground
76043PT20

Open circuit R12 = R1P = R1C = R2P = R2C= ∞

Short cut to ground R12 = 0; R1C = R2C = 0, R1P = R2P = ∞
Short cut to battery R12 = 0; R1C = R2C = 0, R1P = R2P = 0

3-49
5. AXLE
1) OPERATION
· The power from the engine passes through torque converter, transmission and drive shafts, and is
then sent to the front and rear axles.
· Inside the axles, the power passes from the bevel pinion to the bevel gear and is sent at right
angles. At the same time, the speed is reduced and passes through the both differentials to the
axle shafts. The power of the axle shafts is further reduced by planetary-gear-type final drives and
is sent to the wheels.
(1) Front axle

74093PT10

1 Final drive 2 Differential 3 Axle

(2) Rear axle

3

74093PT11

1 Final drive 2 Differential 3 Axle

3-50
2) SECTION OF CONVENTIONAL DIFFERENTIAL (standard)

7403APT04

1 Bevel pinion 3 Side gear (differential) 5 Bevel gear

2 Shaft 4 Sun gear

3-51
3) SECTION OF LIMITED SLIP DIFFERENTIAL (option)
(1) Structure

1 2 3

6 5
7803ASPT15

1 Axle shaft 4 Clutch

2 Case 5 Side gear
3 Pinion gear 6 Pinion shaft

2) Operation

No driving When driving

N F

Ramp

Pinion shaft F
7803ASPT16

When the differential case is rotated, pinion shaft is moved up on the ramp by the resistance force of
tires as the figure, and then force P is generated. This force P becomes the engaging force of clutch.
① When travelling straight (equal resistance from road surface to left and right tires). Under this
condition, both clutch are engaged and the left and right side gears are driven with the same
force.
② When travelling on soft ground (resistance from road surface to right tire is smaller). At rotating
speed of right tire becomes faster than left due to the smaller resistance of right tive, right clutch
is engaged and torque of faster rotating right axle shaft is added to left axle shaft through
diffenenting gear case.

3-52
4) DIFFERENTIAL

(1) Description 3
When the machine makes a turn, the
2 4
outside wheel must rotate faster than the
inside wheel. A differential is a device
which continuously transmits power to the
right and left wheels while allowing them
to turn a different speeds, during a turn.
The power from the drive shaft passes
through bevel pinion (1) and is transmitted
to the bevel gear (2). The bevel gear
changes the direction of the motive force
by 90 degree, and at the same time
reduces the speed. 1
It then transmits the motive force through
the differential (3) to the axle gear shaft (4). 770-3 [3-26(1)]

(2) When driving straight forward

Pinion gear
When the machine is being driven straight
Side gear Side gear
forward and the right and left wheels are
rotating at the same speed, so the pinion Axle gear shaft
gear inside the differential assembly do
not rotate. The motive force of the carrier
is send through the pinion gear and the
side gear, therefore the power is equally Carrier
transmitted to the left and right axle gear Pinion gear
shaft.

770-3 [3-26(2)]

(3) When turning

Swing
When turning, the rotating speed of the
Pinion gear
left and right wheels is different, so the
Side gear Side gear
pinion gear and side gear inside the
differential assembly rotate in accordance
with the difference between the rotating
speed of the left and right wheels.
T h e p owe r o f t h e c a r r i e r i s t h e n
transmitted to the axle gear shafts. Carrier

Pinion gear Ring gear

770-3 [3-26(3)]

3-53
6) FINAL DRIVE (front & rear)

1 2 3

73093PT17

1 Axle shaft 2 Ring gear

3 Planetary gear

(1) To gain a large drive force, the final drive uses a planetary gear system to reduce the speed and
send drive force to the tires.
(2) The power transmitted from the differential through axle shaft (1) is transmitted to planetary gear
(3). The planetary gear rotates around the inside of a fixed ring gear (2) and in this way transmits
rotation at a reduced speed to the planetary carrier.
This power is then sent to the wheels which are installed to the planetary carriers.

3-54
6. TIRE AND WHEEL

7407APT10

1 Wheel rim 3 O-ring 5 Side ring

2 Tire 4 Lock ring 6 Valve assembly

1) The tire acts to absorb the shock from the ground surface to the machine, and at the same time
they must rotate in contact with the ground to gain the power which drives the machine.
2) Various types of tires are available to suit the purpose. Therefore it is very important to select the
correct tires for the type of work and bucket capacity.

3-55
GROUP 2 OPERATIONAL CHECKS AND TROUBLESHOOTING

1. POWER TRAIN OPERATIONAL CHECKS

This procedure is designed so that the mechanic can make a quick check of the system using a
minimum amount of diagnostic equipment. If you need additional information, read Structure and
function, Group 1.
A location will be required which is level and has adequate space to complete the checks.
The engine and all other major components must be at operating temperature for some checks.
Locate system check in the left column and read completely, following the sequence from left to right.
Read each check completely before performing.
At the end of each check, if no problem is found(OK), that check is complete or an additional check is
needed. If problem is indicated(NOT OK), you will be given repair required and group location.
If verification is needed, you will be given next best source of information :

Chapter 2 : Troubleshooting
Group 3 : Tests and adjustments

3-56
※ Transmission oil must be at operating temperature for these checks.

Item Description Service action

Transmission oil warm-up Start engine. Apply service brakes OK
procedure and release parking brake. Check completed.
Select T/M shift mode switch to
MAN (manual) mode.
Move gear selector lever to 3rd
speed.
Move gear selector lever to forward
"F" position.
Increase engine speed to high idle
AL MAN

for 30 seconds.
AN AH
A
Move gear selector lever to neutral
"N" position and r un for 15
seconds.
1

4
2
3
Repeat procedure until
transmission temperature gauge
arrow points to bar above dial.
Gear selector lever and Move gear selector lever to each OK
neutral lock latch checks position. Check completed.
Engine OFF. 1

NOTE : Gear selector lever position

2
3
4

NOT OK
changes slightly as steer ing
Repair lock or replace
column is tilted.
switch.
FEEL : Lever must move freely
through all positions.
Engage neutral lock.
Apply slight effort to move lever into
forward (F) and reverse (R).
LOOK : Neutral lock must stay
engaged.
Automatic shifting check Start engine. OK
Check completed.
1
2
3
F
N
Move gear selector lever to 4th
4
R
speed.
NOT OK
Turn T/M shift mode switch to AL Go to transmission error
(auto light) mode. code group at page 3-32~
3-48.
Auotmatic sign LOOK : Automatic sign on monitor.
Repair or replace the
Move gear selector lever to forward monitor or harness.
or reverse position.
Increase engine rpm.
LOOK : Speed on monitor must
vary with machine speed.

3-57
 Item Description Service action
Transmission noise Run engine at approximately 1600 OK
check 1
2
rpm. Check completed.
3

Engine running.
4

Drive unit with transmission in each NOT OK

forward and reverse speed. Go to transmission makes
excessive noise, chapter 2
LISTEN : Transmission must not
in this group.
make excessive noise in any range.
Engine rpm must not "lug down" as
unit is shifted between gears.
Transmission "quick shift" Release parking brake and select OK
Release
check T/M shift mode switch to MAN Check completed.
Engine running. (manual) mode.
NOT OK
P

Shift to 2nd forward. Check connector at base

of control valve.
Drive machine at approximately
5km/h and press gear selector lever IF OK
kick down switch or RCV levers Go to transmission
switch once. controller circuit in group 1.
AL MAN

LOOK/FEEL : Transmission must

AN
A
AH
shift to and remain in 1st gear.
Press gear selector lever kick down
switch once.
1

4
2
3
LOOK/FEEL : Transmission must
shift back to 2nd gear.
Shift to (3rd or 4th) gear and press
gear selector lever kick down
switch once.
LOOK/FEEL : Transmission must
not shift down.
Select T/M shift mode switch to AL
(auto light) mode.
Drive machine at approximately
90% speed of max speed in each
gear (2nd or 3rd or 4th).
Shift to (2nd or 3rd or 4th) gear in
each forward and reverse speed
and press gear selector kick down
lever switch or RCV lever switch
once.
LOOK/FEEL : It shift down quickly
from current gear to one step lower
speed and recover to original
speed quickly when push the
switch one more time. (mode 1)

3-58
 Item Description Service action
LOOK/FEEL : If shifts down from
current gear to one step lower
speed when push the switch
everytime and recover when push
the switch in 1st gear. (mode 2)
Forward, reverse and 4th Park unit on level surface. OK
speed clutch pack drag 1
2
3 Check completed.
Apply service brakes.
4

check
NOT OK
※ Transmission must Move gear selector lever to neutral.
I f u n i t m ove s, r e p a i r
be warmed up for Release
Move gear selector lever to 1st. transmission.
this check.
Engine running. Release parking brake and service
P

brakes.
Run engine at low idle.
LOOK : Unit must not move in
either direction.
NOTE : If unit moves forward,
either the forward pack or the 4th
speed pack is dragging.
Transmission shift Run engine at approximately 1300 OK
modulation check 1

4
2
3 rpm. Check completed.
Engine running.
Put transmission in 1st forward, NOT OK
shift several times from forward to Go to unit shifts too fast,
reverse and reverse to forward. chapter 2 in this group.
Repeat check in 2nd gear.
LOOK : Unit must slow down and
change direction smoothly.
Torque converter check Start engine. Apply service brakes OK
1

4
2
3
and release parking brake. Check completed.
Move gear selector lever to 3rd NOT OK
speed. If stall rpm are too low or
too high, problem may be
Move gear selector control lever to
engine power or torque
forward "F" position.
converter.
Increase engine speed to high idle.
IF OK
LOOK : Torque converter stall rpm Replace transmission
must be within the following range. torque converter.
Stall rpm : 1950±70 rpm
Move gear selector control lever to
neutral "N" position and run for 15
seconds.

3-59
2. TROUBLESHOOTING
1) TRANSMISSION
※ Diagnose malfunction charts are arranged from most probable and simplest to verify, to least likely,
more difficult to verify. Remember the following steps when troubleshooting a problem :
Step 1. Operational check out procedure (See group 3 in section 1.)
Step 2. Operational checks (In this group.)
Step 3. Troubleshooting
Step 4. Tests and/or adjustments (See group 3.)

Problem Cause Remedy

Transmission slippage Low oil level. Add oil.
Wrong oil grade. Change oil.
Restricted transmission pump Remove and clean screen.
suction screen.
Leak in transmission control valve Remove valve and inspect gaskets.
or gasket.
Low transmission pump flow due Do transmission pump flow test.
to worn pump.
Weak or broken pressure regulat- Do transmission system pressure test.
ing valve spring.
Error code on display Something wrong in transmission. Go to transmission error code group at page
3-32~3-48.

3-60
 Problem Cause Remedy
Machine will not move Low oil level. Add oil.
Applied park brake. Check parking brake fuse.
Check continuity to parking brake switch.
No power to transmission contro- Check transmission controller fuse.
ller.
Malfunctioning parking brake Remove and inspect parking brake solenoid
solenoid valve. valve.
Check for power to solenoid valve.
Restricted orifice of PPC valve. Remove orifice and check for contamination
and/or plugging.
(Do not remove valve housing for this purpose.)
Excessive leakage in Do transmission element leakage test using
transmission element. system pressure.
Worn clutch disks. Repair transmission.
Low or no transmission See transmission pressure is low in this group.
pressure.
Service brake will not release. Do brake pedal operational check.
Do service and park system drag checks.
Failed torque converter. Do torque converter stall test.
If engine pulldown in normal, torque converter is
good.
Broken shafts or gears. Drain transmission to determine if large pieces
of metal contamination are present.
Broken drive shafts. Inspect drive shafts and universal joints for
external damage. Repair.

Broken ring or pinion gear. If drive shaft rotate with transmission in gear but
machine does not move, a differential failure is
indicated. Repair.
Machine does not Malfunctioning transmission Check solenoid valve.
engage in low gear control solenoid valve.
Stuck spool in transmission Remove and inspect transmission control valve
control valve. spools.
Stuck PPC valve. Remove end cover to inspect PPC valve.
Replace if necessary.
Malfunctioning transmission Check speed sensor.
speed sensor.

3-61
 Problem Cause Remedy
Transmission pressure is Low oil level. Check transmission oil level and refill if
low (all gears) necessary.
Failed transmission pressure Verify transmission system pressure. Do
switch. transmission system pressure test.
Plugged suction strainer. Transmission pump may be noisy if transmission
suction screen is clogged. Drain transmission.
Remove and clean suction screen.
Also, check condition of transmission filter.
Stuck transmission pressure Remove transmission pressure regulating valve.
regulating valve or broken spring. Inspect for damage (See transmission control
valve).
Failed control valve gasket. Inspect transmission control valve for external
leakage. Remove control valve.
Inspect or replace gasket.
Stuck PPC valve. Remove end cover to inspect modulation spool
and check torque on cap screws retaining
control valve to transmission.
Tr a n s m i s s i o n s y s t e m Failed transmission pump. Do pump flow test.
pressure is low (one or
Failed transmission control valve Inspect transmission control valve for external
two gears)
gasket. leakage. Remove control valve.
Inspect or replace gasket.
Leakage in clutch piston or seal Disassemble and repair.
ring.
Transmission shifts too Low oil level (aeration of oil). Add oil.
low
Low transmission pressure. Do transmission system pressure test.
Restricted transmission pump Remove and clean screen.
suction screen.
Low transmission pump flow. Do transmission pump flow test.
Excessive transmission Do transmission element leakage test using
element leakage. system pressure.
Stuck PPC valve. Remove end cover to inspect modulation spool.
Replace if necessary.
Restricted PPC valve orifice. Remove orifice and inspect for contamination
and /or plugging.
Restricted oil passages between Remove control valve and inspect oil passage.
control valve and transmission
elements.
Incorrect transmission oil. Change oil (SAE 10W-30/15W-40)

3-62
 Problem Cause Remedy
Transmission shifts too Wrong transmission controller. Check if transmission controller has been
fast changed
System pressure too high. Do transmission system pressure test.
Stuck PPC valve. Remove and inspect PPC valve.
Replace if necessary. Also remove end cover
to inspect PPC valve and control valve housing.
Replace if necessary.
Stuck or missing check valves. Inspect transmission control valve.
Missing O-r ing from end of Remove orifice and inspect port for O-ring.
modulation orifice.
Broken piston return spring. Disassemble and inspect clutch.
Incorrect transmission oil. Change oil (SAE 10W-30/15W-40).
Machine "creeps" War ped disks and plates in Check transmission.
in neutral transmission.
Transmission hydraulic High oil level. Transmission overfilled or hydraulic pump seal
system overheats leaking.
Low oil level. Add oil.
Wrong oil grade. Change oil.
Park brake dragging. Check for heat in park brake area.
Pinched, restricted or leaking lube Check cooler lines.
lines.
Machine operated in too high Operate machine in correct gear range.
gear range.
Malfunction in temperature gauge I n s t a l l t e m p e ra t u r e s e n s o r t h e ve r i f y
or sensor. temperature.
Do tachometer/temperature reader installation
procedure.
Restricted air flow through oil Do radiator air flow test.
cooler or radiator.
Failed oil cooler bypass valve (In Disassemble and inspect.
thermal bypass valve).
Failed thermal bypass valve. Remove thermal bypass valve and check to see
if machine still overheats. Do transmission oil
cooler thermal bypass valve test.
Internally restricted oil cooler. Do oil cooler restriction test.
Leakage in transmission hydraulic Do transmission system pressure, element
system. leakage test.
Malfunction in converter relief Do converter out pressure test.
valve.
Low transmission pump output. Do transmission pump flow test.

3-63
 Problem Cause Remedy
Excessive transmission Too low engine low idle. Check engine low idle speed.
noise (Under load or no
Wo r n p a r t s o r d a m a g e d i n Remove transmission suction screen. Inspect
load)
transmission. for metal particles.
Repair as necessary.
Warped drive line between engine Inspect drive line.
and torque converter.
Low or no lube. Do converter-out and lube pressure test. Do
transmission pump flow test.
Foaming oil Incorrect type of oil. Change oil.
High oil level. Transmission overfilled or hydraulic pump seal
leaking.
Low oil level. Add oil.
Air leak on suction side of pump. Check oil pickup tube on side of transmission.
Oil ejected from dipstick Plugged breather. Inspect breather on top of transmission.
Replace.
Machine vibrates Aerated oil. Add oil.
Low engine speed. Check engine speed.
Fa i l e d u n i ve r s a l j o i n t s o n Check universal joints.
transmission dr ive shaft or
differential drive shafts.
Machine lacks power and Engine high idle speed set too Check high idle adjustment.
acceleration low.
Incorrect transmission oil. Change oil.
Aerated oil. Add oil.
Low transmission pressure. Do transmission system pressure test.
Warped transmission clutch. Do transmission clutch drag checks.
Torn transmission control valve Inspect gasket.
gasket.
Brake drag. Do brake drag check.
Failed torque converter. Do torque converter stall speed test.
Low engine power. Do engine power test.
Torque conver ter stall Aerated oil. Put clear hose on thermal bypass outlet port.
RPM too high Run machine to check for bubbles in oil.
Stuck open converter relief valve. Do converter-out pressure test.
Leakage in torque converter seal. Do converter-out pressure test.
Torque converter not Replace torque converter.
transferring power (Bent fins,
broken starter).

3-64
 Problem Cause Remedy
Torque conver ter stall Low engine power. Do engine power test.
RPM too low
Mechanical malfunction. Remove and inspect torque converter.
Transmission pressure Low oil level. Add oil.
light comes ON when
Cold oil. Warm oil to specification.
shifting from forward to
reverse (all other gears Leak in reverse pack. Do transmission pressure, pump flow, and
OK) leakage check.
Transmission pressure Cold oil. Warm oil to specification.
light comes ON for each
No time delay in monitor. Do monitor check.
shift
Restriction in modulation orifice. Remove orifice and inspect for restriction and/or
plugging.
Stuck PPC valve. Remove and inspect.
Low transmission pressure circuit. Do transmission system pressure test.

Leak in transmission pressure Do converter out pressure test.

circuit.
Failed transmission pump. Do transmission pump flow test.
Clogged filter. Inspect filter. Replace.

3-65
 2) DIFFERENTIAL / AXLE
Problem Cause Remedy
Differential low on oil External leakage. Inspect axle and differential for leaks.
Excessive differential Low oil level in differential. Check oil. Remove drain plug and inspect for
and/or axle noise metal particles in differential case.
Disassemble and determine cause.
Incorrect type of oil. Change oil
Dragging brakes. Do brake check.
Failed pinion bearing. Remove and inspect pinion.
Check to ensure pinion housing was indexed.
Incorrect gear mesh pattern Remove pinion gear housing and inspect ring
between ring and pinion gear. and pinion gear.
Failed differential pinion gears Remove differential housing drain plug and
and/or cross shafts. inspect for metal particles. Disassemble and
inspect.
Failed axle bearing. Do axle bearing adjustment check.
M e c h a n i c a l fa i l u r e i n a x l e Remove differential. Inspect, repair.
planetary.
Oil seeping from outer Excessive end play in axle. Do axle bearing adjustment check.
axle seal
Worn outer bearing and/or cup. Disassemble and inspect outer axle bearing,
cup, spacer, and seal. Replace, if necessary.
Overfilled differential. Check differential oil return system for
excessive internal restriction.
Axle overheats Low differential oil. Add oil.
Overfilled differential. See differential overfills with oil in this group.
Brake drag. See brakes drag in this group.

3) DRIVE LINE
Problem Cause Remedy
E x c e s s i v e d r i v e l i n e Yokes not in line on drive shafts. Inspect. Align drive shaft yokes.
vibration or noise
Worn front drive line support Inspect, repair.
bearing.
Bent drive shaft. Inspect all drive shafts. Replace.
Loose yoke retaining nuts (drive Inspect. Replace.
shafts wobble at high speed).
Rear axle oscillating support. Inspect, repair.
Lack of lubrication. Lubricate with proper grade of grease.

3-66
GROUP 3 TESTS AND ADJUSTMENTS

1. TRANSMISSION MEASURING POINTS AND CONNECTIONS

The measurements have to be carried out at hot transmission (about 80~95˚C).
48 47 21

54

34
65 51 68

69 49
H J
K
G

57 60
A F

B E 16
53 55 15
C D

58 56 52,63

VIEW X VIEW Y
7407APT15

1) OIL PRESSURE AND TEMPERATURE

Port Description Size
51 Converter inlet-opening pressure (11 bar) H M10×1
52 Converter outlet-opening pressure (4.3 bar) M14×1.5
53 Forward clutch (16+2 bar) B M10×1
55 Reverse clutch (16+2 bar) E M10×1
56 1st clutch (16+2 bar) D M10×1
57 2nd clutch (16+2 bar) A M10×1
58 3rd clutch (16+2 bar) C M10×1
60 4th clutch (16+2 bar) F M10×1
63 Converter outlet temperature 100˚C, short-time 120˚C M14×1.5
65 System pressure (16+2 bar) K M10×1

3-67
2) DELIVERY RATES
Port Description Size
15 Connection to the oil cooler 1 5/16″-12UN
16 Connection from the oil cooler 1 5/16″-12UN

3) INDUCTIVE TRANSMITTER AND SPEED SENSOR

Port Description Size
21 Inductive transmitter n turbine M18×1.5
34 Speed sensor n output and speedometer -
47 Inductive transmitter n central gear train M18×1.5
48 Inductive transmitter n engine M18×1.5
54 Filter contamination switch M14×1.5

4) CONNECTIONS
Port Description Size
49 Plug connection on the hydraulic control unit -
68 Pilot pressure (option) J M16×1.5
69 System pressure (option) G M16×1.5

3 - 68
GROUP 4 DISASSEMBLY AND ASSEMBLY

1. CONTROL VALVE
1) DISASSEMBLY
(1) Illustration on the right shows the
complete control unit.

73073CV001

(2) Mark the installation position of the

different covers, the housing and cable
harness with the valve housing.

73073CV002

(3) Loosen socket head screws.

S e p a ra t e d u c t p l a t e, 1 s t g a s ke t ,
intermediate plate and 2nd gasket from
the valve housing.
※ Special tool
Box spanner 5873 042 002

73073CV003

(4) Remove retaining clip.

73073CV004

3-69
(5) Loosen socket head screws.
Separate cover from housing and cable
harness.
※ Special tool
Box spanner 5873 042 002

73073CV005

(6) Disassemble opposite cover.

Disconnect pressure regulator and
remove cable harness.

73073CV006

(7) Loosen socket head screws, remove

fixing plate and pressure regulators (3EA).
※ Special tool
Box spanner 5873 042 002

73073CV007

(8) Loosen two socket head screws and

locate housing provisionally, using
adjusting screws(Housing is under spring
preload).
Now, loosen remaining socket head
screws.
※ Special tool
Box spanner 5873 042 002
Adjusting screws 5870 204 036
73073CV008

3-70
(9) Separate housing from valve housing by
loosening the adjusting screws uniformly.
※ Special tool
Adjusting screws 5870 204 036

73073CV009

(10) Remove components.

73073CV010

(11) Remove opposite pressure regulators,

housing as well as components
accordingly.

73073CV011

3-71
2) ASSEMBLY
※ Check all components for damage and
renew if necessary.
Prior to the installation, check free travel of
all moving parts in the housing.
Spools can be exchanged individually.
Oil the components prior to the assembly.
Insert diaphragms with the concave side
showing upward until contact is obtained.
※ Installation position, see arrows.
73073CV015

(1) Illustration on the right shows the following

components.
1 Vibration damper
2 Follow-on slide
3 Pressure reducing valve

73073CV016

(2) Install components according to figure (1).

※ Preload compression spring of the follow-
on slides and locate spool provisionally by
means of cylindrical pins Ø5.0 mm
(assembly aid), see arrows.

73073CV017

(3) Install two adjusting screws.

Assemble gasket (arrow 1) and housing
cover. Now, position the housing cover
uniformly, using adjusting screws, until
contact is obtained and remove cylindrical
pinss(assembly aid) again (see the next
figure).
※ Pay attention to the different housing covers.
Install recess Ø15 mm (arrow 2), facing
the spring of the pressure reducing valve.
Adjusting screws 5870 204 036 73073CV018

3-72
 73073CV019

(4) Fasten housing cover by means of socket

head screws.
·Torque limit : 0.56 kgf·m (4.06 lbf·ft)
※ Special tool
Box spanner 5873 042 002

73073CV020

(5) Introduce pressure regulators and fix by

means of fixing plates and socket head
screws.
※ Install fixing plate, with the claw showing
downward.
Pay attention to the radial installation
position of the pressure regulators, see
figure.
·Torque limit : 0.56 kgf·m (4.06 lbf·ft)
※ Special tool 73073CV021
Box spanner 5873 042 002

Pre assemble opposite side

(6) Illustration on the right shows the following
components.
1 Main pressure valve
2 Follow on slide
3 Vibration damper

73073CV022

3-73
(7) Install components according to figure (6).
Preload compression springs of the
follow-on slides and locate spool
provisionally by means of cylindrical pins
Ø5.0 mm (assembly aid), see arrows.
Install two adjusting screws.
Assemble gasket (arrow 1) and housing
cover, and position them uniformly against
shoulder, using adjusting screws.
※ Pay attention to the different housing
covers-install the recess Ø19 mm (arrow 73073CV023
2), facing the main pressure valve.
Now, fasten housing cover by means of
socket head screws.
·Torque limit : 0.56 kgf·m (4.06 lbf·ft)
Remove cylindrical pins(Assembly aid)
again.
※ Special tool
Adjusting screws 5870 204 036
Box spanner 5873 042 002

(8) Introduce pressure regulators and fix by

means of fixing plates and socket head
screws.
※ Install fixing plates, with the claw showing
downward.
Pay attention to the radial installation
position of the pressure regulators, see
figure.
※ Special tool
·Torque limit : 0.56 kgf·m (4.06 lbf·ft)
Box spanner 5873 042 002 73073CV024

(9) Introduce cable harness and connect

pressure regulators (6EA).
※ Pay attention to the installation position of
the cable harness, see also markings
(see figure (2), page 3-69).

73073CV025

3-74
(10) Introduce female connector against
shoulder, with the groove facing the guide
nose of the cover.
Install gasket (arrow) and fasten cover by
means of socket head screws.
·Torque limit : 0.56 kgf·m (4.06 lbf·ft)
※ Special tool
Box spanner 5873 042 002

73073CV026

(11) Fix female connector by means of

retaining clamp, see figure.
Install opposite cover.

73073CV027

(12) Install two adjusting screws and mount

gasket Ⅰ.
※ Pay attention to the different gaskets, see
on the right figure and (15).
※ Special tool
Adjusting screws 5870 204 063

73073CV028

Intermediate plate-Version with screens

(13) Insert screws (6EA) flush mounted into
the bore of the intermediate plate, see
arrow.
※ Pay attention to the installation position-
screws are showing upward (facing the
duct plate).

73073CV029

3-75
(14) Mount intermediate plate, with the
screens showing upward.

73073CV030

(15) Mount gasket Ⅱ.

73073CV031

(16) Mount duct plate and fasten it uniformly by

means of socket head screws.
·Torque limit : 0.97 kgf·m (7.0 lbf·ft)
※ Special tool
Box spanner 5873 042 002

73073CV032

(17) Equip screw plug (8EA) with new O-rings

and install them.
·Torque limit : 0.61 kgf·m (4.43 lbf·ft)
※ The installation of the hydraulic control
unit is described, starting from page
3-130.

73073CV033

3-76
2. TRANSMISSION
1) DISASSEMBLY
(1) Remove filter unit
① Demount warning switch (arrow) from
filter head.

73073TM002

② Separate oil filter from filter head.

※ Special tool
Belt spanner 5870 105 005

73073TM003

③ Loosen hexagon head screws and

separate filter head from duct plate.

73073TM004

(2) Separate hydraulic control unit and duct

plate from gearbox housing
① Loosen socket head screws, install two
adjusting screws and separate control
unit from duct plate.
※ Special tool
Adjusting screw 5870 204 031

73073TM004

3-77
 ② Remove both gaskets as well as
intermediate plate.
※ Special tool
Adjusting screws 5870 204 031

75773TM051

③ Loosen socket head screws and

hexagon nuts and separate duct plate
from gearbox housing.
Now, remove flat gasket.
※ Special tool
Adjusting screws 5870 204 031

75773TM052

(3) Remove and disassemble converter

safety valve
① Pull converter safety valve out of the
housing bore.

75773TM053

② Illustration on the right shows the

required special tool for the
disassembling of the converter safety
valve.
1 Converter safety valve
※ Special tool
Assembly aid 5870 345 084

73073TM009

3-78
 ③ Preload compression spring carefully,
remove cylindrical pin (see on the right
figure) and demount components (see
on the below figure).

73073TM010

73073TM011

(4) Engine connection-Converter

① Remove lock plate and loosen hexagon
head screws.
Remove disk and pry input flange from
the shaft.

73073TM015

② Loosen screw connection.

※ Mark radial installation position of the
housing cover.

73073TM016

3-79
③ Separate cover along with converter from
the transmission, using lifting device.
※ Special tool
Set of eye bolts 5870 204 002

75773TM057

④ Press input shaft, respectively converter

out of the cover (ball bearing).

75773TM058

⑤ Squeeze circlip out and remove ball

bearing.
※ Special tool
Set of internal pliers 5870 900 013

75773TM059

⑥ Loosen hexagon head screws and

separate membrane from converter.

75773TM060

3-80
⑦ Loosen hexagon head screws and
separate input shaft from the membrane.

75773TM061

⑧ Remove inductive transmitter (n enging).

75773TM062

⑨ Loosen hexagon head screws and

remove converter housing.

75773TM063

(5) Remove transmission pump

① Loosen socket head screws.

75773TM064

3-81
 ② Apply separating device on the splines
runout of the stator shaft and pull pump
out of the housing bores, using two-leg
puller.
※ Special tool
Separating device 5870 300 024
Two-leg puller 5870 970 004

75773TM065

③ Separate transmission pump from stator.

Separate cam plate from pump.
※ If traces of wear should be encountered
in the pump housing or the cam disk, the
complete pump has to be renewed.
Now, fit cam disk again and fix it by
means of grooved pins (2EA).

75773TM066

④ Loosen hexagon head screws and

remove oil feed housing.
Now, remove flat gasket.

75773TM067

(6) Converter pressure valve

① Pull converter pressure valve out of the
housing bore.

73073TM028

3-82
 ② Illustration on the right shows the special
tool required for the disassembling of the
converter pressure valve.
1Converter pressure valve
※ Special tool
Assembly aid 5870 345 084

73073TM029

③ Preload compression spring carefully,

drive roll pin out and remove
components.
※ Special tool
Assembly aid 5870 345 084

73073TM030

④ Loosen hexagon head screws, demount

cover and remove flat gasket.

73073TM031

(7) Demount output, input and clutches

① Remove lock plate, loosen hexagon head
screws, and pry the converter-side
output flange from the shaft.
Now, pry shaft seal out of the housing
bore.
Tilt gearbox 180˚ and remove rear output
flange accordingly.
※ Special tool
Pry bar 5870 345 065 73073TM035

3-83
② Demount speed sensor as well as both
inductive transmitters (arrows).

73073TM036

③ Loosen hexagon nuts and remove the

two covers (arrows).
Loosen screw connection.

73073TM037

④ Drive both cylindrical pins (arrows) out.

73073TM038

⑤ Separate housing cover carefully from

gearbox housing, using lifting device.
※ Special tool
Lifting chain 5870 281 047

73073TM039

3-84
⑥ On the right figure shows the installation
position of the single clutches as well as
of the input and output.
KV Forward clutch
KR Reverse clutch
K1 1st speed clutch
K2 2nd speed clutch
K3 3rd speed clutch
K4 4th speed clutch
AN Input
AB Output 73073TM040

※ The following figures describe the

common removal of all clutches.
For this purpose, the housing cover,
combined with special tool is necessary.
The removal of single clutches without
help of the housing cover and the
handles is extremely difficult because of
the installation condition.
Besides, there is the danger of injuries.
※ Prior to the common removal of the
clutches, the output shaft must be
removed, see the below figure.

⑦ Loosen socket head screws and remove

output shaft as well as both oil baffle
plates.

73073TM042

3-85
⑧ Assemble housing cover carefully until
contact is obtained.
Fix all clutches in the housing cover,
using handles.
※ Special tool
Handle (6EA needed) 5870 260 010

73073TM201

⑨ Separate housing cover along with

clutches from gearbox housing, using
lifting device.
※ Special tool
Handle (6EA needed) 5870 260 010

73073TM200

⑩ Fasten housing cover on assembly car.

73073TM045

⑪ Tilt housing cover 180˚.

Remove handles.
※ Special tool
Handle (6EA needed) 5870 260 010

73073TM046

3-86
⑫ Remove K2 clutch.

73073TM047

⑬ Remove K1 clutch, at the same time, lift

K4 clutch.

73073TM048

⑭ Lift K3 clutch out of the housing cover.

73073TM049

⑮ Remove K4 clutch, at the same time lift

input slightly.

73073TM050

3-87
16 Separate KV and KR clutches together
with input from the housing cover.

73073TM051

17 Remove bearing outer race and pull

output shaft (power take-off) out of the
housing bore.

73073TM180

18 Squeeze rectangular ring (arrow) out and

separate ball bearing from shaft.

73073TM179

※ If contrary to the recommendation, the

tapered roller bearings of the clutches as
well as of the input and output would not
be renewed, the allocation of the inner
and outer races to the single assemblies
must at least be maintained.
※ Mark bearing inner and outer races
accordingly.

3-88
(8) Disassemble KV and KR clutch
※ The following figures show the
disassembly of the KV clutch.
The disassembly of the KR clutch is
analogous.
① Squeeze rectangular ring (arrow) out.

73073TM54

② Pull tapered roller bearing from the shaft.

Demount opposite tapered roller bearing
accordingly.
※ Special tool
Grab sleeve 5873 001 057
Basic set 5873 001 000

73073TM55

③ Separate plate carrier from shaft.

※ Special tool
Hammer 5870 280 004

73073TM56

④ Squeeze snap ring out and remove plate

pack.

73073TM57

3-89
⑤ Preload compression spring, squeeze
circlip out and remove components.
※ Special tool
Assembly aid 5870 345 086
Set of external pliers 5870 900 015

73073TM58

⑥ Lift piston by means of compressed air

out of the cylinder bore and remove it.

73073TM59

⑦ Remove both O-rings.

73073TM60

⑧ Squeeze inner circlip(Shaft) out.

※ Special tool
Set of external pliers 5870 900 015

73073TM61

3-90
 ⑨ Locate idler gear by means of separating
device (see on the right figure) and press
it from the shaft (see on the below figure).
Remove released needle bearing.
※ Special tool
Separating device 5870 300 028

73073TM62

73073TM63

⑩ Squeeze circlip out and remove ball

bearing.
※ The disassembly of the KR clutch has to
be carried out accordingly.
※ Special tool
Set of internal pliers 5870 900 013

73073TM64

(9) Disassemble K1, K2 and K3 clutch

※ T h e fo l l o w i n g F i g u r e s s h o w t h e
disassembly of the K3 clutch.
The disassembly of the K1 and K2
clutches is analogous.
① Squeeze rectangular ring (arrow) out.

73073TM65

3-91
② Pull tapered roller bearing from the shaft.
Remove opposite tapered roller bearing
accordingly, see Figure ① , ②.
※ Special tool
Grab sleeve 5873 001 057
Grab sleeve 5873 001 058
(K3 on output side)
Basic set 5873 001 000

73073TM66

③ Remove running disk, axial needle cage

and axial washer.

73073TM67

④ Remove idler gear.

73073TM68

⑤ Remove both needle bearings as well as

axial bearing.

73073TM69

3-92
⑥ Squeeze snap ring out and remove plate
pack.

73073TM70

⑦ Preload compression spring, squeeze

circlip out and remove components.
※ Special tool
Assembly aid (K2 and K3) 5870 345 085
Assembly aid (K1) 5870 345 086
Set of external pliers 5870 900 015

73073TM71

⑧ Press piston out of the plate carrier,

using compressed air.

73073TM72

⑨ Pry plate carrier from the shaft.

※ Special tool
Pry bar 5870 345 065

73073TM73

3-93
(10) Disassemble K4 clutch
① Squeeze rectangular ring out and pull
tapered roller bearing from the shaft.
Remove opposite tapered roller bearing
accordingly.
※ Special tool
Grab sleeve 5873 001 057
Basic set 5873 001 000

73073TM74

② Squeeze circlip out and separate plate

carrier from the shaft.
※ Special tool
Assembly aid 5870 345 085
Set of external pliers 5870 900 015

73073TM75

③ Squeeze snap ring out and demount

plate pack.

73073TM76

④ Preload compression spring, squeeze

circlip out and remove components.
Demount piston.
※ The separation of shaft and gear is not
possible (shrink fit).
※ Special tool
Assembly aid 5870 345 085

73073TM77

3-94
(11) Disassemble input shaft
① If necessary, press turbine shaft out of
the input shaft.
※ The turbine shaft is axially fixed by
means of a snap ring which will be
destroyed at the pressing out.

73073TM78

② Squeeze rectangular ring out and pull off

the tapered roller bearing.
Pull off the opposite tapered roller
bearing.
※ The separation of input shaft 1 and gear
2 is not possible (shrink fit).
※ Special tool
Grab sleeve 5873 001 058
Basic set 5873 001 000

73073TM79

3-95
2) ASSEMBLY
※ If contrary to the recommendation, the
tapered roller bearings of the clutches as
well as of the input and output would not
be renewed, the allocation of the inner
and outer races to the single assemblies
must at least be maintained.
(1) Mount oil pipes
※ To ensure the correct assembly of the oil
pipes, the use of the specified special tool
is imperative. 73073TM090

① Install studs (arrows).

·Torque limit : 0.92 kgf·m (6.64 lbf·ft)
※ Insert studs with Loctite.

② Place distance tubes over the studs.

73073TM091

③ Insert suction tube 1, pressure pipe 2

and pressure pipe lubrication 3 into the
housing bores.
Fasten suction tube 1 and pressure pipes
2 provisionally by means of socket head
screw and hexagon nuts.
·Torque limit : 2.35 kgf·m (17.0 lbf·ft)

73073TM092

3-96
④ Locate both pressure pipes by means of
special device.
※ Special tool
Tension bar 5870 654 030

73073TM093

⑤ Tilt housing 180˚.

Roll in suction tubes as well as pressure
pipes (arrows) into the housing bores,
using special tool.
※ Pipe end of pressure pipes (arrows) must
be slightly below the housing plane face,
if necessary equalize.
※ Special tool
Rolling tool 5870 600 003
Rolling tool 5870 600 004 73073TM094
Rolling tool 5870 600 005
Rolling tool 5870 600 006

⑤ Tilt housing 180。.

Check installation position of the two
pressure pipes and correct if necessary.
※ Pipes must be located in the special
device without play and pressure.
Now, remove special device.
※ Special tool
Tension bar 5870 654 030

73073TM095

⑥ Equip screw plug with new O-ring and

install it.
·Torque limit : 5.2 kgf·m (37.6 lbf·ft)

73073TM096

3-97
⑦ Insert all bearing outer races into the
housing bore.
※ In the case that already run bearings are
reused, pay attention to the allocation of
the bearing outer races.

※ Pay attention to the corresponding

markings.

73073TM097

⑧ Insert both oil pipes (arrows) into the

housing cover, tilt housing cover 180。
and roll in oil pipes into the housing
bores.
※ The pipe end must be situated slightly
below the housing plane face.
※ Special tool
Rolling tool 5870 600 005

73073TM098

⑨ Install studs (M8×25, 27EA) according

to the figure on the right.
·Torque limit : 0.92 kgf·m (6.64 lbf·ft)

73073TM099

⑩ Insert set screws (2EA) into the housing

bores (arrows).

73073TM099A

3-98
 Assemble
ssemble KV and KR clutch
The following figures describe the
assembly of the KV clutch.
Pre-assemble plate carrier (Figure ⑪~⑭)
⑪ Check function of the drain valve.
※ Ball may not seize, if necessary clean by
means if compressed air.
Insert both O-rings (arrows) scroll free
into the recesses of the piston and oil
them. 73073TM100

⑫ Assemble piston until contact is obtained.

※ Pay attention to the installation position,
see on the right figure.

73073TM101

⑬ Introduce compression spring along with

spring cup (2EA).

73073TM102

⑭ Preload compression spring and fix it by

means of circlip.
※ Special tool
Assembly aid 5870 345 086

73073TM103

3-99
 KV, KR plate pack
※ The plate equipment, respectively
stacking of KV and KR clutch is identical.
The following draft shows the installation +0.2
2.5 mm
position of the components.
1 Plate carrier 1 3 5 3 6
2 Piston
3 Outer plate-one-sided coated
4 Inner plates
5 Outer plates-coated on both sides
6 Snap ring(Optional s = 2.1~4.2 mm)
7 End shim
※ Install outer plate 3 with the uncoated
side facing the piston, respectively the 4
end shim. 2 7
Install on the end shim side two outer
and inner plates each.
·Effective number of friction surfaces =18.
73033TM13

⑮ Adjust plate clearance = 2.5+0.2 mm.

※ For the adjustment of the plate clearance
there are snap rings of different thickness
available.
To ensure a faultless measuring result,
install plates for the moment without oil.
※ Introduce plate pack according to the
upper draft.

73073TM105

3-100
16 Mount end shim and squeeze snap ring
(e.g. s = 3.0 mm) in.

73073TM106

17Press end shim on with about 10kg and

measure DimensionⅠfrom the end face/
plate carrier to the end shim.
Dimension Ⅰ e.g. 7.25 mm
※ Special tool
Digital-Depth gauge 5870 200 072

73073TM107

18Press end shim against snap ring

(upward) until contact is obtained and
determine Dimension Ⅱ.
Dimension Ⅱ e.g. 4.75 mm
※ Special tool
Digital-Depth gauge 5870 200 072

73073TM108

EXAMPLE
Dimension Ⅰ 7.25 mm
Dimension Ⅱ - 4.75 mm
Difference = Plate clearance = 2.50 mm
※ In case of deviations from the required
plate clearance, correct by means of
corresponding snap ring (s = 2.1~4.2
mm).
Now, remove plate pack, oil and install it
again.

3-101
19Introduce idler gear until all inner plates
are accommodated.
※ This step makes the later assembling of
the idler gear easier.
Now, remove idler gear again.

73073TM109

20 Install stud (arrow).

※ Use Loctite.
·Torque limit : 1.73 kgf·m (12.5 lbf·ft)

73073TM110

21 Inser t ball bearing until contact is

obtained and fix it by means of circlip.

73073TM111

22 Assemble needle bearing.

73073TM112

3-102
23Press idler gear against shoulder.
※ Support it on the bearing inner race.

73073TM113

24 Fix idler gear axially by means of circlip.

※ At KR clutch there is no recess in the
shaft-assemble circlip until contact on the
bearing inner race is obtained.
※ Special tool
Set of internal pliers 5870 900 013

73073TM114

25Assemble pre-assembled plate carrier

until contact is obtained.
※ Only if the plate carrier plane face is
overlapping with the shaft collar, the
accommodation of all inner plates is
ensured, see on the below figure.

73073TM115

73073TM116

3-103
 26 Press tapered roller bearing against
shoulder.
Install opposite tapered roller bearing.

73073TM117

27Check function of clutch by means of

compressed air.
※ At correctly installed components, the
closing, respectively opening of the
clutch is clearly audible.

73073TM118

(2) Assemble K1, K2 and K3 clutch

※ The following figures describe the
assemble of the K3 clutch.
The assembly of the K1 and K2 clutches
has to be carried out accordingly.
① Install stud (arrow).
※ Use Loctite.
·Torque limit : 1.73 kgf·m (12.5 lbf·ft)

73073TM125

② Assemble plate carrier until contact is

obtained.

73073TM126

3-104
③ Check function of the drain valve.
※ Ball may not seize, if necessary clean by
means of compressed air.
Insert both O-rings (Arrows) scroll free
into the piston recesses and oil them.

73073TM127

④ Introduce piston until contact is obtained.

※ Pay attention to the installation position,
see on the right figure.

73073TM128

⑤ Introduce compression spring along with

spring cup (2EA).

73073TM129

⑥ Preload compression spring and fix it by

means of circlip.
※ Special tool
Assembly aid (K2 and K3) 5870 345 085
Assembly aid (K1) 5870 345 086

73073TM130

3-105
 K1, K2 and K3 plate pack
※ The K1, K2 and K3 plate stacking of
clutches are identical.
The following draft shows the installation 2.1
+0.2
mm
position of the components.
1 Plate carrier 1 3 5 6
2 Piston
3 Outer plate-one-sided coated
4 Inner plates
5 Outer plates-coated on both sides
6 Snap ring (optional s = 2.1~4.2 mm)
7 End shim
※ Install outer plate 3 with the uncoated
side facing the piston. 4
·Effective number of the friction surfaces 2 7
= 14.

73033TM15

⑦ Adjust plate clearance = 2.1+0.2 mm :

※ For the plate clearance adjustment there
are snap rings of different thickness
available.
To ensure a faultless measuring result,
install the plates for the moment without
oil.
※ Introduce plate pack according to the
upper draft.
73073TM135

⑧ Fit end shim and squeeze snap ring (e.g.

3.0 mm) in.

73073TM136

3-106
⑨ Press end shim on with about 10 kg, and
measure DimensionⅠfrom the end face/
plate carrier to the end shim.
DimensionⅠ e.g. 8.20 mm
※ Special tool
Digital-Depth gauge 5870 200 072

73073TM137

⑩ Press end shim against snap

ring(Upward) until contact is obtained,
and determine DimensionⅡ.
DimensionⅡ e.g. 6.00 mm
※ Special tool
Digital-Depth gauge 5870 200 072

73073TM138

EXAMPLE :
DimensionⅠ e.g. 8.20 mm
DimensionⅡ e.g. - 6.00 mm
Difference = Plate clearance = 2.20 mm
※ In case of deviations from the required
plate clearance, correct by means of
corresponding snap ring (S =2.1~4.2 mm).
※ Now, demount plate pack, oil and install it
again.

⑪ Assemble running disk 1(50×70×4),

axial needle cage 2 and axial washer 3
(50×70×1).
※ Install running disk 1 with the chamfer
facing the axial needle cage.

73073TM139

3-107
⑫ Assemble both needle bearings.

73073TM140

⑬ Introduce idler gear until all inner plates

are accommodated.

73073TM141

⑭ Assemble axial washer 3 (50×70×1),

axial needle cage 2 and running disk 1
(50×70×4).
※ Install running disk 1 with the chamfer
facing the axial needle cage.
※ Only if the running disk is overlapping
with the shaft collar, the accommodation
of all inner plates is ensured.

73073TM142

⑮ Press tapered roller bearing against

shoulder.

73073TM143

3-108
 16 Press tapered roller bearing against
shoulder.

73073TM144

17Check function of the clutch by means of

compressed air.
※ At correctly installed components, the
closing, respectively opening of the
clutch is clearly audible.

73073TM145

(3) Assemble K4 clutch

① Undercool shaft (about -80 ˚C), heat gear
(about +120˚C) and assemble it until
contact is obtained.

73073TM150

② Locate gear axially by means of circlip.

※ Special tool
Set of external pliers 5870 900 015

73073TM151

3-109
③ Install stud (arrow).
※ Use Loctite.
·Torque limit : 1.73 kgf·m (12.5 lbf·ft)

73073TM152

④ Check function of the drain valve.

※ Ball may not seize, if necessary clean by
means of compressed air.
Insert both O-rings (arrows) scroll free
into the piston recesses and oil them.

73073TM153

⑤ Introduce piston until contact is obtained.

※ Pay attention to the installation position,
see on the right figure.

73073TM154

⑥ Install compression spring and spring

cup (2EA), preload and fix by means of
circlip.
※ Special tool
Assembly aid 5870 345 085

73073TM155

3-110
 K4 plate pack
The following draft shows the installation
+0.2

position of the components. 1.2 mm

1 Plate carrier
1 3 5 6
2 Piston
3 Outer plate-one-sided coated
4 Inner plates
5 Outer plates-coated on both sides
6 Snap ring (optional s = 2.1~4.2 mm) 7
7 End shim
※ Install outer plate 3 with the uncoated side
facing the piston. 4
·Effective number of friction surfaces = 2
10.

73033TM16

⑦ Adjust plate clearance = 1.2+0.2 mm :

※ For the plate clearance adjustment there
are snap rings of different thickness
available.
To ensure a faultless measuring result,
install the plates for the moment without
oil.
Introduce plate pack according to the
draft (see the preceding page).
73073TM160

⑧ Fit end shim and squeeze circlip (e.g. s

= 3.0 mm) in.

73073TM161

3-111
⑨ Press end shim on with about 10kg and
measure DimensionⅠfrom the end face/
plate carrier to the end shim.
DimensionⅠ e.g. 7.20 mm
※ Special tool
Digital-Depth gauge 5870 200 072

73073TM162

⑩ Press end shim against snap ring

(Upward) until contact is obtained and
determine Dimension Ⅱ.
Dimension Ⅱ e.g. 6.00 mm
※ Special tool
Digital-Depth gauge 5870 200 072

73073TM163

EXAMPLE
DimensionⅠ e.g. 7.20 mm
DimensionⅡ e.g. - 6.00 mm
Difference = Plate clearance =1.20 mm
※ In case of deviations from the required
plate clearance, correct by means of
corresponding snap ring (s = 2.1~4.2 mm).
⑪ Introduce idler gear until all inner plates
are accommodated.
※ This step makes the later assembling of
the idler gear easier.
Now, remove idler gear again.

73073TM164

3-112
⑫ Assemble both axial washers as well as
needle cage.
※ Upper and lower axial washer have the
same thickness (50×70×1).

73073TM165

⑬ Assemble both needle bearings.

73073TM166

⑭ Assemble idler gear.

73073TM167

⑮ Assemble axial washer 3 (50×70×1)

needle cage 2 and running disk
1(50×70×4).
※ Install running disk 1 with the chamfer
facing the needle cage.

73073TM168

3-113
16 Assemble pre-assembled plate carrier
until all inner plates are accommodated.

73073TM169

17Fix plate carrier axially by means of

circlip.
※ Special tool
Set of external pliers 5870 900 015
Handle 5870 260 010

73073TM170

18 Press tapered roller bearing against

shoulder.
Install opposite tapered roller bearing.

73073TM171

19Check function of the clutch by means of

compressed air.
※ At correctly installed components, the
closing, respectively opening of the
clutch is clearly audible.

73073TM173

3-114
(4) Pre-assemble input shaft
① Undercool the input shaft (about -80˚C),
heat gear (about +120˚C) and assemble
it until contact is obtained.

73073TM174

② Fix gear axially by means of circlip.

73073TM175

③ Squeeze snap ring into the recess of the

turbine shaft.

73073TM176

④ Introduce turbine shaft until the snap ring

snaps into the recess of the input shaft-
turbine shaft is axially fixed.

73073TM177

3-115
⑤ Press both bearing inner races against
shoulder.

73073TM178

⑥ Install ball bearing.

Squeeze rectangular ring(Arrow) in and
hook it in.

73073TM179

⑦ Insert output shaft into the housing bore

until contact is obtained.

73073TM180

3-116
(5) Install pre-assembled output shaft and
clutches
※ The following figures describe the
common installation of all clutches.
For it, the housing cover, combined with
special tool is needed.
The assembly of single clutches without
housing cover and handles is extremely
difficult because of the installation
conditions.
Besides, there is the danger of injury.

① Insert all bearing outer races into the

housing cover until contact is obtained.
※ In the case that already run bearings are
reused, pay attention to the allocation of
the bearing outer races.

73073TM190

② Insert KR clutch, input shaft and KV

clutch together into the housing cover.

73073TM191

③ Install K4 clutch.

73073TM192

3-117
④ Install K3 clutch.

73073TM193

⑤ Position K1 clutch.

73073TM194

⑥ Insert K2 clutch.

73073TM195

⑦ Figure on the right shows the installation

position of the single clutches in the
housing cover.

73073TM196

3-118
⑧ Locate all clutches by means of handles.
※ Special tool
Handle (6EA needed) 5870 260 010

73073TM197

⑨ Squeeze rectangular rings (7 pieces, see

Arrows) in and hook them in.
Now, grease rectangular rings and align
them centrically.

73073TM198

⑩ Tilt housing cover 180˚.

Mount eye bolts, see Arrows.
※ Special tool
Eye bolt M20 (2EA) 0636 804 003
Eye bolt M16 (1EA) 0636 804 001
Puller device 5870 000 017

73073TM199

⑪ Install adjusting screws.

Position housing cover by means of lifting
device carefully on the gearbox housing
until contact is obtained, respectively
position the clutches in the gearbox
housing.
※ Pay attention to the overlapping of the oil
pipes with the bores in the housing cover.
※ Special tool
Lifting chain 5870 281 047 73073TM200
Adjusting screws 5870 204 007

3-119
 ⑫ Remove handles again.
※ Special tool
Lifting chain 5870 281 047

73073TM201

⑬ Separate housing cover from gearbox

housing, using lifting device.
※ Special tool
Lifting chain 5870 281 047

73073TM202

(6) Output
① Assemble sheet and press both bearing
inner races against shoulder until contact
is obtained.

73073TM203

② Insert bearing outer race (arrow) into the

housing bore until contact is obtained.

73073TM204

3-120
③ Position screening plate.

73073TM205

④ Insert output shaft.

73073TM206

⑤ Fasten both sheets by means of socket

head screws (4EA).
※ Insert socket head screws with Loctite.
·Torque limit : 2.35 kgf·m (17.0 lbf·ft)

73073TM207

⑥ Squeeze rectangular rings (6EA) into the

recesses of the clutch shafts and hook
them in.
Now, grease rectangular rings and align
them centrically.

73073TM208

3-121
⑦ Insert both O-rings (arrows) into the
annular groove of the oil pipes and
grease them.

73073TM209

⑧ Cover mounting face with sealing

compound Loctite.
Install adjusting screws (S) and position
housing cover carefully against gearbox
housing until contact is obtained, using
lifting device.
※ Pay attention to the overlapping of the oil
pipe with the bores in the housing cover.
※ Special tool
Adjusting screws 5870 204 007 73073TM210
Lifting chain 5870 281 047

⑨ Install both cylindrical pins.

73073TM211

⑩ Fasten housing cover by means of

hexagon head screws.
·Torque limit : 4.69 kgf·m (33.9 lbf·ft)
※ Pay attention to the position of the fixing
plate, see Arrow.

73073TM212

3-122
 ⑪ Install shaft seal, with the sealing lip
facing the oil chamber.
※ By application of the prescribed driver,
the exact installation position is obtained.
Wet rubber-coated outer diameter with
spirit.
Grease sealing lip.
※ Special tool
Driver 5870 048 057
73073TM213

⑫ Heat the output flange (maximum 90˚C),

assemble it and fix it by means of washer
and hexagon head screws.
※ Wet contact area of washer with sealing
compound Loctite.
·Torque limit : 3.47 kgf·m (25.1 lbf·ft)

73073TM214

⑬ Fix hexagon head screws by means of

lock plate.
Install output flange on the converter side
accordingly (figure ⑪~⑬).
※ Special tool
Driver 5870 057 011
Handle 5870 260 002

73073TM215

(7) Converter pressure valve

① The illustration on the right shows the
components of the converter pressure
valve.
1 Piston
2 Compression spring
3 Valve insert
4 Roll pin

73073TM220

3-123
 ② Introduce compression spring and
piston, preload and fix them by means of
※ roll pin.
Special tool
Assembly aid 5870 345
084

73073TM221

③ Insert pre-assembled converter pressure

valve into the housing bore.

73073TM222

(8) Oil feed housing-Transmission pump

① Install two adjusting screws (arrows) and
mount flat gasket.
※ Special tool
Adjusting screws 5870 204 011

73073TM223

② Mount oil feed housing and fix it

provisionally by means of washers and
hexagon head screws.
※ Screw the hexagon head screws in only
until contact is obtained-do not tighten.

73073TM224

3-124
③ Install two adjusting screws and
introduce stator shaft until contact is
obtained.
※ Pay attention to the overlapping of the
bores.
※ Special tool
Adjusting screws 5870 204 007

73073TM225

④ Install O-ring (arrow) and oil it.

73073TM226

⑤ Introduce transmission pump until

contact is obtained.
※ Pay attention to the overlapping of the
bores.

73073TM227

⑥ Equip socket head screws with new

O-rings (arrow).
※ Grease O-rings.

73073TM228

3-125
⑦ Fasten transmission pump by means of
socket head screws.
·Torque limit : 4.69 kgf·m (33.9 lbf·ft)

73073TM229

⑧ Fix oil feed housing finally by means of

hexagon head screws (mount flat
washers).
·Torque limit : 2.55 kgf·m (18.4 lbf·ft)
※ Pay attention to the installation position of
the fixing plate (arrow), see the next
figure.

73073TM230

73073TM231

⑨ Fit flat gasket and fasten cover by means

of hexagon head screws.
·Torque limit : 2.35 kgf·m (17.0 lbf·ft)

73073TM232

3-126
(9) Engine connection-Converter
① Fasten converter housing by means of
hexagon head screws.
·Torque limit : 6.93 kgf·m (50.2 lbf·ft)

73073TM233

② Fasten input shaft, membrane and disk

by means of hexagon head screws.
·Torque limit : 11.7 kgf·m (84.8 lbf·ft)

73073TM234

③ Fasten membrane on the converter,

using hexagon head screws(Mount flat
washers).
·Torque limit : 11.7 kgf·m (84.8 lbf·ft)
※ Insert hexagon head screws with Loctite.

73073TM235

④ Introduce converter until contact is

obtained.
※ Impulse disk of the converter must be
centrally to the bore of the inductive
transmitter, see on the below figure.
Only in this way it is ensured that the
c o n ve r t e r h a s b e e n c o m p l e t e l y
introduced.

73073TM236

3-127
 73073TM237

⑤ Inser t ball bearing until contact is

obtained and fix it by means of circlip.
※ Special tool
Set of internal pliers 5870 900 013

73073TM238

⑥ Assemble housing cover.

Install input flange, fit disk and pull cover
by means of hexagon head screws
evenly against shoulder.
※ Pay attention to the radial installation
position of the cover.

73073TM239

⑦ Fasten cover by means of hexagon head

screws and nuts on the conver ter
housing.
·Torque limit : 4.69 kgf·m (33.9 lbf·ft)

73073TM240

3-128
 ⑧ Fasten input flange finally and fix
hexagon head screws by means of lock
plate.
·Torque limit : 3.47 kgf·m (25.1 lbf·ft)
※ Special tool
Driver 5870 057 010
Handle 5870 260 002

73073TM241

(10) Converter safety valve

① The illustration on the right shows the
components of the converter safety
valve.
1 Plate
2 Ball
3 Compression spring
4 Valve insert
5 Valve sleeve
6 Cylindrical pin 73073TM245

② Assemble components according to

figure ①, preload and fix by means of
cylindrical pin.
※ Special tool
Assembly aid 5870 345 084

73073TM246

③ Insert converter safety valve into the

housing bore until contact is obtained.

73073TM247

3-129
(11) Fit duct plate
① Install both screw plugs (arrows),
※ Install new sealing rings.

73073TM248

② Install gasket, place duct plate against

shoulder and fasten it by means of
socket head screws and hexagon nuts
(mount flat washers).
·Torque limit : 2.55 kgf·m (18.4 lbf·ft)

73073TM249

(12) Fit hydraulic control unit

① Install two adjusting screws.
Mount gasket 1, intermediate plate 2 and
gasket 3.
※ Pay attention to the installation position of
the different gaskets, see also the
following draft.
※ Special tool
Adjusting screws 5870 204 031
73073TM250

3
2
1

3-135(4) (740-7)

3-130
 ② Fasten complete control unit on the duct
plate, using socket head screws.
·Torque limit : 0.97 kgf·m (7.01 lbf·ft)

73073TM251

(13) Filter
① The illustration on the right shows the
components of the filter unit.
※ Install new O-rings (arrows)

73073TM252

② Fasten intermediate plate and filter head

by means of hexagon head screws
(mount flat washers).
·Torque limit : 2.55 kgf·m (18.4 lbf·ft)

73073TM253

③ Oil gasket and tighten exchange filter

hand-tight.

73073TM254

3-131
④ If necessary, install warning switch
(according to the version).

73073TM255

⑤ Insert O-ring (arrow) into the annular

groove of the oil feed covers.

73073TM256

⑥ Fasten the two covers (arrows) by means

of hexagon nuts (mount flat washers) on
the housing.
·Torque limit : 2.55 kgf·m (18.4 lbf·ft)

73073TM257

⑦ Mount oil level tube.

Install screw plug (arrow).
※ Install new gaskets.
·Torque limit : 2.35 kgf·m (17.0 lbf·ft)
·Torque limit (screw plug M26×1.5) :
8.16 kgf·m (59.0 lbf·ft)

73073TM258

3-132
(14) Speed sensor and inductive transmitter
① Grease O-ring, introduce speed sensor
(arrow) and fasten it by means of socket
head screw.
·Torque limit : 2.35 kgf·m (17.0 lbf·ft)
34 Speed-output and -speedometer

73073TM259

② Equip the inductive transmitters with new

O-rings and install them.
·Torque limit : 3.06 kgf·m (22.1 lbf·ft)
48 Speed-engine
47 Speed-central gear train
21 Speed-turbine
Install breather (arrow).

73073TM260

③ Install gasket and cover plate, arrow 1.

·Torque limit : 2.35 kgf·m (17.0 lbf·ft)
Equip screw plug (arrow 2) with new
O-ring and install it.
·Torque limit : 14.3 kgf·m (103.3 lbf·ft)

73073TM261

3-133
3. AXLE
1) SERVICE BRAKE DISASSEMBLY

7
1 8

3
44
2

5
6
9
10
11
12
12
13
13

14
7409RAX001

(1) Sling the arm to be removed and connect

it to a hoist.
Loosen and remove screws.

7409RAX002

(2) Note down their order of assembly and

remove the counterwasher (1). 1

7409RAX003

3-134
 Down Side

7409RAX004

7409RAX005

(3) Remove braking discs (2)(3), noting down

direction of assembly.
※ If disks are not to be replaced, avoid 2
changing their position.

7409RAX006

(4) Remove the flange (4) complete with the

discs.

4
7409RAX007

3-135
(5) Noting down direction of assembly.

7409RAX008

(6) Remove braking discs, noting down

direction of assembly.
※ If disks are not to be replaced, avoid
changing their position.

7409RAX009

(7) Remove the reversal springs (7)

7409RAX010

reversal springs
7409RAX011

3-136
(8) Remove the adjusting screws (5)
5

7409RAX012

adjusting screws
7409RAX013

(9) S l o w l y i n t r o d u c e l o w - p r e s s u r e
compressed air through the connection
member for the service brake (P1), in 9
order to extract the piston (9).
※ Hold the piston (9) back, as it may be
suddenly ejected and damaged.

7409RAX014

P1 = service brake

7409RAX015

3-137
2) SERVICE BRAKE ASSEMBLING

1.02~1.53 kgf·m
Loctite 242

0.51~0.71 kgf·m
Loctite 242

7409RAX016

(1) Insert the stroke automatic regulation

springs (6); place them in line with the 6
piston (9).

7409RAX017

(2) Fit O-ring (11)(12) and back-up ring (10)

(13) onto the piston (11).
Lubricate the piston and the O-rings and
install the unit into the arm (14).

7409RAX018

3-138
(3) Using a plastic hammer, ram the piston
(9) into the arm (14).
9
※ Lightly hammer all around the edge in an
alternate sequence.

14
7409RAX019

(4) Fit the reversal springs (7) on the piston

(9).
Apply loctite 242 to the thread of the
adjustment screw.
Tighten with torque wrench setting of
0.51~0.71 kgf·m (3.69~5.14 lbf·ft).

7409RAX020

(5) Fit the adjusting screws (5).

Apply loctite 270 to the thread.
·Torque wrench setting :
0.51~0.71 kgf·m (3.69~5.14 lbf·ft)

7409RAX021

reversal spring

adjusting screws
7409RAX022

3-139
(6) Inser t the brake discs in the right First disc
sequence.
※ The first brake disc (2) to be inserted must
be of metal material.

2
7409RAX023

※ The second brake disc (3) to be inserted Second disc

must be of friction material.

7409RAX024

Metallic disc
Clutch disc

Differential side Arm side

※ Number of discs can change.

7409RAX025

3-140
(7) Install the flange (4) on the arm.

7409RAX026

(8) Insert the brake discs (2)(3) in the right Last disc
sequence.
※ The last brake disc to be inserted must be
of friction material.

2 3
7409RAX027

(9) Insert the intermediate disk (1).

1
7409RAX028

7409RAX029

3-141
(10) Check integrity and position of the
cylinder’s O-ring.

7409RAX030

(11) Cross tighten the nuts in two stages.

·Torque wrench setting :
20.4~22.5 kgf·m (148~163 lbf·ft)

7409RAX031

3-142
 3) HOW TO DISASSEMBLE THE PLANETARY REDUCTION

2
3
21

1 4

5
6
20
19 9
18 17 7
16
8 10
14
11
15
24

12
26
13
22

23
29

25 28

27 30
31
7409RAX032

(1) Remove oil-level plug (30) and the oil.

30
7409RAX033

(2) Remove the locking screws (31) of

planetary cover (29).

31
29

7409RAX034

3-143
(3) Using two screwdrivers or two levers
inserted in the slots provided, pry the
planetary cover (29) away from the wheel
hub (10).

29
7409RAX035

(4) Remove the cover (29).

29
7409RAX036

(5) Remove the axle half shaft (4).

7409RAX037

(6) Remove the safety spring rings (16) of the

16
planetary gears (14).

14

7409RAX038

3-144
(7) Remove the planetary gears (14).

14

7409RAX039

※ Note down direction of assembly of

planetary gears.

Down

7409RAX040

(8) Check the wear of the shim washer (28) .

28
7409RAX041

(9) Accurately check the O-ring (22).

22

7409RAX042

3-145
(10) Loosen the nuts (27) and remove them.
27

7409RAX043

(11) Remove the safety flange (26).

26
7409RAX044

(12) Using an extractor and applying a counter

pressure to the screws (25), disengage
the crown wheel (23) from the hub (10).

23
7409RAX045

(13) Remove the crown (23).

23

7409RAX046

3-146
(14) With the help of a hammer, shift the hub
(10) and the external bearing (13).

13

10
7409RAX047

(15) Extract the external bearing (13).

13

7409RAX048

(16) Using an extractor and applying a counter

pressure to the screws disengage the hub 10

(10).

7409RAX049

(17) Remove the internal bearing (8) and the

hub (10).
10

7409RAX050

3-147
(18) Remove the seal ring (7) from the hub
(10).
※ Note down direction of assembly.
※ The seal ring may not be reused.
7

10

7409RAX051

(19) Remove the internal bearing (8) and

sealing ring (7).
7

10

7409RAX052

(20) Remove the external thrust blocks of

bearings, using a pindriver.
※ Hammer in an alternate sequence to
prevent crawling and deformation of the
thrust blocks.

7409RAX053

(21) Remove the external thrust blocks of

bearings, using a pindriver.
※ Hammer in an alternate sequence to
prevent crawling and deformation of the
thrust blocks.

7409RAX054

3-148
(22) Using an extractor, remove seal ring (5)
and guide ring(6).
※ Note down the direction of assembly of
snap ring.

7409RAX055

Sealing
Sealing Ring (5)
Ring (5)

Oil Side
Oil Side

Guide
Guide Ring (6)
Ring (6)

7409RAX056

3-149
4) A S S E M B L I N G T H E P L A N E TA RY
REDUCTION

33.7~39.3
330 - 385 Nmkgf·m
Loctite 242
Loctite 242
7409RAX057

(1) Lubricate and fit the seal ring (5) and

guide ring(6) onto tool T3; install the rings
into the arm.

5 T3

Lubricate
7409RAX058

※ Pay particular attention to the direction of

Sealing
Sealing Ring (5)
Ring (5)
assembly of the rings.

Oil Side
Oil Side

Guide Ring
Ring (6)
(6)

7409RAX059

3-150
(2) Position the lower part of tool T1 and the
thrust block of the external bearing (13).

13
T1

7409RAX060

(3) Lubricate the seats of the bearings and

position the hub (10) on tool T1; position
the thrust block of the internal bearing (8).
T1
※ Check that the thrust block is correctly 8
oriented.

10

7409RAX061

(4) Fit the bearing (8) and seal ring (7) into
the internal thrust block.

8 7

7409RAX062

(5) Using special tool apply a repositionable

jointing compound for seals to the outer
surface of the sealing ring (7). Position the
sealing ring (7) in the hub (10).
※ Check that the ring (7) is correctly
oriented.

7409RAX063

3-151
(6) Install the wheel hub.
13

7409RAX064

(7) Install the external bearing (13).

※ Move the bearing to the limit stop by
hammering lightly all around the edge.

13
7409RAX065

(8) Install the crown wheel (23). 23

7409RAX066

(9) Fit the complete crown flange (23).

※ In order to fasten the flange (23), use a
plastic hammer and alternately hammer
on several equidistant points.

23
7409RAX067

3-152
(10) Install the security flange (26).
Using grease the surface of the safety
flange (26) that touches the crown wheel.

7409RAX068

(11) Coat the nuts (27) with loctite 242 and

screw them.
Tighten nuts (27) in two stages, using the 27
criss-cross method.
·Initial torque wrench setting :
33.7 kgf·m (244 lbf·ft)
·Final torque wrench setting :
39.3 kgf·m (284 lbf·ft)

7409RAX069

※ Check the condition and position of the

O-ring (12).
12

7409RAX070

(12) Fit shim washer (28) into spider cover

(29).

28

7409RAX071

3-153
(13) Insert the planet wheel gears (14) into the
cover (29).
16
Lock gears (14) into position by installing
the snap rings.

14

7409RAX072

(14) Accurately check the orientation.

Down

7409RAX073

(15) Fit the planetary carrier cover onto the

hub.
※ Check that the O-ring is in good condition
and in position.

7409RAX074

(16) Lock the planetary carrier cover by

tightening the screws.
·Torque wrench setting for screws :
3.57~5.1 kgf·m (25.8~36.9 lbf·ft)

31

7409RAX075

3-154
 5) HOW TO REMOVE AND DISASSEMBLE THE DIFFERENTIAL UNIT

1 2
3 4

7
8 9
5 10
19
39 6 17 20
18
38
22
12
40 24
13
14
28 29 30 15 21
41
23
27
37
25 26
31

32

33

34
36
35 7409RAX076

(1) Sling the arm to be removed and connect

it to a hoist.
Loosen and remove screws and nuts.

7409RAX077

(2) Only if need removing or adjusting.

Remove the screw (27).

7409RAX078

3-155
(3) Only if need removing or adjusting. 80˚C
Uniformly heat the ring nuts up to a
temperature of 80˚C.

7409RAX079

(4) Only if need removing or adjusting.

Using special tool T4 mark the position of
the ring nuts (2) (26).
2 26

T4

7409RAX080

(5) Loose he stud bolts (35)(41) and remove

two of them.

7409RAX081

(6) Disjoin the cover (38)(33) crown side.

38 33

7409RAX082

3-156
(7) Remove the cover and studs.

7409RAX083

(8) Extract the whole differential unit.

7409RAX084

(9) Remove the snap ring (30).

13

7409RAX085

(10) Remove the cap (29).

29

7409RAX086

3-157
(11) If the bearings need replacing, extract the 3 25
external thrust blocks of the bearings (3)
and (25) from middle cover (33)(38).
※ Accurately check the O-ring (37)(36).

33 38
O-ring 37 36
7409RAX087

(12) If the bearing need replacing, extract the

bearing (3). 3

7409RAX088

(13) If the bearing need replacing, extract the

bearing (25) from the differential carrier
(23).

25

23

7409RAX089

(14) Remove the fitting screws (4) of the crown

(6).

7409RAX090

3-158
(15) Remove the spacer (42) and the crown
4
(6).

7409RAX091

(16) Remove the screws (24) jointing the

differential unit half box .

24

7409RAX092

(17) Using a plastic hammer, take the half box

(23)(5) to pieces.
※ Note down the coupling marks.

23

7409RAX093

(18) Remove the upper half box (23).

23

7409RAX094

3-159
(19) Remove shoulder (22) and first planetary
gear (21). 22
21

7409RAX095

(20) Remove shafts (18), complete with planet

19 15
wheels (15)(19) and spherical shoulder
washers (14)(20). 18

14 20

7409RAX096

(21) Remove shafts (17), complete with planet

wheels (10)(12) and spherical shoulder 17
washers (9)(13).

10 12
9 13

7409RAX097

(22) Remove the 2nd planetary gear (8) and

shoulder ring (7).
8

7409RAX098

3-160
(23) The differential unit.
Sh = shafts (18)(17)
5
SW = spherical shoulder washers (9)(13)
(14)(20)
P = planetary gears (8)(21) 23

SR = shoulder ring (22)(7) P

23 = upper half box

SR
5 = half box crown side SH
S = planet wheels (10)(12)(15)(19) S SW
7409RAX099

3-161
6) HOW TO ASSEMBLE AND INSTALL
THE DIFFERENTIAL UNIT

7409RAX100

(1) Install the shoulder ring (7) and planetary

gear (8) into the halfbox (5).

7409RAX101

(2) Install the planetary gears (10)(12) and

spherical shoulder washers (9)(13) onto 17
the shafts (17).
Install the planetary set.
10 12
9 13

7409RAX102

3-162
(3) Install the planetary gears (15)(19) and
spherical shoulder washers (14)(20) onto
the shafts (18). 18
Install the planetary set.
15 19 14 20

7409RAX103

(4) Install the planetary gear (21) and 22

shoulder ring (22).
21

7409RAX104

(5) Mount the locking half-box (5) onto the

23
half-box (23)

7409RAX105

(6) Lock the half box with screws (24) coated Loctite 270
with loctite 270.
※ 1. The match marks on the two half-
boxes must correspond. 24
2. Use only new screws.

7409RAX106

3-163
(7) Fit the complete differential unit in a vice
and tighten the screws (24) holding the
two half boxes together to a torque of 8.16
24
kgf·m (59 lbf·ft).
※ Tighten screws using the alternate and
criss-cross method.

7409RAX107

(8) Install the spacer (4) and the crown (6).

4

7409RAX108

(9) Mount the gear ring (6) and fasten it to the Loctite 270
differential box with screws (4).
※ Use only new screws.

7409RAX109

(10) Lock the gear ring (6) by tightening the

screws (4) to a torque of 15.3 kgf·m (111
lbf·ft).
※ Use the alter nate and criss-cross
tightening method.

7409RAX110

3-164
 Installation of the differential unit
(11) Position the differential unit under a press 100˚
and, using a driver with an adequate
diameter, install the first bearing (3).
3

7409RAX111

(12) Turn the unit upside down and install the

100˚
second bearing (25).
※ Pay particular attention; position a shim
with adequate diameter in order to 25

engage the internal ring of bearing

without engaging the cage.

7409RAX112

(13) Only if bearings are replaced.

Insert the thrust blocks of the bearings
into the intermediate covers.

7409RAX113

※ Thoroughly check the state of the O-ring

(36)(37).

36 37

7409RAX114

3-165
(14) Fit the intermediate cover (33) on
opposite side of ring gears : 35
lock cover with screws (35) coated with
loctite 242.
Tighten screws to a torque of 14.3 kgf·m
(103 lbf·ft). 28

33
7409RAX115

(15) Position the differential unit in the central

body with the help of a bar and fit the
middle cover.

7409RAX116

(16) Tighten the two safety screws “C” into the

main body (28) and install the 28
intermediate cover (38).

38

7409RAX117

(17) Tighten screws to a torque of 14.3 kgf·m

(103 lbf·ft).

7409RAX118

3-166
(18) Only if ring nuts have been removed. 1/4 turn
Tighten the ring nut (2) on gear ring side
until clearances between pinion and gear
ring are zeroed. Then, loosen by about
1/4 turn.

T4
2
7409RAX119

(19) Only if ring nuts have been removed.

Preload bearings with ring nut (26) on
non-gear ring side in order to increase the
torque of the pinion.
※ In the case of used bearings, check thrust
torque ; in the case of new bearings,
check continuous torque. T4

26
7409RAX120

(20) Apply torque meter TM to pinion nut and

check that torque will increase by
2 . 0 4 ~ 4 . 0 8 kgf·cm a s a r e s u l t o f
differential bearing preload.
·Example : pinion torque : TM
12.2~13.3 kgf·cm
·Pinion + differential torque :
14.3~17.3 kgf·cm

7409RAX121

(21) Introduce a comparator “A” with long

tracer through the hole provided for the
cap.
Position the tracer on the side of a tooth
of the gear ring, approximately 5 mm from
the outer rim; preload by about 1 mm and
zero the comparator.

A
7409RAX122

3-167
(22) As you hold the pinion in position, move Gap = 0.25 - 0.33 mm
the gear ring manually in both directions
to check clearance between pinion and
gear ring.
Standard clearance : 0.25 - 0.33 mm

7409RAX123

(23) If torque and/or pinion-gear ring clearance

is not within tolerance values and the ring
nuts have not been removed, mark the
position of the ring nuts (2)(26) and
remove the safety stops (1)(27).
1 27

2 26

7409RAX124

(24) Adjusting clearance between pinion and

gear ring.
To INCREASE: loosen the ring nut on
gear ring side and tighten the ring nut on
non-gear ring side by the same measure.
To DECREASE: perform the same
operations inversely.
To rotate ring nuts, use special wrench T4. T4

7409RAX125

(25) Engage screw (27) in the slot next to the

holes provided for the check screws.
Coat screws (27) with loctite 242 and
tighten to a torque of 2.45~2.65 kgf·m
(17.7~19.2 lbf·ft).

7409RAX126

3-168
(26) F i t t h e t o p p l u g a f t e r a p p l y i n g
repositionable jointing compound for seals
to the rims.
Install the snap ring.

7409RAX127

(27) Install the complete arm.

7409RAX128

(28) Torque wrench setting :

28.9~31.8 kgf·m (209~230 lbf·ft)
※ Tighten using the criss-cross method.

7409RAX129

3-169
7) DISASSEMBLY OF THE PINION

3
6
2
14
15
7
1
8
13

10 16
11

12

7409RAX130

(1) Remove both axle arms.

7409RAX131

(2) If disassembly is awkward, heat the check

nut (1) of the flange (10) at 80˚C.
※ Heating is meant to unloose the setting of 1
loctite on the nut (1). 10

7409RAX132

3-170
(3) Position tool T12, so as to avoid pinion
rotation.
Unloose and remove the nut (1); also
remove the O-ring (11).

T12

7409RAX133

10
11 10

7409RAX134

(4) Remove the flange (10) complete with

guard (2).

10

7409RAX135

(5) Remove the sealing ring (9).

9
7409RAX136

3-171
(6) Apply blocks T15 and, with the help of a
puller, extract the pinion (5) complete with
the internal bearing (6), the distance piece T15
(8) and shims (4)(7).
※ The thrust blocks of the bearings remain
in the central body (12).

12
5

7409RAX137

(7) Refer and keep to the positions marked

during disassembly.
7

8
4

6 5

7409RAX138

(8) Using a puller and a press, remove the

inner bearing (5) from the pinion (6).

7409RAX139

(9) Remove the thrust block of the external

bearing (3).
3

7409RAX140

3-172
(10) Insert a drift in the appropriate holes.

7409RAX141

(11) Remove the thrust block of the internal

6
bearing (6) as well as the shim washers
(4).
4

7409RAX142

(12) Remove the snap ring (15).

15

7409RAX143

(13) Remove the cap (14).

14

7409RAX144

3-173
8) ASSEMBLY OF THE PINION

D
I = 135 mm

S1

I = 178 mm S

S = 178 - ( I + D ) S = shims Ø 110 mm

S1 = shims Ø 50 mm
7409RAX145

Calculating pinion center distance

(1) Using a faceplate, reset a centesimal
comparator “DG” on a calibrated block
(whose known thickness is 42 mm).
Preload the comparator by about 3 mm.

42 mm

7409RAX146

(2) Bring inner bearing (6), complete with

thrust block, under comparator "DG".
※ Press the thrust block centrally and carry
out several measurements by rotating the
thrust block.
Example : 42 + 0.5 = 42.5 = "D".

7409RAX147

3-174
(3) Check nominal dimension “I” as marked
on the pinion. Add up to or subtract from
“I” the variation indicated as “Y” to obtain
the actual center distance “I”.
1 = 135
Example : I = 135 - 0.1 = 134.9
※ M5 = Match part number M5

-0.1=Y

7409RAX148

(4) Calculate shims “S” for insertion under the

thrust block of the inner bearing using the
following formula :
S = 178 - (I + D) where : 178 = fixed
dimension
I = actual pinion center distance
D = total bearing thickness ;
Example :
S = 178 - (134.9 + 42.5) = 0.6 mm.
7409RAX149

(5) Using special tool T10.

Partially insert the thrust block of the
bearings (3) (6) and shims (4) .

6
4
3
T10

7409RAX150

(6) Connect the tension rod to the press and

move the thrust block of bearings (3) (6)
into the seats.
Disconnect the press and remove the
tension rod.
※ Before starting the next stage, make sure
that the thrust block has been completely
inserted into its seat.

7409RAX151

3-175
 Calculating pinion bearings rolling
torque
12
(7) Introduce tool T11 complete with bearings
(3) and (6) into the main body (12); tighten 6 3
by hand until a rolling torque is definitely
obtained.

T11

7409RAX152

(8) Introduce the tracer of a depth comparator

“DDG” into either side hole of tool T11.
Reset the comparator with a preload of
about 3 mm. A
DDG
A

T11
T11
7409RAX153

(9) Remove the comparator and take out tool

and bearing kits from the main body.
Reinstall every part, also introducing a 6
3
distance piece between bearings (3) and
(6). Tighten the entire pack by hand.

7409RAX154

(10) Introduce depth comparator “DDG” in tool

T11 and measure deviation “H” from the B
previous reset.
B
Example : H = A - B = 1.19 mm.

T11

7409RAX155

3-176
(11) Deviation “H” must be added to a set
value of 0.12~0.13 mm (X) to make up the
pack of shims “S1” (4) for insertion
between inner bearing (6) and distance
piece (8).
Dimension “S1” must be rounded off to
4
the higher 5/100.
Example : S1=H+X=1.19+(0.12~0.13)
=1.33~1.35 mm.
7409RAX156

(12) Heat the inner bearing (6) to about 100˚C

and fit it to the pinion (5).
※ Once the bearing has cooled down, lightly
lubricate bearing (6) with SAE 85W90 oil. 100˚C
5

7409RAX157

(13) Make sure that the bearing (6) is well set.

6
7409RAX158

(14) Refer and keep to the positions marked

during disassembly.
5
S1 4
3
2 6
1 7
8
9
S1 10
11

7409RAX159

3-177
(15) Fit the pinion (5), shim “S1” (7) and
distance piece (8) in the main body (12).
※ The finer shims must be placed in-
between the thicker ones.

5
12 8

7409RAX160

(16) Heat the external bearing (3) to a

temperature of about 100˚C and fi t it on
to the pinion (5) so as to complete the
pack as shown in the figure.
※ Lightly lubricate bearing (3) with SAE 3
85W90 oil.

7409RAX161

(17) Install the flange (10) onto the pinion (5)

without sealing ring.

5 10

7409RAX162

(18) Apply wrench to the ring nut (1) and bar-

hold T12 to the pinion (5).
Lock the wrench T12 and rotate the pinion
using a dynamometric wrench, up to a
minimum required torque setting of
81.6~102 kgf·m (590~738 lbf·ft)

T12

7409RAX163

3-178
(19) Apply onto the pinion (5) the bar-hold and
with the help of a torque meter, check the
torque of the pinion (5).
·Torque : 12.2~18.4 kgf·cm
※ If torque exceeds the maximum value,
then the size of shim “S1” (7) between the
bearing (6) and the distance piece (8)
needs to be increased.
If torque does not reach the set value,
7409RAX164
increase the torque setting of the ring nut
(1) in different stages to obtain a
maximum value of 81.6~102 kgf·m
(590~738 lbf·ft).
※ If torque does not reach the minimum
value, then the size of shim “S1” (7)
needs to be reduced.
※ When calculating the increase or
decrease in size of shim “S1”, bear in
mind that a variation of shim (4) of 0.01
mm corresponds to a variation of 6.12
kgf·cm in the torque of the pinion (5).

(20) Make positional marks across nut (1) and

pinion (5) tang ; then remove nut and
flange (10)

5
1

10

7409RAX165

(21) Apply Arexons rubber cement to the outer 12

surface of the new seal ring (9) and fit ring
in the main body (12) using driver T13.

9 T13
7409RAX166

3-179
(22) Fit the safety flange (2).

7409RAX167

(23) Oil seal ring lips and install flange (10). Loctite 242
Mount O-ring (11) and apply loctite 242 to
pinion tang; tighten nut (1).

10 11 1
7409RAX168

(24) Tighten the nut until the match marks

made at stage “a” line up.

T12
7409RAX169

3-180
9) D I S A S S E M B L E T H E S W I N G I N G
SUPPORT
Bushing cut positon

4
4

22

3
3

1
1

7409RAX170

(1) Remove the swinging support (3).

3
7409RAX171

(2) Remove the swinging support (3) on the

side opposite the drive.

3
7409RAX172

(3) Position the swinging support (3) under a

press and remove the complete bushing
(4).

7409RAX173

3-181
 4

7409RAX174

(4) Remove the screws.

7409RAX175

(5) Disjoin the cover from the differential box

by alternatively forcing a screwdriver into
the appropriate slots.

7409RAX176

(6) Check integrity and position of the

cylinder’s O-ring.

7409RAX177

3-182
10) ASSEMBLY THE SWINGING SUPPORT

7409RAX178

(1) Install the cover.

7409RAX179

(2) Lock the cover by tightening the screws.

Torque wrench setting for screws :
4.08~5.1 kgf·m (29.5~36.9 lbf·ft)

7409RAX180

※ If the bushing (4) is worn and needs

replacing, note down the assembly side of A
4
the connection notch "A".

reference direction A
7409RAX181

3-183
 Bushing
Bushing cut position
cut positon

reference
direction A

7409RAX182

(3) Position the swinging support (3) under a

press and insert the complete bushing (4).

7409RAX183

(4) Install the swinging support (3). 3

※ Check that it is properly oriented.

7409RAX184

(5) Install the swinging support (4) on the side

opposite the drive.

7409RAX185

3-184
 11) NEGATIVE BRAKE : ASSEMBLING NEGATIVE BRAKE DISKS

1
2
3 6
5
7
4 8
26

9 10
11
25 12
13
24 14
15
23 16

17
18
27 22 21 19

28 20

29
30
31
7409RAX186

Manual emergency release

(1) Loosen nuts (30) of screws (31) provided
for the mechanical and manual release of
the braking units, then move the nuts
backwards by approx. 8 mm.
25
29
26
30
27
31

7409RAX187

(2) Tighten screws (31) so as to fasten them

onto the pressure plate (23).

7409RAX188

3-185
(3) Using a wrench, tighten the screws (31) in
an alternate sequence by 1/4 turn at a
time so as to compress the belleville
washers (1) and disengage the braking
disks.
※ Tighten max. by one turn.

7409RAX189

Adjustment after manual release

(4) Remove screws complete with nuts and
seals.
Replace seals, apply grease to the screws
and install all parts into the arm.

7409RAX190

(5) Adjust screws (31) to obtain a jut of 30 ±

0.5 mm in relation to the arm.

7409RAX191

(6) Lock into position with nuts (30).

※ Hold screws (31) into position while
locking the nuts (30); after locking, check
the jut of screws (31) once more.

7409RAX192

3-186
11) NEGATIVE BRAKE : DISASSEMBLING
(1) Connect an external pump to the union
piece “P1” of the negative brake and
introduce a pressure of 21.4~35.7 kgf/cm2
(304~508 psi) to eliminate the pressure of
the belleville washers (1).

7409RAX193

(2) Sling the arm to be removed and connect

it to a hoist.
Loosen and remove screws (31). 31

7409RAX194

(3) Remove arm together with brakes and

axle shafts; lay down the arm vertically.
Release pressure.

7409RAX195

(4) Remove the reversal springs (13)

13

7409RAX196

3-187
(5) Remove the adjusting screws (21) from
the counterwasher (23). 23

21

7409RAX197

(6) Note down their order of assembly and 23

remove the counterwasher (23).

Down

7409RAX198

(7) Loosen the studs in an alternate manner

and remove them.

7409RAX199

(8) Remove the cylinder (24). 24

7409RAX200

3-188
(9) Remove the centering device (26) in the
cylinder.

26

7409RAX201

(10) Remove the belleville washers (1).

※ Check the sense of direction of washers
(1).
1

7409RAX202

※ The O-rings (2) must be replaced each

time the unit is disassembled.
2

7409RAX203

(11) S l o w l y i n t r o d u c e l o w - p r e s s u r e
compressed air through the connection
member for the service brake (P2), in
order to extract the piston (11).
Service Brake

※ Hold the piston (11) back, as it may be

suddenly ejected and damaged.

7409RAX204

3-189
(12) Note down their order of assembly.

7409RAX205

(13) S l o w l y i n t r o d u c e l o w - p r e s s u r e
compressed air through the connection
member for the service brake (P1), in Down
3
order to extract the piston (3).
※ Hold the piston (3) back, as it may be
suddenly ejected and damaged.

7409RAX206

(14) Remove braking discs (14)(15)(16),

noting down direction of assembly.
※ If disks are not to be replaced, avoid
changing their position.

16
7409RAX207

(15) Remove the flange (17) complete with the

discs (20)(19)(18).

17
7409RAX208

3-190
 14
15
16

17
18
19
20

7409RAX209

(16) Remove distance piece-braking discs (27)

and shims (28), noting down direction of 27
assembly.
※ Build a stack of washers and check the
measure.

28
7409RAX210

3-191
 13) NEGATIVE BRAKE : ASSEMBLING SERVICE BRAKE AND SAHR

7409RAX211

SERVICE BRAKE

7409RAX212

Fix quote = 74.00 mm

Y = brake gap = 0.75 mm - 1.00 mm - 1.25 mm - 1.70 mm
(depending on axle confi guration)
X = intermediate disc distance example = 29.00 mm
V = brake discs pack example = 42.33 mm

S = adjust. shims = 74 mm - (x + y + v) =

example =
74-(29+1.25+42.33)
= 74-72.58
= 1.42 mm = S

7409RAX213

3-192
(1) Complete the O-rings and anti-extrusion
rings on all pistons.
※ The O-rings always have to be assembled
from the pressure facing side.
4
2
25

7409RAX214

(2) Check the position of the anti-extrusion (4)

3
and O-rings (2) (25).
Lubricate the piston and the O-rings and
install the unit (3) into the cylinder (24) .
Down

23
Down

7409RAX215

(3) Using a plastic hammer, ram the piston

(3) into the cylinder (24).
※ Lightly hammer all around the edge in an 3
alternate sequence.

7409RAX216

(4) Fit O-ring (9) and anti-extrusion ring (10)

onto the piston (11). 24 11
Lubricate the piston and the O-rings and
install the unit into the cylinder (24).

7409RAX217

3-193
※ The O-rings always have to be assembled
from the pressure facing side.
11
Out
Out Sid
Side

10
9

7409RAX218

(6) Using a plastic hammer, ram the piston

(11) into the cylinder (24).
11
※ Lightly hammer all around the edge in an
alternate sequence.

24
7409RAX219

(7) Position the belleville washers (1) and

engage the cylinder (24).
※ Check the sense of direction of belleville 24
1
washers (1) and relative centering.

Grease
7409RAX220

(8) Install the centering device (26) in the

cylinder.

26

7409RAX221

3-194
 7409RAX222

(9) Check integrity and position of the

cylinder’s O-ring (2).
2

7409RAX223

(10) Engage the cylinder (24).

※ Check the sense of direction of washers
(1) and relative centering.

Down

24
7409RAX224

(11) Insert the screws and tighten them Loctite 242

alternately.
Lock the cylinder.

7409RAX225

3-195
(12) Tightening the studs with a dynamometric
wrench set to a torque of 3.06~3.57
kgf·m (22.1~25.8 lbf·ft).

7409RAX226

Oil filling

7409RAX227

(13) Connect an external pump to the negative

b ra ke a n d i n t r o d u c e p r e s s u r e t o
21.4~35.7 kgf/cm2 (304~508 psi).

7409RAX228

Negative brake

Service brake

7409RAX229

3-196
(14) Insert the stroke automatic regulation
springs (22); place them in line with the 22
piston (23).

23

7409RAX230

(15) Insert the intermediate disk (23).

23

7409RAX231

(16) Fit the reversal springs (12)(13) on the 12

intermediate disk (23).

13

23

7409RAX232

(17) Apply loctite 242 to the thread of the

adjustment screw.
Tighten with torque wrench setting of
1.02~1.53 kgf·m (7.38~11.1 lbf·ft).

7409RAX233

3-197
(18) Y=brake gap
(0.75 mm 1.00 mm 1.25 mm 1.50 mm)
Y
depending on axle configuration.
Y 21

Y=B
BRAKE
RAKE GAP
7409RAX234

(19) Fit the pin screws.

Apply loctite 270 to the thread.
·Torque wrench setting :
0.51~0.71 kgf·m (3.69~5.16 lbf·ft)

7409RAX235

(20) Take the measure from the surface of the

intermediate disk to the cover sealing X
surface with 30.6 kgf/cm 2 (435 psi) of
pressure introduced.
Example : 29 mm
X

7409RAX236

(21) Put the brake disc pack including the shim 1000 Kg
under a press, load with 1000 kg and take V
the measure "V".
Example : V = 42.33 mm

7409RAX237

3-198
(22) Arm fix quote = 74 mm

74 mm

Arm fix quote = 74 mm

7409RAX238

(23) S = 74 mm - ( x + y + v ) = Thickness of Y = brake gap

shims to insert under the shim washer.
S 28
Example :
74 mm - ( 29 + 42.33 + 1.25) = S = 1.42 mm

S = 74 mm - (x + y + v)
7409RAX239

(24) Insert under the shim washer a thickness

of shims (28).
S 28

7409RAX240

7409RAX241

3-199
 Metallic Disc Clutch Disc

Differential side Armside

Arm side

7409RAX242

(25) Install the friction disc (18) on the flange 18

(17) from arm side.

17

First
First Disc
Disc
18
7409RAX245

7409RAX244

3-200
(26) Install the metal disc (19) on the flange
19
(17) from arm side. 17

2˚ Disc
19
7409RAX243

(27) Install the friction disc (18) on the flange

18 20
from arm side and insert the group on the
19
u-joint.

17 20

3˚ Disc
18

7409RAX246

(28) Insert on the fl ange the discs (16)(15) 16

(14).

4°4˚Disc
Disc
16
7409RAX247

5˚ Disc Last Disc

15 14

7409RAX248

3-201
(29) Check the alignment of last disc (14) and
flange.

7409RAX249

14 15 16 18 19 20

7409RAX250

(30) Apply loctite 242 to the studs and tighten it

using a dynamometric wrench.
·Torque
Torque wrench setting :
3.06~3.57 kgf·m (22.1~25.8 lbf·ft)

7409RAX251

(31) Check integrity and position of the

cylinder’s O-ring.

7409RAX252

3-202
(32) Check integrity and position of the arm’s
O-ring; install the complete arm.
※ To assist axle shaft centering, slightly
move the wheel hub.

7409RAX253

(33) Apply loctite 242 to the nuts and cross

tighten it in two stages.
·Torque wrench setting : 1
20.4~22.5 kgf·m (148~163 lbf·ft)

7409RAX254

3-203
 SECTION 4 BRAKE SYSTEM

Group 1 Structure and Function -------------------------------------------------------------------------------------- 4-1

Group 2 Operational Checks and Troubleshooting -------------------------------------------------------- 4-21
Group 3 Tests and Adjustments -------------------------------------------------------------------------------------- 4-28
Group 4 Disassembly and Assembly ------------------------------------------------------------------------------ 4-31
 SECTION 4 BRAKE SYSTEM
GROUP 1 STRUCTURE AND FUNCTION

1. OUTLINE
※ The brakes are operated by a pressure compensated, closed center hydraulic system.
Flow is supplied by a fixed displacement, gear type brake pump.

BRAKE SYSTEM
The fixed displacement brake pump supplies flow to the cut-off valve for service brake circuit and
park brake circuits. It flows to three accumulator. The accumulator has a gas precharge and an
inlet check valve to maintain a pressurized volume of oil for reserve brake applications.
Oil through the accumulator flows to the brake valves. The brake valve is a closed center design,
dual circuit operated by a pedal.
The front and rear brakes will operate simultaneously with only one brake pedal depressed.
The differential contains annular brake piston and double sided disk.
Main pump flow through the main control valve goes to the parking brake solenoid valve in cut-off
valve.
The brake system contains the following components:
·Brake pump
·Parking brake solenoid valve in cut-off valve
·Cut-off valve
·Brake valve
·Accumulators
·Pressure switches

4-1
FULL POWER HYDRAULIC BRAKE
SYSTEM
ADVANTAGES - The full power hydraulic Response time
brake system has several advantages over Full power brake actuation VS
Air/Hydraulic brake actuation
traditional brake actuation systems. These
systems are capable of supplying fluid to a 1000
range of very small and large volume
service brakes with actuation that is faster 900
than air brake systems. Figure represents 800
a time comparison between a typical air/ Brake pressure
700 (Full power)

Brake torque(lb·in)
hydraulic and full power hydraulic brake
actuation system. 600
Brake pressure
Full power systems can supply significantly 500 (Air/hydraulic)
higher brake pressures with relatively low Brake torque
400
reactive pedal forces. The reactive pedal (Air/hydraulic)
force felt by the operator will be proportional 300
Brake torque
to the brake line pressure being generated. 200 (Full power)
This is referred to as brake pressure
modulation. 100
Another key design feature of full power
0 1 2 3 4
systems is the ability to control maximum
brake line pressure. In addition, because Time(seconds)
these systems operate with hydraulic oil,
filtration can be utilized to provide long
component life and low maintenance
operation.
Because these systems are closed center,
by using a properly sized accumulator,
emergency power-off braking that is
identical to power-on braking can be
achieved. These systems can be either
dedicated, where the brake system pump
supplies only the demands of the brake
system or non-dedicated, where the pump
supplies the demands of the brake system
as well as some secondary down stream
hydraulic device.
Another important note is that all seals
within these system must be compatible
with the fluid medium being used.

4-2
2. HYDRAULIC CIRCUIT

FRONT
39 REAR

18 PS
BL1 BR1 BL2 BR2
8

T1 P1 T2 P2

17 17

7 A1 A2
19
PS

PS

P1

T1
A3
16
B

PS1
PS

19 MCV
P T
Parking Return line
brake solenoid 20
Steering system RCV lever
Fan drive motor
2

23 Return
line

24

25 26

7409S4BS01

2 Fan & brake pump 18 Pressure sensor 25 Return filter

7 Cut off valve 19 Pressure sensor 26 Bypass valve
8 Brake valve 20 Line filter 39 Axle
16 Accumulator 23 Air breather
17 Accumulator 24 Hydraulic tank

4-3
1) SERVICE BRAKE RELEASED

FRONT
39 REAR

18 PS
BL1 BR1 BL2 BR2
8

T1 P1 T2 P2

17 17

7 A1 A2
19
PS

PS

P1

T1
A3
16
B

PS1
PS

19 MCV
P T
Return line
20
Steering system RCV lever
Fan drive motor
2

23 Return
line

24

25 26

7409S4BS02

When the pedal of brake valve (8) is released, the operating force is eliminated by the force of the
spring, and the spool is returned.
When the spool removes up, the drain port is opened and the hydraulic oil in the piston of axles
return to the tank (24).
Therefore, the service brake is kept released.

4-4
2) SERVICE BRAKE OPERATED

FRONT
39 REAR

18 PS
BL1 BR1 BL2 BR2
8

T1 P1 T2 P2

17 17

7 A1 A2
19
PS

PS

P1

T1
A3
16
B

PS1
PS

19 MCV
P T
Return line
20
Steering system RCV lever
Fan drive motor
2

23 Return
line

24

25 26

7409S4BS03

When the pedal of brake valve (8) is depressed, the operating force overcomes the force of the
spring, and is transmitted to the spool. When the spool moves down, the inlet port is opened, and
at the same time the hydraulic oil controlled the pressure level by the cut-off valve (7) enters the
piston in the front and rear axles. Therefore, the service brake is applied.

4-5
3) PARKING BRAKE RELEASED

FRONT
39 REAR

18 PS
BL1 BR1 BL2 BR2
8

T1 P1 T2 P2

17 17 B
A

7 A1 A2
P
19
PS

PS

P1 Parking brake switch

16
T1
A3

B
PS1
PS

19
MCV
P T
Parking Return line
brake solenoid 20
Steering system RCV lever
Fan drive motor
2

23 Return
line

24

25 26

7409S4BS04

When the parking brake switch is pressed A position, the solenoid valve is energized and the
hydraulic oil enters the front axle. It overcomes the force of the spring and pushes the piston rod.
This releases the parking brake.
Therefore, the hydraulic oil pressure is applied to the parking brake piston in front axle through the
solenoid valve and the parking brake is kept released.

4-6
4) PARKING BRAKE OPERATED

FRONT
39 REAR

18 PS
BL1 BR1 BL2 BR2
8

T1 P1 T2 P2

17 17 B
A

7 A1 A2
19 P
PS

PS

P1 Parking brake switch

T1
A3
16
B

PS1
PS

19 MCV
P T
Parking Return line
brake solenoid 20
Steering system RCV lever
Fan drive motor
2

23 Return
line

24

25 26

7409S4BS05

When the parking brake switch is pressed B position, the solenoid valve is deenergized and the
valve open the drain port.
At the same time, the hydraulic oil in the parking brake return to the tank through the solenoid
valve. When the piston rod is returned by the force of the spring, the parking brake is applied.

4-7
3. BRAKE PUMP (+FAN PUMP)
1) STRUCTURE

8
11
12
13
10

Brake pump
10
13
12
11
17
18
19 6

9 2 16
17
16
17
5
7
22 15
21 17
11
12
13
10

3 14

10
Fan pump 13
12
11
4

7309S4BS20

1 Shaft gear 8 Spacer 15 Snap ring

2 Driven gear 9 Rear cover 16 Dowel pin
3 Joint drive gear 10 Bush block 17 D-ring
4 Connector 11 Bushing 18 Bolt
5 Front cover 12 Seal 19 Washer
6 Front housing 13 Back up seal 21 Name plate
7 Rear housing 14 Retainer seal 22 Rivet

This gear pump have a maximum delivery pressure of 150 kgf/cm2.

The pressure loaded type gear pump is designed so that the clearance between the gear and the
bushing can be automatically adjusted according to the delivery pressure. Therefore, the oil leakage
from the bushing is less than that in the case of the fixed bushing type under a high discharge pressure.
Consequently, no significant reduction of the pump delivery occurs, even when the pump is operated
under pressure.

4-8
2) PRINCIPLE OF OPERATION
(1) Mechanism for delivering oil
The drawing at r ight shows the
operational principle of an external gear
pump in which two gears are rotating in
mesh.
The oil entering through the suction port Suction Discharge
is trapped in the space between two gear
teeth, and is delivered to the discharge
port as the gear rotates.
Except for the oil at the bottom of the gear
teeth, the oil trapped between the gear
teeth, is prevented from returning to the
suction side with the gears in mesh.
Since the gears are constantly delivering
oil, the oil delivered to the discharge port
is forced out of the port.
The amount of discharge increases with
the speed of rotation of the gear.
If there is no resistance in the oil passage
into which the discharged oil flows, the oil
merely flows through the passage,
producing no increase in pressure.
If however, the oil passage is blocked with
something like a hydraulic cylinder, there
will be no other place for the oil to flow, so
the oil pressure will rise. But the
pressure which rises in this way will never
go higher, once the hydraulic cylinder
piston starts moving because of the oil
pressure.
As described earlier, the pump produces
the oil flow, but not the oil pressure. We
can therefore conclude that pressure is a
consequence of load.
In other words, the pressure depends on
a counterpart.

(770-3ATM) 4-9

4-9
(2) Internal oil leakage
Oil leaks from a place under higher
pressure to a place under lower pressure,
provided that a gap or a clearance exists
in between.
In the gear pump, small clearances are
provided between the gear and the case
and between the gear and the side plate
to allow the oil to leak out and to serve as
a lubricant so that the pump will be rge
protected from seizure and binding. ischa
D
The drawing at right shows how the
leaked oil flows in the pump. As such,
there is always oil leakage in the pump
from the discharge side (under higher
pressure) to the suction side. The delivery
n
of the pump is reduced by an amount uctio
S
equal to the pump discharge.
In addition, the delivery of the pump will
also decrease as the amount of oil
leakage increases because of expanded
radial clearance resulting from the wear of
pump par ts, the lower oil viscosity
resulting from increases in the oil
temperature, and the initial use of low
(770-3ATM) 4-10
viscosity oil.

4-10
(3) Forces acting on the gear
The gear, whose outer surface is
subjected to oil pressure, receives forces
jointing towards its center.
Due to the action of the delivery pressure,
the oil pressure in higher on the delivery
side of the pump, and due to suction
pressure, is lower on the suction side. In
the intermediate section, the pressure will
gradually lower as the position moves
from the delivery side to the suction side. Drive gear
This phenomenon is shown in the
drawing at right.
In addition, the gears in mesh will receive Suction Discharge
interacting forces. side side
These forces pushing the gears toward
the suction side are received by the
bearings. Since the gears are pressed Driven gear
toward the suction side by these forces,
the radial clearance becomes smaller on
the suction side in the case. In some
pumps, the clearance may become zero, Pressure distribution
thus allowing the gear teeth and the case
to come into light contact.
For this reason, an excessive increase in
the delivery pressure must be avoided,
since it will produce a large force which
will act on the gears, placing an overload
on the bearings, and resulting in a
shortened service life of the bearing or
(770-3ATM) 4-11
interference of the gear with the case.

4-11
4. BRAKE VALVE
1) STRUCTURE

17-2
18
17-3,17-4
17-1,17
19
23 22
24
21
2
33

20 31,32
8,9
25 29

25
16 14
15 7
5 13
30
12 6
10
26
11
3
1 4
7409S4BS07

1 Lower body 13 Spring guide 21 Torsion spring

2 Upper body 14 Snap ring 22 Snap ring
3 Spool 15 Du bushing 23 Hexagon bolt
4 Plug 16 Pedal plate 24 Hexagon nut
5 Holder 17 Pedal assy 25 Bolt
6 Lower spring 17-1 Pedal 26 Spring washer
7 Upper spring 17-2 Lock plate 29 Plate washer
8 Main spring 1 17-3 Hexagon bolt 30 Snap ring
9 Spring retainer 1 17-4 Plate washer 31 Spring retainer 2
10 O-ring 18 Rubber cover 32 Main spring 2
11 O-ring 19 Bellows 33 Taper plug
12 Oil seal 20 Lock pin 1

4-12
2) OPERATION

BL1 BR1 BL2 BR2

T1 P1 T2 P2

Hydraulic circuit

Port Port name Port size

P1, P2 Pressure port PF 3/8
T1
BL1 T1, T2 Return port PF 3/8
P1
BR1, BR2 Brake cylinder port PF 3/8
BR1
BL1, BL2 Pressure switch port PF 1/4
BL2 T2

P2
BR2

7607B4BS08

· Brake pressure specification : 80 ± 5 bar (1160 ± 70 psi)

4-13
(1) Purpose
The purpose of the brake valve is to sensitively increase and decrease the braking pressure
when the brake pedal is actuated.
(2)
2) Ready position
When the braking system is ready for operation, its accumulator pressure acts directly on ports
(P1, P2) of the brake valve. A connection is established between ports (BR1, BR2) and ports (T1,
T2) so that the wheel brakes ports (BR1, BR2) are pressureless via the returns ports (T1, T2).
(3) Partial braking
(3
When the brake valve is actuated, an amount of hydraulic pressure is output as a ratio of the foot
force applied.
The spring assembly (8) beneath pedal plate (16) is designed in such a way that the braking
pressure changes depending on the angle. In the lower braking pressure range, the machine can
be slowed sensitively.
When the braking process is commenced, the upper spool is mechanically actuated via spring
assembly (8), and the lower spool is actuated hydraulically by spool. As spools (3) move
downward, they will first close returns (T1, T2) via the control edges, thus establishing a
connection between accumulator ports (P1, P2) and ports (BR1, BR2) for the wheel brake
cylinders. The foot force applied now determines the output braking pressure. The control spools
(3) are held in the control position by the force applied (spring assembly above the spools and the
hydraulic pressure below the spool (balance of forces).
After output of the braking pressure, spools (3) are in a partial braking position, causing ports (P1,
P2) and ports (T1, T2) to close and holding the pressure in ports (BR1, BR2).
(4) Full braking position
(4
When pedal is fully actuated, end position of the brakes is reached and a connection established
between accumulator ports (P1, P2) and brake cylinder ports (BR1, BR2). Returns (T1, T2) are
closed at this point.
When the braking process is ended, a connection is once again established between brake
cylinder ports (BR1, BR2) and return ports (T1, T2), closing accumulator ports (P1, P2).
The arrangement of spools in the valve ensures that even if one braking circuit fails the other
remains fully operational. This is achieved by means of the mechanical actuation of both spools
and requires slightly more pedal travel.
(5) Limiting the braking pressure
Pedal restriction bolt (23) on pedal plate (16) is used to limit the braking pressure.
(6) Failure of a circuit
In the event of the lower circuit failing, the upper circuit will remain operational. Spring assembly
(8) will mechanically actuate spool. In the event of the upper circuit failing, the lower circuit will
remain operational since the lower spool (3) is mechanically actuated by spring assembly (8) and
spool (3).
(7) Installation requirements
Return lines (T1, T2) must be connected directly to the tank.
The connecting lines must be installed is such a way as to permit proper bleeding.

4-14
(8) Maintenance of the brake valve
No special maintenance beyond the legal requirements is necessary.
When using high-pressure cleaners on the machine, please make sure that the water jet is not
aimed directly at the brake valve (to prevent damaging the bellows).
For safety reasons the whole of the brake valve must be replaced if parts other than those
listed above are damaged.
(9) Repair work
(9
When working on the braking system, always make sure that there is absolutely no pressure
in the system. Even when the engine is switched off there will be some residual pressure in
the system.
※ When doing repair work, make sure your environment is very clean.
Immediately close all open ports on the components and on pipes using plugs.
(10) Replacing the complete actuating mechanism
Carefully clamp the unit vertically in a fixture. The actuating mechanism can be removed by taking
out the three bolts. Make sure that spring assembly (8) does not fall out. When installing the new
actuating mechanism, make sure that spring assembly (8) is fitted in the right order. Tighten the
four bolts (25).
(11) Replacing the pedal cover
Pedal cover (18) is simply pulled of by hand. The new pedal cover is pushed over pedal (17) and
tightened manually. Fasten the bellows with the strap retainers.
(12) Replacing the bellows
To change bellows (19) it is advisable to remove pedal (17). For this purpose, loosen snap ring
(22) and knock out pin (20) using a mandrill. When knocking out the bolt, make sure that the
mandrill is applied to the side of the bolt without a knurl. Remove pedal (17) and bellows (19).
Now fit the new bellows and proceed in reverse order as described above. The upper portion of
bellows is fastened to piston, its lower portion to pedal plate (16) secure the bellows using clamps.

4-15
 5. CUT-OFF VALVE
1) STRUCTURE

3
4 C B
2
D D
5
P1

T
T1
PS

P PS1 A A
C B

SECTION A - A SECTION B - B
1 2

A1 A2

1 PS

P1

A3
A3 T1
A1

PS1
A2
B
P T

SECTION C - C SECTION D - D HYDRAULIC CIRCUIT

7407ABS11

1 Cut-off valve 4 Coil

2 Relief valve 5 Solenoid valve
3 Check valve

2) OPERATION
When the pump works, the oil under the pressure flows into P port.
The oil in P port is stored in the accumulator on A1 or A2 port.
As the pressure on P line rises to 150bar, the cut off valve (1) starts cut-offing and the oil in the P
port is unloaded. The pressure on P line goes down 120 bar by the minute leakage from valve and
other factors.
At this pressure, the cut-off valve starts cut-ining.
This process is repeated in the regular period of 30~40 seconds.

4-16
6. BRAKE ACCUMULATOR
1) STRUCTURE
81L1-0004 31EC-02190
Item
(item17) (item16)
Diameter 121 mm 136 mm
Mounting height 146 mm 160 mm
Norminal volume 0.75ℓ 1.0ℓ
Priming pressure 50 kgf/cm2 50 kgf/cm2

B Operating medium Oil Oil

Operating pressure Max 210 kgf/cm2 Max 200 kgf/cm2

A Thread M18×1.5 M18×1.5

Priming gas Nitrogen Nitrogen
C
A Fluid portion C Diaphragm
B Gas portion D Valve disk
D

75794BS09

2) OPERATION
(1) Purpose
Fluids are practically incompressible and are thus incapable of accumulating pressure energy. In
hydropneumatic accumulators, the compressibility of a gas is utilized to accumulate fluid. The
compressible medium used in the accumulators is nitrogen.
In braking systems, the purpose of the accumulators is to store the energy supplied by the
hydraulic pump. They are also used as an energy reserve when the pump is not working, as a
compensator for any losses through leakage, and as oscillation dampers.
(2) Operation
(2
The accumulator consists of a fluid portion (A) and a gas portion (B) with a diaphragm (C) as a
gas-tight dividing element. The fluid portion (A) is connected to the hydraulic circuit, causing the
diaphragm accumulator to be filled and the gas volume to be compressed as the pressure rises.
When the pressure falls, the compressed gas volume will expand, thus displacing the
accumulated pressure fluid into the circuit.
The diaphragm bottom contains a valve disk (D) which, if the diaphragm accumulator is
completely empty, closes the hydraulic outlet, thus preventing damage to the diaphragm.
3) Installation requirements
(3)
The accumulators can be fitted in the hydraulic circuit, directly on a component or in blocks on
suitable consoles.
They should be fitted in as cool a location as possible.
Installation can be in any position.

4-17
(4) Maintenance of the accumulator
No special maintenance beyond the legal requirements is necessary.
The accumulator should be checked annually. It should be replaced if the initial gas pressure has
fallen by more than 30% (please refer to Performance testing and checking of the accumulator).
(5) Disposal of the accumulator
Before the accumulator is scrapped, its gas filling pressure must be reduced. For this purpose,
drill a hole through gas chamber (B) using a drill approx. 3mm in diameter. The gas chamber is
located on the side opposite the threaded port above the welding seam around the center of the
accumulator.
※ Wear safety goggles when doing this job.
(6) Performance testing and checking of the accumulator
The accumulator is gradually pressurized via the test pump; until the initial gas pressure is
reached, the hydraulic pressure in the accumulator will rise abruptly. This is apparent from gauge
M. If the initial gas pressure is more than 30% below the prescribed value, the accumulator needs
to be replaced. If the measuring process needs to be repeated, wait for intervals of 3 minutes
between the individual tests. Any accumulator whose initial gas pressure is insufficient must be
scrapped following the instructions under Disposal of the accumulator
accumulator.
The amount of initial gas pressure can also be checked from the vehicle. Start the vehicle's
engine. The pump will now supply oil to the accumulators. Until the initial gas pressure is
reached, the hydraulic pressure in the accumulator will rise abruptly. This is apparent from the
gauge in the cab. If the initial gas pressure is more than 30% below the prescribed value, that
initial pressure lies outside the permissible range for at least one of the accumulators fitted in the
vehicle. This accumulator can be traced only by using the method described above, i.e. all
accumulators have to be individually tested. The accumulator whose initial gas pressure is
insufficient must be replaced and scrapped following the instruction under Disposal of the
accumulator.
accumulator

Accumulator
Pressure gauge(M)

Ball valve for

shutting off pump flow
Safety valve

Ball valve for

reducing pressure
75794BS10

(7) Repair work

When working on the braking system, always make sure that there is absolutely no
pressure in the system. Even when the engine in switched off there will be some residual
pressure in the system.
※ When doing repair work, make sure your environment is very clean.
Immediately close all open ports on the components and on pipes using plugs.
For safety reasons the accumulators need to be replaced as a whole if damaged.

4-18
7. PRESSURE SENSORS
1) STRUCTURE

Connector
Connector

H1
H1

H2 H2
G G
PARKING, CHARGING BRAKE STOP & CLUTCH CUT OFF
7579S4BS15

2) TECHNICAL DATA
H1 H2 Adjusting range Actuating pressure Voltage
Item Medium G
mm mm kgf/cm2 kgf/cm2 V
Parking pressure
Oil PF 1/4" 46.5 11 0 ~ 200 100 ± 5 Max 30
sensor
Charging pressure
Oil PF 1/4" 46.5 11 0 ~ 200 100 ± 5 Max 30
sensor
Brake stop & clutch cut
Oil PF 1/4" 46.5 11 1 ~ 100 5±1 Max 30
off pressure sensor

4-19
2) OPERATION
(1) Purpose
The pressure switches are used to visually or audibly warn the driver of the pressure within the
system.
(2) Make contact / circuit closer
The pressure switch can be fitted in the braking system or directly on one of its components.
The system pressure acts on an absorption area within the switch, making an electrical contact
as the pressure on that area is increased. The resulting current is used to activate a warning
facility, for instance.
(3) Break contact / circuit breaker
The pressure switch can be fitted in the braking system or directly on one of its components.
The system pressure acts on a absorption area within the switch, breaking an electrical contact
as the pressure on that area is increased. The current is now broken, e.g. to deactivate a warning
facility.
(4) Installation requirements
No special measures need to be taken.
(5) Maintenance of the pressure switch
No special maintenance beyond the legal requirements is necessary.
When using high-pressure cleaners on the vehicle, please make sure that the water jet is not
directed at the pressure switch (corrosion of contacts).
(6) Repair work
When working on the braking system, always make sure that there is absolutely no
pressure in the system. Even when the engine is switched off there will be some residual
pressure in the system.
※ When doing repair work, make sure your environment is very clean.
Immediately close all open ports on the components and on pipes using plugs.
※ For safety reasons the pressure switch needs to be replaced as a whole if damaged.

4-20
GROUP 2 OPERATIONAL CHECKS AND TROUBLESHOOTING

1. OPERATIONAL CHECKS
This procedure is designed so the mechanic can make a quick check of the system using a minimum
amount of diagnostic equipment. If you need additional information, read structure and function
function,
Group 1.
A location will be required which is level and has adequate space to complete the checks.
The engine and all other major components must be at operating temperature for some checks.
Locate system check in the left column and read completely, following the sequence from left to right.
Read each check completely before performing.
At the end of each check, if no problem is found (OK), that check is complete or an additional check is
needed. If problem is indicated (NOT OK), you will be given repair required and group location.
If verification is needed, you will be given next best source of information:

Chapter 2 : Troubleshooting
Group 3 : Tests and adjustments

4-21
※Hydraulic oil must be at operating temperature for these checks (refer to page 6-49).

Item Description Service action

Parking brake capacity Start engine. OK
check Check completed.
Fasten seat belt.
Seat belt must be worn
NOT OK
while doing this check to Release parking brake and put
Inspect parking brake. Go
prevent possible injury transmission in 2nd gear forward.
to group 3.
when machine stops
Drive machine at 8 km/hr and
suddenly.
switch parking brake ON.
ON LOOK/FEEL : Machine must
Release
come to a stop within 2 meters (6
feet) when parking brake is
P

engaged at 8 km/hr.
Transmission must shift to neutral.
Parking brake Turn parking brake to ON. OK
transmission lockout Check completed.
Place transmission in 1st forward.
check
P

NOT OK
Engine running. Slowly increase engine speed to
Go to transmission control
high idle.
circuit in section 3.
LOOK : Machine must not move.

4-22
 Item Description Service action
Service brake pump flow Stop engine. OK
check Check completed.
Operate brake pedal approximately
※ Hydraulic oil must be at
20 times. NOT OK
operating temperature
Start engine and run at low idle. Check for brake circuit
for the check.
leakage.
Engine OFF. Record number of seconds
required for low brake pressure Go to next page.
indicator lamp to go out.
IF OK
LOOK : Indicator lamp must go out I n s t a l l a c a p o n l i n e
in less than 4 seconds from time connected to inlet of brake
engine starts. valve and repeat pump
flow check.
NOTE : Indicator will not come on
approximately 1 second after If time does not decrease,
starting engine. check for wor n brake
pump.
Service brake capacity Turn clutch cut-off mode switch OK
check OFF. Check completed.
OFF

Engine running.
Apply service brakes, release park NOT OK
L

M H
brake and put transmission in 2nd Check brake pressure.
forward.
IF OK
Increase engine speed to high idle. Inspect brake disk.
LOOK : Machine may not move or
P

move at a very slow speed.

Repeat check three times to ensure
accurate results.

4-23
 Item Description Service action
Brake accumulator S t a r t a n d r u n e n g i n e fo r 3 0 OK
precharge check seconds. Check completed.
※The axles and hydraulic
Stop engine and turn start switch to NOT OK
oil must be at operating
ON and wait 5 seconds. Make sure brake pedal is
temperature for this
not binding and keeping
check. NOTE : Engine oil pressure lamp
brakes partially engaged.
will be on due to no engine oil
pressure. Bleed brakes in group 3.
Count the number of times the C h e c k b r a k e s y s t e m
brake pedal can be fully depressed pressure.
before the low brake pressure
NOT OK
warning lamp comes ON.
If light comes ON with
LOOK : Warning lamp must come e n g i n e r u n n i n g ,
ON in 1~5 applications. accumulator has lost it's
charge. Inspect and
Start engine and operate at low
recharge accumulator.
idle.
Observe cluster while applying
brake pedal with maximum force.
LOOK/LISTEN : Brake pressure
indicator must not come ON.
Brake system leakage Start engine and wait 30 seconds. OK
check Check completed.
Stop engine.
NOT OK
Wait 2 minutes.
If brake leakage is
Turn start switch to ON and wait 5 indicated with brakes
seconds. released, check leakage at
accumulator inlet check
LOOK : Brake oil pressure warning
valve and brake valve. If
lamp must not come ON within 2
brake leakage is indicated
minutes after stopping engine.
with brakes applied, check
for leakage at brake valve
and brake pistons.
Check individual
component leakage.

4-24
 Item Description Service action
S e r v i c e b ra ke p e d a l Slowly depress brake pedal. OK
check Check completed.
Listen for a hissing noise that
indicates oil is flowing to brake NOT OK
pistons. Inspect for debris under
brake pedal.
LISTEN/FEEL : A hissing noise
must be heard when pedal is
depressed.
Service and parking Position machine on gradual slope. OK
brake system drag Check completed.
Lower bucket approximately 50 mm
checks
(2 in) from ground.
Engine running NOT OK
Release parking and ser vice Adjust park brake.
brakes.
NOT OK
LOOK : Machine must move or
Check floor mat interfer-
coast.
P

ence to pedal or debris

NOTE : If machine does not move, build-up.
check brake pedals to be sure they
fully release when feet are removed IF OK
from pedals. Check for brake pressure
when brake is released.
Drive machine at high speed for
about 5 minutes.
Go to brake pressure test.
Brake drag is indicated if brake
areas in differential case are hot.
NOTE : Observe parking brake.
If disk is hot, parking brake drag is
indicated.
Clutch cut-off check Place clutch cut-off mode dial OK
switch in L position. Check completed.
Release parking brake. NOT OK
Adjust clutch cut-off switch.
Run engine at half speed in 1st
forward.
Firmly depress brake pedal.
F E E L : Tr a n s m i s s i o n m u s t
disengage when brake pedal is
depressed at 30% of pedal stroke.
OFF

NOTE : Clutch cut-off mode switch

L

M H
can be selected to operator
preference to match your loading
needs.

4-25
2. TROUBLESHOOTING
1) SERVICE BRAKE
Diagnose malfunction charts are arranged from most probable and simplest to verify, to least likely,
more difficult to verify. Remember the following steps when troubleshooting a problem :
Step 1. Operational check out procedure (see section 1)
Step 2. Operational checks (in this group)
Step 3. Troubleshooting
Step 4. Tests and adjustments (see group 3)

Problem Cause Remedy

Poor or no brakes Brake accumulator charge low. Do brake accumulator check.
Brake pump standby pressure Do brake pump standby pressure test.
low.
Brake pressure low. Do brake valve pressure test.
Air in system. Bleed brakes.
Worn brake surface material. Inspect brake surface material.
Leakage in brake valve. Do brake valve leakage test.
Leakage in brake piston seal. Check for an over filled differential.
Apply brakes and check for leakage from check
plug.
※It is normal for the oil level to be slightly
above the check plug.
Aggressive brakes Internal restriction in circuit. Remove lines and components.
Brake valve malfunction. Disassemble and inspect.
Low oil level. Check oil level.
Brakes drag Brake pedal not retur ning Inspect floor mat and pedal.
properly.
Debris holding valve partially Do brake valve pressure test.
open in brake valve.
Warped brake disk. Inspect brake disk.
Stuck brake piston. Repair.
Brakes lock up Brake valve malfunction. Clean or replace brake valve.

4-26
 Problem Cause Remedy
Brakes chatter Air in brake system. Do brake bleed procedure.
Worn brake surface material. Inspect brake surface material.
Wrong oil in differential. Drain.Refill.
H i s s i n g n o i s e w h e n Leakage in brake valve, or brake Do brake system leakage test.
brake pedal is held with piston.
engine stopped
Brake pressure warning M a l f u n c t i o n i n b r a k e l o w Replace switch.
light will not go out or pressure warning switch.
stays on excessively long
Brake accumulator pressure too Recharge accumulator.
after start-up
low.
L ow b r a ke p u m p s t a n d by Do brake pump standby pressure test.
pressure setting.
Leakage in pressure reducing Do pressure reducing valve manifold leakage
manifold block. test.
Leakage in brake system. Do brake system components leakage tests.
Worn brake pump. Do brake pump flow test.
Leakage in par king brake Do parking brake pressure test.
solenoid.

2) PARKING BRAKE MALFUNCTIONS

Problem Cause Remedy

Brake will not hold Pads not adjusted correctly. Adjust parking brake.
Malfunctioning parking brake Inspect and replace.
solenoid.
Worn brake disk and / or brake Disassemble, inspect, repair.
pads.
Brake piston hangs up in bore. Remove and inspect. Repair.
Brake disk overheats Pads out of adjustment. Adjust parking brake.
Brake not released. Release parking brake.
Disassemble, inspect brake.
Repair if necessary.
Inspect for loosen or broken lines between brake
pressure switch and indicator on dash.
Parking brake indicator in Faulty wiring or switch. Inspect for loose or broken lines between brake
monitor does not come pressure switch and indicator on dash.
on when brake applied Inspect for a faulty indicator on dash. Replace if
necessary.
Brake will not apply Pads out of adjustment. Adjust parking brake.
Malfunctioning wiring, switch, or Check electric circuit.
solenoid.
Restriction between brake valve Remove hose and inspect. Replace.
and brake.

4-27
GROUP 3 TESTS AND ADJUSTMENTS

1. PARKING BRAKE PERFORMANCE

1) MEASUREMENT
EASUREMENT CONDITION
(1) Tire inflation pressure : Specified pressure
(2) Road surface : Flat, dry, paved surface
with 1/5 (11˚20') gradient.
(3) Machine : In operating condition 20%
gradient 11 20'
Item Standard valve
Parking brake Keep machine on 20%
performance (11˚20') gradient 73094BS17

2) MEASURING PROCEDURE
(1) Start the engine and drive the machine
straight up a 1/5 gradient with the bucket
unloaded.
(2) Depress the service brake, place the gear
selector lever in neutral, then stop the
engine.
(3) Turn the parking brake switch ON, then 20%
11 20' gradient
slowly release the service brake pedal
and the machine must be kept stopped.
※ The measurement must be made with
the machine facing either up or down
73094BS18
the slope.

4-28
2. ADJUSTMENT OF PARKING BRAKE
1) Remove screws complete with nuts and
seals. Replace seals, apply grease to the
screws and install all parts into the arm.

7409RAX190

2) Adjust screws (31) to obtain a jut of

30±0.5 mm in relation to the arm.

74095TA19

3) Lock into position with nuts (30).

※ Hold screws (31) into position while locking
the nuts (30) ; after locking, check the jut of
screws (31) once more.

74095TA20

4-29
3. HYDRAULIC BRAKE BLEEDING PROCEDURE
Escaping fluid under pressure can B
penetrate the skin causing serious injury.
Avoid the hazard by relieving pressure B
before disconnecting hydraulic or other
lines. Tighten all connections before
applying pressure. B
Search for leaks with a piece of cardboard.
Protect hands and body from high B
pressure fluids.
※ If an accident occurs, see a doctor
immediately. Any fluid injected into the skin
must be surgically removed within a few
hours or gangrene may result.
Doctors unfamiliar with this type of injury A
should reference a knowledgeable medical
source.
Two people are required to bleed brake
system oil, one to operate brake valve and
other to open and close bleed screws. A
1) Install frame locking bar. Engage parking
brake.
2) Put a clear plastic tube on bleed screw (B)
to route low to hydraulic oil tank filler tube
or container (A).
3) Start engine and run at low idle.
4) Push and hold brake pedal down until
Safety lock bar
brake bleeding procedure is complete.
※ If bubbles continue for more than 2
minutes, stop bleeding procedure.
Check for and correct problem, then
continue.
5) Open on bleed screw on differential and
axle assembly until hydraulic oil starts to
flow. Close bleed screw when oil is free of
air. Release brake pedal.
6) Repeat steps 1)~5) for each bleed screw.
7) Push either brake pedal and hold down.
73094BS19
8) Check hydraulic oil level.

4-30
GROUP 4 DISASSEMBLY AND ASSEMBLY

1. BRAKE PUMP
1) MAIN
AIN ASSEMBLY

Outlet

2
Brake pump

6
3
Inlet A
B
2
C
1
5
D

Outlet
13
12
A
7

8 11
Inlet

7
10
Fan pump
14

Assembly direction of bushing block

7309S4BS07

1 Housing sub assy 6 Multi spacer 11 Rear cover

2 Bushing block sub assy 7 Bush block sub assy 12 Washer
3 Shaft gear 8 Joint drive gear 13 Bolt
4 Driven gear 9 Driven gear 14 Connector
5 Front cover sub assy 10 Housing sub assy

4-31
(1) Prepare all parts and clean it.
(2) Prepare M10 torque wrench, oil pump and 1, 2, 5, 7, 10 sub assembly status.
(3) When you assemble, front cover sub assy (5) is based on a front view.
(4) Main assembly order
① Front cover sub assy (5) is based on a front view in drawing, check sense of rotation (CW) and
assembling shaft gear's upper direction.
② At first, one of bushing block sub assy (2) point to same position of figure. After you assemble
drive gear (3) and driven gear (4), you assemble bushing block sub assy (2).
③ Put oil on the assembled parts (2, 3, 4), lubrication for the gear to rotate and assemble front
cover sub assy (5) to A direction.
④ Check the outlet port based on housing sub assy (1) drawing and contamination of part's inside.
Coated oil parts are assembled in the direction vertical and horizontal.
⑤ Assemble multi spacer(6) as shown in the figure and connector (14) put in joint drive gear's(8)
hole.
⑥ One of bush block sub assy(7) point to same position of figure.
After you assemble joint drive gear(8) and driven gear(9), you assemble bush block sub assy.
⑦ Put oil on the assembled parts (7,8,9), lubrication for the gear to rotate assemble multi
spacer(6) to A axis direction.
⑧ Check the outlet port based on housing sub assy(10) drawing and contamination of part's inside.
Coated oil parts are assembled in the direction verticcal and horizontal.
⑨ Assemble rear cover(11) as shown in the figure.
⑩ Washer(12) put in bolt(13), assemble in order of A-D-B-C and tighten bolts same order using
toque wrench
·Tightening torque : 4.6±0.5 kgf·m (33.3±3.7 lbf·ft)
(5) Complete assembly.
(6) Dissembly is assembly's order in reverse.
(7) You proceed running-in using performance test device.
(8) Install it, and use.

4-32
2) SUB ASSEMNLY
※ Beware of scratches, damages and foreign
materials.
※ Grease must have good lubricity and
viscosity.
※ You must prepare snap ring tool and
retainal seal special tool.
(1) Fron
Frontt cover assy
1
① After enough grease on the surface of Direction B
retainal seal (2). It is assembled front
cover (1) using retainal seal special tool. 2
3
※ Lip's direction toward A direction should
be assembled and because of the risk of
Direction A
damage should be used only special tool.
② After you put snap ring tool in 2 holes of Direction A Lip

snap ring (3), grasp it and snap ring (3) is

assembled front cover's (1) groove using
Direction B
snap ring tool. 7407B4BS20

(2) Housing assy

① After enough grease on the surface of 1
D-rings (2), those should be assembled
grooves of housing's (1) both sides 2

closely.
2
※ A side of D-ring (2) should be assembled
side of housing (1) closely.

Face A

7407B4BS21

(3) Bushing block assy

① After enough grease on the surface of
channel seal (2), it should be assembled 2
groove of bushing block (1). 3
※ A side of channel seal(2) should be
assembled side of bushing block (1)
1
closely.
② After enough grease on the surface of
back-up seal (3), it should be assembled
groove of channel seal (2).
Face B Face A
※ A side of back-up seal (3) should be
assembled inside of channel seal (2)
closely. 7407B4BS22

4-33
3) RUNNING-IN

Pressure gauge

Test unit Variable

restrictor
Microbic filter

Flow
meter
Relief valve

Strainer

Tank
(730TM-3C)4-48

(1) A unit which has been re-assembled with either new gears, bushes or body, must be carefully
run-in before it is subjected to full working conditions.
(2) Ideally this should be done on a test rig (see figure) where pressure can be gradually applied and
any wipings from the body cut-in arrested by filters.
(3) It is recommended that the unit is run-in at 1500 rpm, initially, at zero pressure for one minute then
in stages with the pressure increased by 500 psi every minute, until maximum rated pressure has
been attained. Frequently check the system temperature, ensuring that it does not exceed the
maximum permissible figure of 80˚C. If the temperature exceeds the system or unit specification
the test must be delayed and operated off-load until acceptable temperatures are obtained.

4-34
 SECTION 5 STEERING SYSTEM

Group 1 Structure and Function ---------------------------------------------------------------------------------- 5-1

Group 2 Operational Checks and Troubleshooting ---------------------------------------------------- 5-15
Group 3 Tests and Adjustments ----------------------------------------------------------------------------------- 5-21
Group 4 Disassembly and Assembly -------------------------------------------------------------------------- 5-27
 SECTION 5 STEERING SYSTEM
GROUP 1 STRUCTURE AND FUNCTION

1. OUTLINE
The steering system of this machine consists of a fixed-displacement pump supplying a load sensing
steering system and an open center loader system.
The components of the steering system are :
·Steering pump (1st pump)
·Steering unit
·Overload valve block
·Priority valve
·Steering cylinders
The steering pump, the first pump of main pump, draws hydraulic oil from the hydraulic tank.
Outlet flow from the pump flows to the priority valve. The priority valve preferentially supplies flow, on
demand, to the steering unit. When the machine is steered, the steering unit routes flow to the
steering cylinders to articulate the machine.
When the machine is not being steered, or if pump flow is greater than steering flow, the priority valve
supplies flow to the loader system.
That is, output flow from the steering pump enters into the first pump of main pump for the operation
of the attachment.

5-1
2. HYDRAULIC CIRCUIT

10

LH RH

34

5
L

LS

Priority valve spool CF EF

6
Brake system MCV
LS

RCV lever
Fan drive moter
Return line 1

30
PS

23
M1
Return line
A P1

30 24 Return line
M2
PS

29 21
P2
25 26
28
M

7409S5SE01

1 Main pump 23 Air breather 29 Check block (option)

5 Steering unit 24 Hydraulic tank 30 Pressure sensor (option)
6 Priority valve 25 Return filter 34 Cushion valve
10 Steering cylinder 26 Bypass valve
21 Oil cooler 28 Motor pump (option)

5-2
1) NEUTRAL

10

LH RH

34

5
L

LS

CF EF

6 MCV
LS
D
P

RCV lever
Brake system Fan drive moter
1
Return line

23
Return line

24 Return line
26 21
25

7409S5SE02

The steering wheel is not being operated so control spool (G) does not move.
The oil from the steering pump enters port P of the priority valve and the inlet pressure oil moves the
spool (D) to the right.
Oil flow into LS port to the hydraulic tank (24) through orifice and return filter.
So, the pump flow is routed to the loader system (Main control valve) through the EF port.

5-3
2) LEFT TURN

10

LH RH

34

5
L

G
E
R

LS

CF EF

6 MCV
LS
D
P

RCV lever
Brake system Fan drive moter
1
Return line

23
Return line

24 Return line
26 21
25

7409S5SE03

When the steering wheel (E) is turned to the left, the spool (G) within the steering unit (5) connected
with steering column turns in left hand direction.
At this time, the oil discharged from the steering pump flows into the spool (G) of the steering unit (5)
through the spool (D) of priority valve (6) and flows into the gerotor(H).
Oil flow from the gerotor flows back into the spool (G) where it is directed out the left work port (L) to
the respective chamber of the steering cylinders (10).
Oil returned from left and right cylinder returns to hydraulic tank through the spool of the steering unit.
When the above operation is completed, the machine turns to the left.

5-4
3) RIGHT TURN

10

L.H R.H

34

5
L

E
R

LS

CF EF
6
MCV
LS
D
P

RCV lever
Brake system Fan drive moter
2 1
Return line

23
Return line

24 Return line
26 21
25

7409S5SE04

When the steering wheel (E) is turned to the right, the spool (G) within the steering unit (5)
connected with steering column turns in right hand direction.
At this time, the oil discharged from the steering pump flows into the spool (G) of the steering unit (5)
through the spool (D) of priority valve (6) and flows into the gerotor (H).
Oil flow from the gerotor flows back into the spool (G) where it is directed out the right workport to the
respective chamber of the steering cylinders (10).
Oil returned from left and right cylinder returns to hydraulic tank through the spool of the steering unit.
When the above operation is completed, the machine turns to the right.

5-5
3. STEERING UNIT
1) STRUCTURE

21 2 5
38 31
37 6
36
35 33
34 7

8
39 2
34
35 10
39 36
38 9
37 11
12
13
14

13
15
19
13
16
17

18

7407SE05

1 Dust seal ring 11 O-ring 21 Complete relief valve without seat

2 Housing, spool, sleeve 12 Intermediate plate 31 Set of o-rings
3 Ball 13 O-ring 33 Rolled pin
4 Thread bushing 14 Distributor plate 34 Screw
5 Roto glyd ring 15 Gearwheel set 35 Shock valve
6 Bearing assembly 16 End cover 36 Spring
7 Ring 17 Washer 37 O-ring
8 Cross pin 18 Screw with pin 38 Plug
9 Set of spring 19 Screw 39 Housing, check valve
10 Cardan shaft

5-6
2) OPERATION

9 10

2 39
A A

14
15
16

SECTION A - A

7407SE06

The steering unit consists of a rotary valve and a rotary meter.

Via a steering column the steering unit is connected to the steering wheel of the machine.
When the steering wheel is turned, oil is directed from the steering system pump via the rotary
valve (spool and sleeve) and rotary meter (gear wheel set) to the cylinder ports L or R, depending
on the direction of turn. The rotary meter meters the oil flow to the steering cylinder in proportion to
the angular rotation of the steering wheel.
Spool is connected directly to the drive shaft (10) of steering wheel. It is connected to sleeve by
cross pin (8) (not in contact with the spool when the steering wheel is at neutral) and neutral
position spring (9).
Cardan shaft (10) is meshed at the top with cross pin (8) and forms one unit with sleeve.
At the same time, it is meshed with gear rim of the gerotor set by spline.
There are four ports in valve body. They are connected to the pump circuit, tank circuit, and the
head, and left and right steering cylinder. In addition, the pump port and tank port are connected
inside the body by the check valve. Therefore, if there is any failure in the pump of engine, oil can
be sucked in directly from the tank through the check valve.

5-7
4. PRIORITY VALVE
1) STRUCTURE

5 6 8 2 1 7 4 3

LS

EF CF

7309S5SE30

CF EF
Port Port name Port size
P From main pump 7/8 - 14 UNF
CF To steering unit P port 3/4 - 16 UNF
LS
EF To MCV 7/8 - 14 UNF
LS To steering unit LS port 7/16 - 20 UNF P
HYDRAULIC CIRCUIT

1 Body 4 Spring 7 Orifice

2 Spool 5 Plug 8 Orifice
3 Nipple 6 O-ring

5-8
 2) OPERATION
(1) Neutral

A
4 A 5
CF EF
P

LS

LS

EF CF
LOADER ACTUATED(D)

7309S5PR07

The priority valve is a pressure control valve that maintains priority pressure to the closed center
steering unit. With the steering unit in neutral, flow through is blocked and all flow through the priority
valve is directed out the EF port to the main control valve.
With the engine off, the spool (4) is pushed to the left (Viewed from sectional drawing at previous page)
by the spring (5). The passage to the EF port is blocked while the passage to the CF port is open.
When the machine is first started, all pump flow is routed to the steering unit which blocks the flow.
With the flow blocked, the pressure increases.
Steering inlet pressure is supplied through the pilot orifice to the left end of the spool. This causes the
priority valve spool(4) to shift to the right against the spring and open the EF port.
As long as the steering unit is in neutral, just enough pressure is maintained at the steering unit to keep
the priority valve spool shifted to the right.
The operating pressure in the loader system has no effect on the operation of the priority valve. With
the loader actuated in relief (D), the priority valve will not shift until the machine is steered.
Flow through the priority valve spool passes from the CF port through the orifice (A) and into the LS
port. It flows through the steering unit LS passage which is routed to return when the steering unit is in
neutral. This provides a warm-up circuit for the steering unit to prevent binding of the steering unit due
to oil temperature extremes.

5-9
 (2) Midturn

A
4 A 5
CF EF
P

LS

LS

EF CF
FULL STEER RATE(D)

7309S5PR09

When the machine is steered, load sensing pressure from the steering unit flows through the orifices
LS port in the priority valve. Load sensing pressure plus spring (5) force move the spool (4) to the
against the pilot pressure on the left end of the spool. This restricts flow to the loader through the EF
port while the CF port is opened to the steering unit.
The load sensing circuit is control circuit that routes steering workport pressure to the spring side of the
priority valve spool. It allows the priority valve spool to sense the pressure that is required to steer the
unit under varying conditions.
During normal steering conditions, oil is entered into the load sensing circuit through an orifice in the
steering unit. When steering at the full steer rate (D), the orifice opens to an unrestricted passage. At
low engine speed, the spool will shift to the full left position, directing all flow to the steering unit. At
high idle, the steering system can use about one-half of the pump flow. Therefore, the excess oil flows
to the main control valve.
The load-sensing circuit receives the majority of its flow from the load sensing orifice in the steering unit.
Some flow is also supplied from the CF port through orifice (A) in the priority valve spool.

5-10
 (3) Full turn

4 5

P
CF EF

LS

P
LS

EF CF

7309S5PR08

When the machine is steered to a full turn, the frames bottom against the steering stops.
Pressure to the steering unit (Pilot pressure), which is sensed at the left end of the priority valve spool
(4), continues to increase until it can move the spool to the right against the load sensing pressure plus
spring force. At this time, all oil flows out of the EF port to the main control valve.
If the loader attachment is being operated while steering, the loader function will slow until the machine
reaches the steering stops. At that time, the loader cycle speed will increase until the machine is
steered again.

5-11
5. CUSHION VALVE
1) STRUCTURE

B A

B A
13

16 15 5 14 8 1 2 3 6 7 5 4

17 13 12 11 10 9

SECTION B - B SECTION A - A
7607SE18

1 Housing 7 Back ring 13 Plug

2 Poppet 8 Orifice 14 Plug
3 Spring 9 Plug 15 Spring
4 Valve seat 10 O-ring 16 Poppet
5 O-ring 11 Spring 17 Plug
6 O-ring 12 Spool

5-12
 2) OPERATION

L R
B A

B A

16 8 2 3

Check valve Pilot valve

section section

Main valve
section

SECTION B - B SECTION A - A

12 11 9

7607SE19

The cushion valve is a valve that eliminates steering jerk motion. It makes a higher pressurized oil to
flow into another line in order to prevent the shock on steering system.
The pressure by rapid supplied pressurized oil from R port is higher than the spring (3) force, so it press
and open the poppet (2). Then the oil flows to the central groove of the spool (12), and flows to L port
through the poppet of the check valve (16) on L port side.
At this time, this pressurized oil flows to the pressure area of the plug (9) through the orifice (8), and this
force is higher than the spring (11) force plus the oil pressure on L port side, so the spool (12) is shifted
to the right. The flow of the supplied oil to L port side through the poppet (2) from R port side is trapped.
The flow of this instant oil makes the function of the cushion. After this operation, the normal steering
operation is not affected because this valve is not operated any longer.
Also, for the response of the pressure when the operation is slow as a cushion effect is not required, the
spool (12) is closed before the poppet (2) is opened, so this valve is not operated.

5-13
6. STEERING CYLINDER
1) STRUCTURE

3 5,4 12 7,6 8 11,10 9 2 1 13 16 14 15 17 25 24

22,23

19,20,21 18

73095SE07

1 Tube assy 10 O-ring 19 U-bolt

2 Rod assy 11 Back up ring 20 Hexagon nut
3 Gland 12 O-ring 21 Spring washer
4 Dust wiper 13 Piston 22 Bushing
5 Retaining ring 14 Piston seal 23 Dust seal
6 Rod seal 15 Wear ring 24 Spherical bearing
7 Back up ring 16 O-ring 25 Retaining ring
8 Step seal 17 Nylon nut
9 Du bushing 18 Pipe assy

2) OPERATION
This machine use to cross connected cylinder for steering operation.
The steering cylinder use a gland (3) to remove piston and sealed seals. Dust wiper (4) located on
the in side of the gland protects cylinder inner parts from dust. The piston (13) is fastened to the
rod (2) by a nut (17).
The piston uses a single wear ring (15) with a piston seal (14) to seal between the piston and tube.
The gland seals against the tube with two O-rings. The rod is sealed against the gland with a rod
seal (6).

5-14
GROUP 2 OPERATIONAL CHECKS AND TROUBLESHOOTING

1. OPERATIONAL CHECKS
This procedure is designed so the service man can make a quick check of the steering system using
a minimum amount of diagnostic equipment. If you need additional information, prefer to structure
and function in group 1.
A location will be required which is level and has adequate space to complete the checks.
The engine and all other major components must be at operating temperature for some checks.
Locate system check in the left column and read completely, following this sequence from left to right.
Read each check completely before performing.
At the end of each check, if no problem is found(OK), that check is complete or an additional check is
needed. If problem is indicated(NOT OK), you will be given repair required and group location.
If verification is needed, you will be given next best source of information :

·Chapter 2 : Troubleshooting
·Group 3 : Tests and adjustments

5-15
※Hydraulic oil must be at operating temperature for these checks (refer to page 6-49).
Item Description Service action
Steering unit check Run engine at low idle. OK
Check completed.

A
Turn steering wheel until frames are
at maximum right (A) and then left NOT OK

B
(B) positions. Go to next check.
L O O K : Fra m e s mu s t m ove
smoothly in both directions.
When steering wheel is stopped,
frames must stop.
FEEL : Excessive effort must not be
required to turn steering wheel.
NOTE : It is normal for steering to
drift from stops when steering
wheel is released.
Steering system leakage Turn steering wheel rapidly until OK
check frames are against stops. Check completed.
Heat hydraulic oil to Left Right
Hold approximately 2 kg on steer- NOT OK
operating temperature.
ing wheel. Do steering system leakage
Run engine at high idle.
test in group 3 to isolate the
Count steering wheel revolutions
leakage.
for 1 minute.
Repeat test in opposite direction.
LOOK : Steering wheel should
rotate less than 5 rpm.
NOTE : Use good judgment;
Excessive steering wheel rpm does
not mean steering will be affected.
Priority valve low press- Park machine on a hard surface. OK
ure check Check completed.
Hold brake pedal down.
NOT OK
Run engine at high idle.
Do priority valve pressure
Steer machine to the right and left test.
as far as possible.
LOOK : Machine must turn at least
half way to the right and left stops.
Priority valve high Steer to steering stop and release OK
pressure check wheel. Check completed.
Roll bucket back and hold over NOT OK
Run engine at high idle.
relief and observe engine rpm. Priority pressure is set too
high. Do priority valve
Turn wheel to steering stop and
pressure test.
hold, observe engine rpm.
LOOK : Steering stall engine rpm
must be higher than hydraulic stall
rpm.

5-16
2. TROUBLESHOOTING
※ Diagnose malfunction charts are arranged from most probable and simplest to verify, to least
likely, more difficult to verify. Remember the following steps when troubleshooting a problem :
Step 1. Operational check out procedure (See group 3 in section 1)
Step 2. Operational checks (In this group)
Step 3. Troubleshooting
Step 4. Tests and adjustments (See group 3)

Problem Cause Remedy

No steering Low oil level. Add recommended oil.
Restricted suction line. Check.
Failed hydraulic pump. Remove and inspect return filter for metal
pump particles.
Failed main hydraulic pump drive. Remove main hydraulic pump and
inspect drive gear.
Stuck priority valve spool. Remove and inspect priority valve spool.
Broken priority valve spring. Remove and inspect spring.
Relief valve in steering unit stuck open. Do relief cartridge leakage test in group 3.
Failed hydraulic lines. Check.
Slow or hard steering Too much friction in the mechanical parts of Lubricate bearings and joints of frame or
the machine. cylinders or repair if necessary.
Check steering column installation.
Cold oil. Warm the hydraulic oil.
Low priority valve pressure setting. Do priority valve pressure test.
Worn hydraulic pump. Do hydraulic pump performance check.
Sticking priority valve spool. Remove and inspect.
Broken priority valve spring. Remove and inspect.
Pinched or restricted LS line. Inspect line. Do priority valve LS port
flow test in group 3.
Low system relief valve setting. Test and adjust if necessary.
Low overload relief valves setting. Test and adjust if necessary.

5-17
 Problem Cause Remedy
C o n s t a n t s t e e r i n g t o Air in system. Check for foamy oil.
maintain straight travel
Leakage in steering system. Do steering system leakage check.
Worn steering unit. Do steering unit neutral leakage test in
group 3.
Leaf spring without spring force or broken. Replace leaf springs.
Spring in overload relief valve broken. Replace overload relief valve.
Gear wheel set worn. Replace gear wheel set.
CCylinder seized or piston seals worn. Replace defects parts.
S l o w s t e e r i n g w h e e l Leakage in steering system. Do steering system leakage check.
movement will not cause
Worn steering unit gerotor. Do steering unit leakage check.
any frame movement
Steering wheel can be Leakage in steering system. Do steering system leakage check.
turned with frames
against steering stop
Steering wheel turns with Broken steering column or splined of Remove and inspect.
n o r e s i s t a n c e a n d steering unit.
Start engine and check steering opera-
causes no frame move-
Lack of oil in steering unit. tion.
ment
Leakage in steering system. Do steering system leakage test in group
3.
Erratic steering Air in oil. Check for foamy oil.
Low oil level. Add recommended oil.
Sticking priority valve spool. Remove and inspect spool.
Loose cylinder piston. Remove rod to inspect piston.
Damaged steering unit. Remove and inspect.
Spongy or soft steering Air in oil. Check for foamy oil.
Low oil level. Add recommended oil.
Free play at steering Loose steering wheel nut. Tighten.
wheel
Worn or damaged splines on steering Inspect.
column or valve.
Steering unit binding or Binding in steering column or misalignment Inspect.
steering wheel does not of column.
immediately retur n to
High return pressure. Check for a pinched or damaged return
neutral when released
line.
Contamination in steering unit. Inspect hydraulic filter for contamination.
Repair cause of contamination.
Flush hydraulic system.

5-18
 Problem Cause Remedy
Steering unit locks up Large particles of contamination in steer- Inspect hydraulic filter for contamination.
ing unit. Repair cause of contamination.
Flush hydraulic system.
★ Thermal shock Do priority valve LS port flow test in
group 5.
This oil flow provides a warm-up flow to
steering unit when not using the steering.
Worn or damaged steering unit. Repair or replace steering unit.
Abrupt steering wheel Improperly timed gerotor gear in steering Time gerotor gear.
oscillation unit.
Steering wheel turns by Lines connected to wrong port. Reconnect lines.
itself
Worn or damaged steering unit. Repair or replace steering unit.
Vibration in steering High priority valve setting. Do priority valve pressure test.
system or hoses jump
Neutral position of steer- Steering column and steering unit out of Align the steering column with steering
ing wheel cannot be line. unit.
obtained, i.e. there is a
Too little or no play between steering Adjust the play and, if necessary, shorten
tendency towards
column and steering unit input shaft. the splines journal.
"motoring"
Pinching between inner and outer spools. Contact the nearest service shop.
"Motoring" effect. Leaf springs are stuck or broken and Replace leaf springs.
The steering wheel can have therefore reduced spring force.
turn on its own
Inner and outer spools pinch, possibly Clean steering unit or contact the near-
due to dirt. est service shop.
Return pressure in connection with the Reduce return pressure.
reaction between differential cylinder and
steering unit too high.
Backlash Cardan shaft fork worn or broken. Replace cardan shaft.
Leaf springs without spring force or Replace leaf springs.
broken.
Worn splines on the steering column. Replace steering column.
Jerky steering LS port orifice missing. Inspect orifice.
Orifice in top end of priority valve spool Disassemble and inspect.
missing.
★ Thermal shock is caused by a large temperature differential (Approx 30°C, 50°F) between the
steering unit and hydraulic oil. If the steering is not operated for a long period of time and the
orifice in the bottom of the priority valve spool is plugged, the steering unit may bind up when
the steering is operated if the hydraulic oil is hot enough.

5-19
 Problem Cause Remedy
" S h i m my " e f fe c t T h e Air in the steering cylinder. Bleed cylinder.
steered wheels vibrate Find and remove the reason for air collec-
(Rough tread on tires tion.
gives vibrations)
Mechanical connections or wheel bearings Replace worn parts.
worn.
High priority valve setting pressure. Set pressure as regular value.
Steering wheel can be Oil is needed in the tank. Fill with clean oil and bleed the system.
turned the whole time
Steering cylinder worn. Replace or repair cylinder.
without the steered
wheels moving Gear wheel set worn. Replace gear wheel set.
Spacer across cardan shaft forgotten. Install spacer.
Steering wheel can be One or both anticavitation valves are Clean or replace defect or missing
turned slowly in one or leaky or are missing in overload relief valves.
both directions without valves.
the steered wheels
One or both overload relief valves are Clean or replace.
turning
leaky.
Steering is too slow and Insufficient oil supply to steering unit, Replace pump or increase number of rev-
heavy when tr ying to pump defective or number of revolutions olutions.
turn quickly too low.
Relief valve setting too low. Adjust valve to correct setting.
Relief valve sticking owing to dirt. Clean the valve.
Spool in priority valve sticking owing to Clean the valve, check that spool moves
dirt. easily without spring.
Too weak spring in priority valve. Replace spring by a stronger.
"Kick back" in steering Fault in the system. Contact authorized man or shop.
wheel from system.
Kicks from wheels.
H e a v y k i c k - b a c k i n Wrong setting of cardan shaft and gear- Correct setting as shown in group 4.
steering wheel in both wheel set.
directions
Tu r n i n g t h e s t e e r i n g Hydraulic hoses for the steering cylin- Connect lines to correct ports.
w h e e l a c t i v a t e s t h e ders have been switched around.
steered wheels opposite
Hard point when starting Spring force in priority valve too weak. Replace spring by a stronger.
to turn the steering
Air in LS and / or PP line. Bleed LS and PP line.
wheel
Clogged orifices in LS or PP side in Clean orifices in spool and in connecting
priority valve. plugs for LS and PP.
Oil is too thick(Cold). Let machine run until oil is warm.
Too little steering force Pump pressure too low. Correct pump pressure.

5-20
GROUP 3 TESTS AND ADJUSTMENTS

1. HYDRAULIC OIL CLEAN UP PROCEDURE USING PORTABLE FILTER CADDY

※ Service equipment and tool
·Portable filter caddy
·Two 4000 mm × 1" 100R1 Hoses
·Quick disconnect fittings
·Discharge wand
·Connectors
※ Steering system use oil from hydraulic oil
tank. Flush all lines in the steering system.
Disassemble and clean major compon-ents
for steering system.
Steering components may fail if steering
system is not cleaned after hydraulic oil
tank contamination.

1) If hydraulic system is contaminated due to

a major component failure, remove and dis-
assemble steering cylinders to clean debris
from cylinders.
2) Install a new return filter element. Inspect
filter before installing new element.
※ For a failure that creates a lot of debris,
remove access cover from hydraulic oil
tank. Drain and clean hydraulic oil tank of
fill the specified oil to hydraulic oil tank
through upper cover.
3) To minimize oil loss, pull a vacuum in
hydraulic oil tank using a vacuum pump.
Connect filter caddy suction line to drain
port at bottom of hydraulic oil tank using
connector. Check to be sure debris has not
closed drain port.
4) Put filter caddy discharge line into hydraulic
oil tank filler hole so end is as far away from
drain port as possible to obtain a thorough
cleaning of oil.

5-21
5) Start the filter caddy. Check to be sure oil is
flowing through the filters.
Operate filter caddy approximately 10 min-
utes so oil in hydraulic oil tank is circulated
through filter a minimum of four times.
※ Hydraulic tank capacity : 92ℓ(24.3 U.S. gal)
Leave filter caddy operating for the next
steps.
Start the engine and run it at high idle.
6) For the most effective results, cleaning pro-
※ cedure must start with the smallest capacity
circuit then proceed to the next largest
capacity circuit.
Operate all functions, one at a time, through
7) a complete cycle in the following order:
Clam, steering, bucket, and boom. Also
include all auxiliary hydraulic functions.
Repeat procedure until the total system
capacity has circulated through filter caddy
seven times, approximately 30 minutes.
Each function must go through a minimum
of three complete cycles for a through
cleaning for oil.
Filtering time for machines with auxiliary
※ hydraulic functions must be increased
because system capacity is larger.
Stop the engine. Remove the filter caddy.
8)
Install a new return filter element.
9)
Check oil level in hydraulic oil tank ; Add oil
10) if necessary.

5-22
2. TEST TOOLS
1) CLAMP-ON ELECTRONIC TACHOMET-
ER INSTALLATION
· Service equipment and tools
B
Tachometer
A : Clamp on tachometer.
Remove paint using emery cloth and
C
connect to a straight section of injec-
tion line within 100 mm (4in) of pump.
Finger tighten only-do not over tighten. D
B : Black clip (-). Connect to main
frame. A
C : Red clip (+). Connect to transducer.
D : Tachometer readout. Install cable. 75795SE32

2) DIGITAL THERMOMETER INSTALLATION

· Service equipment and tools
Digital thermometer
A : Temperature probe.
Fasten to a bare metal line using a A
C
tie band. Wrap with shop towel.
B
B : Cable.
C : Digital thermometer.

75795SE33

3) DISPLAY MONITOR TACHOMETER

The display monitor tachometer is accurate
enough for test work.

75795SE35

5-23
3. STEERING SYSTEM RESTRICTION TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed High idle
Maximum pressure 20 MPa (20 bar, 285 psi)
at steering unit
· GAUGE AND TOOL
Gauge 0~7 MPa (0~70 bar, 0~1000 psi) 2EA
· This test will check for restrictions in the
steering system which can cause overheat-
ing of hydraulic oil.
1) Install temperature reader.
(see temperature reader installation proce-
dure in this group). P

2) Heat hydraulic oil to specifications.

(see hydraulic oil warm up procedure at
A
page 6-49).
3) Connect fitting (A) and install gauge.
Do not operate steering or loader funct-
ions or test gauge may be damaged.
4) Run engine at specification and read pres-
sure gauges.
If pressure is more than specification at the
steering unit, inspect priority spool in MCV
for a stuck spool. Make sure orifice plugs
are installed in ends of priority spool. 74033ASE16

Check for plugged orifice in priority spool

SX port of MCV.

5-24
4. STEERING UNIT LEAKAGE TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed High idle
Maximum leakage 10ℓ/min
Cap fitting
· GAUGE AND TOOL
Temperature reader
Measuring container (approx 20ℓ)
Stop watch Steering unit

1) Install frame locking bar to prevent machine

from turning.
2) Install temperature reader.
(see temperature reader installation proce-
dure in this group).
3) Heat hydraulic oil to specifications.
(see hydraulic oil warm up procedure at
page 6-49).
4) Disconnect return hose from fitting.
Install cap fitting.
5) Run engine at specifications. Rotate
steering wheel against locking bar using
approximately 1.2 kgf·m of force.
Measure oil flow from return hose for 1
minute. Safety lock bar

6) Leakage is greater than specifications,

repair or replace steering unit.

73095SE09

5-25
5. STEERING UNIT PRESSURE TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed High idle
LS
Oil pressure 20.5~21.5 MPa
(205~215 bar, 3200±3300 psi) CF

· GAUGE AND TOOL

Gauge 0~35 MPa (0~350 bar, 0~5000 psi)
P
Temperature reader
1) Connect gauge to test port.
2) Install temperature reader (see installation
procedure in this group).
3) Install frame locking bar.
4) Heat hydraulic oil to specifications (see
hydraulic oil warm up procedure at page
6-49).
5) Run engine at specifications and turn
steering wheel rapidly hold approximately
22N (5 lb force) pressure on wheel with
frames locked.
※ If steering wheel is turned slowly, it will
continue to with the frames locked. Safety lock bar

This will give an incorrect pressure read-

ing.
If steering wheel continues to turn rapidly
Relief valve
with the frames locked, steering system
leakage is indicated.
6) Read pressure gauge. This is the steering
A
valve relief pressure. B

7) If pressure is not to specification, remove

the plug (A) from steering unit. Turn adjust-
Steering unit
ing screw (B) in relief cartridge using a hex
head screw (8mm) to adjust pressure.
If pressure cannot be adjusted to specifica-
tion, disassemble and inspect steering unit. 7309S5SE10

5-26
GROUP 4 DISASSEMBLY AND ASSEMBLY

1. STEERING UNIT
1) STRUCTURE

5
38 31
37 6
36
35 33
34 7

8
39 2
34
35 10
39 36
38 9
37 11
12
13
14

13
15
19
13
16
17

18

74095SE05

1 Dust seal ring 10 Cardan shaft 19 Screw

2 Housing, spool, sleeve 11 O-ring 31 Set of O-rings
3 Ball 12 Intermediate plate 33 Rolled pin
4 Thread bushing 13 O-ring 34 Screw
5 Roto glyd ring 14 Distributor plate 35 Shock valve
6 Bearing assembly 15 Gearwheel set 36 Spring
7 Ring 16 End cover 37 O-ring
8 Cross pin 17 Washer 38 Plug
9 Set of spring 18 Screw with pin 39 Housing, check valve

5-27
2) TOOLS
(1) Holding tool.

7405S STVLV38(1)

(2) Assembly tool for O-ring and kin-ring.

7405S STVLV38(2)

(3) Assembly tool for dust seal.

7405S STVLV38(3)

(4) Torque wrench 0-7.1 kgf·m (0-51.6 lb·ft).

13 mm socket spanner
12 mm screwdriver
6 mm screwdriver
2 mm screwdriver
Plastic hammer
Ratchet spanner

7405S STVLV38(4)

5-28
3) DISASSEMBLY
(1) Disassemble steering column from
steering unit and place the steering unit in
the holding tool. Screw out the screws in
the end cover (7-off-one rolled pin).

7405S STVLV39(1)

(2) Remove the end cover, sideways.

7405S STVLV39(2)

(3) Lift the gearwheel set with spacer bushing

(and spacer if fitted) off the unit. Take out
the two O-rings.

7405S STVLV39(3)

(4) Remove spacer bushing and spacer(if

fitted) from the gearwheel.

7405S STVLV39(4)

5-29
(5) Remove cardan shaft.

7405S STVLV40(1)

(6) Remove distributor plate.

7405S STVLV40(2)

(7) Remove O-ring.

7405S STVLV40(3)

(8) Lift off intermediate plate.

7405S STVLV40(4)

5-30
(9) Remove O-ring.

7405S STVLV41(1)

(10) Screw out the threaded bushing.

7405S STVLV41(2)

(11) Remove cross pin.

7405S STVLV41(3)

(12) Shake out the ball (Ø8.5 mm).

7405S STVLV41(4)

5-31
(13) Pull sleeve and spool out of the housing.

7405S STVLV42(1)

(14) Take ring, bearing races and needle

bearing from sleeve and spool. The outer
(thin) bearing race can sometimes "stick"
in the housing, therefore check that it has
come out.

7405S STVLV42(2)

(15) Carefully pull the spool out of the sleeve.

7405S STVLV42(3)

(16) Press the neutral position springs out of

their slots in the spool.

7405S STVLV42(4)

5-32
(17) Remove dust seal and O-ring.

7405S STVLV43(1)

(18) The steering unit is now completely

disassembled.

7405S STVLV43(2)

Cleaning
Clamp all parts carefully in Shellsol K or the
like.
Inspection an replacement
Replace all seals and washer. Check all
parts carefully and make any replacements
necessary.
Lubrication
Before assembly, lubricate all parts with
hydraulic oil.

5-33
4) ASSEMBLY
(1) Assemble spool and sleeve.
※ The sleeve and spool are correctly B A
assembled when
① The slots-in sleeve and spool-for the
neutral position springs are opposite
each other and
② One of the 3 T-shaped grooves (A) in the
spool is opposite one of the sets (B) of
7405S STVLV44(1)
small holes in the sleeve.

(2) Place the two flat neutral position springs

in the slot.

7405S STVLV44(2)

(3) Place the curved springs between the flat

ones and press them into place.

7405S STVLV44(3)

(4) Line up the spring set.

7405S STVLV44(4)

5-34
(5) Guide the spool into the sleeve.

7405S STVLV45(1)

(6) Press the springs together and push the

neutral position springs into place in the
sleeve.

7405S STVLV45(2)

(7) Line up the springs and center them.

7405S STVLV45(3)

(8) Guide the ring down over the sleeve.

※ The ring should be able to rotate-free of
the springs.

7405S STVLV45(4)

5-35
 (9) Fit the cross pin into the spool/sleeve.

7405S STVLV46(1)

(10) Fit bearing races and needle bearing as

shown on below drawing.

7405S STVLV46(2)

1 Outer bearing race

1
2 Needle bearing
2
3 Inner bearing race
3
4 Spool
5 Sleeve *
Inside chamfer on inner bearing race 4
* must face inner spool.
5

7405S STVLV46(3)

(11) Grease O-ring and kin-ring with hydraulic

oil and place them on the tool. See next
page.

7405S STVLV46(4)

5-36
 7405S STVLV47(1)

(12) Put the steering unit in the holding tool

keeping the bore vertical. Guide the outer
part of the assembly tool into the bore.
Guide the inner part of the tool right to the
bottom.

7405S STVLV47(2)

(13) Press and turn the O-ring into position in

the housing. Draw the inner and outer
parts of the assembly tool out of the
steering unit bore, leaving the guide in the
bore.

7405S STVLV47(3)

(14) Take the steering unit out of the holding

tool and place it horizontally. With a light
turning movement, guide the spool and
sleeve into the bore.

7405S STVLV47(4)

5-37
(15) The spool set will push out the assembly
tool guide. The O-ring is now in position.

7405S STVLV48(1)

(16) Put the steering unit back into the holding

tool keeping the bore vertical. Place the
cross pin in the spool/sleeve so that it is
parallel to the port flange.

7405S STVLV48(2)

(17) Put the ball into the hole indicated by the

arrow.

7405S STVLV48(3)

(18) Screw the threaded bushing lightly into

the bore. The top of the bushing must lie
just below the surface of the housing.

7405S STVLV48(4)

5-38
(19) Grease the O-ring with mineral oil
approximate viscosity 500 cSt at 20 ˚C
and place it in the groove.

7405S STVLV49(1)

(20) Place the intermediate plate so that the

channel holes match the holes in the
housing.

7405S STVLV49(2)

(21) Grease the O-ring with mineral oil

approximate viscosity 500 cSt at 20 ˚C
and place it in the groove.

7405S STVLV49(3)

(22) Place the distributor plate so that the

channel holes match the holes in the
intermediate plate and the housing.

7405S STVLV49(4)

5-39
(23) Guide the cardan shaft down into the bore
so that the slot is parallel with the
connection flange.

7405S STVLV50(1)

(24) Place the gear wheel (rotor) so that the

cross pin from item 33 is positioned in
relation to two tooth bases - as the screw
driver indicates.

7405S STVLV50(2)

(25) Grease the two O-rings with mineral oil

approximate viscosity 500 cSt at 20 ˚C
and place them in the two grooves in the
gear rim. Fit the gear rim so that the
seven through holes match the holes in
the distributor plate.
※ Turn the gear rim so that the smaller
diameter of the holes face the distributor
plate.
7405S STVLV50(3)

(26) Orientate the holes with a single screw.

7405S STVLV50(4)

5-40
(27) Place the end cover in position.

7405S STVLV51(3)

(28) Place the washers over the holes and the

rolled pin in the hole shown.

7405S STVLV51(4)

(29) Fit the other six screws. Cross - tighten all

the screws and the rolled pin with a
torque of 3 ±0 . 6 kgf·m(22 ±4 . 4 lb·ft).
Steering unit can now be function tested.

7405S STVLV52(1)

(30) Turn the steering unit 180˚ and place the

dust seal ring in the housing.

7405S STVLV52(2)

5-41
(31) Fit the dust seal ring in the housing using
special tool and a plastic hammer.

7405S STVLV52(3)

(32) Press the plastic plugs into the connection

ports. Do not use a hammer.

7405S STVLV52(4)

5-42
2. VALVE BLOCK
1) STRUCTURE

31

33
38
37
36
35

39

34
35
39 36
37
38

P,T,L,R port PF 1/2

Shock valves 270-290 bar

7407SE12

31 Set of springs 36 Spring

33 Rolled pin 37 O-ring
34 Screw 38 Plug
35 Shock valve 39 Housing and check valve

5-43
2) TOOLS
(1) Hexagon socket spanner, 8 mm.

7405S OVLOAD63(1)

(2) Torque wrench, 0~7.1 kgf·m (0~51 lb·ft)

with 8 mm hexagon socket spanner.

7405S OVLOAD63(2)

(3) Adjustable wrench.

7405S OVLOAD63(3)

5-44
3) DISASSEMBLY
(1) Remove the rolled pin.

7405S OVLOAD64(1)

(2) Remove the plug (38) and O-ring (37).

838
737

7405S OVLOAD64(2)

(3) Remove the spring (36) and shock valve

(35). 6
36

35
5

7405S OVLOAD64(3)

(4) Remove the O-ring set (31).

1,2
31

7405S OVLOAD64(4)

5-45
(5) Remove the check valve (39).
39
9

7405S OVLOAD65(1)

(6) The overload valve is now disassembled.

7405S OVLOAD65(2)

5-46
4) ASSEMBLY
Cleaning
Clean all parts carefully in Shellsol K or the
like.
Inspection an replacement
Replace all seals and washers. Check all
parts carefully and make any replacements
necessary.
Lubrication
Before assembly, lubricate all parts with
hydraulic oil.

(1) Fit check valve (39).

9
39

7405S OVLOAD66(1)

(2) Fit the shock valve (35) and spring (36).

6
36

5
35

7405S OVLOAD66(2)

(3) Fit the O-ring (37) and screw the plug

(38). 8
38
37
7

7405S OVLOAD66(3)

5-47
(4) Fit the rolled pin.

7405S OVLOAD66(4)

(5) The overload valve is now assembled. It

can be checked for leakage separately or
when mounted on a steering unit.

7405S OVLOAD67(1)

(6) Locate the four O-rings between overload

valve and steering unit and fit these
components together.

7405S OVLOAD67(2)

(7) Tighten the hexagon socket screws with a

+3.6
torque of 6.6 +0.5
0 kgf·m(47.7 0 lb·ft).

7405S OVLOAD67(3)

5-48
 (8) Press the plastic plugs into the connection
por ts. The overload valve is now
assembled.

7405S OVLOAD67(4)

5) TROUBLESHOOTING
Problem Cause Remedy
Steering wheel 1. Over tighten mounting torque. Retighten as specified torque.
is heavy
2. Over load valve seat side is clogged Disassembly, clean, reassembly.
with dirt.
Steering cylinder 1. Overload valve seat side is clogged Disassembly, clean, reassembly.
reaction is bad with dirt.
2. Anti cavitation check valve seat is Disassembly, clean, reassembly.
clogged with dirt.
3. Damage of O-ring for adjusting. Replace.
Abnormal noise 1. Overload valve seat side clogged Disassembly, clean, reassembly.
with dirt.
Leakage 1. Loosen 2 mounting bolt. Retighten as specified torque.
2. Damage of O-ring. Replace.
3. Leakage through plug. Apply seal tape to thread and retighten
as specified torque.

5-49
3. PRIORITY VALVE
1) STRUCTURE

5
6
8

4
6

7309S5PR01

1 Plug 4 Spring 7 Orifice

2 Spool 5 Plug 8 Orifice
3 Nipple 6 O-ring

5-50
2) TOOLS
·Open-end spanner 22 mm.
·Nylon pin.
·Hexagon socket spanner 8 mm.
·Torque wrench.
·Socket spanner 22 mm.
·Hexagon socket spanner insert 8 mm.

7309S5PR02A

3) DISASSEMBLY
※ Cleanliness is the primary means of
assuring satisfactory the priority valve life.
Select clean place.
Before removing the piping, clean the
surrounding area of valve ports.

(1) Screw out the PP plug using the 8 mm

hexagon socket spanner.
Remove the seal ring.

PP

LS

7309S5PR02B

(2) Loosen the LS plug using the 22 mm

open-end spanner.

LS

7309S5PR02C

5-51
(3) Pull out the plug with seal ring and spring.

PP

LS

7309S5PR02D

(4) Press out the spool using the nylon pin.

PP

LS

7309S5PR03A

(5) Disassembled priority valve.

PP

LS

7309S5PR03B

5-52
4) MODIFICATION
(1) The control spring pressure can be altered by replacing the spring (See table below). Replace
name plate so that code no. and control spring pressure match each other again.

Control spring
d (mm) Di (mm) L (mm)
pressure (bar)
4 1.8 6.9 54
7 2.0 6.5 55 Di

d
L

7309S5PR03C

(2) Cleaning
Clean all parts carefully in low aromatic kerosene.
(3) Inspection and replacement
Check all parts carefully and make any replacements necessary. All seal rings must be replaced.
(4) Lubrication
Lubrication
Before assembly, lubricate all parts with hydraulic oil.

5) ASSEMBLY
(1) Guide the spool into the bore. Use the
nylon pin to center the spool in the bore.
PP

LS

7309S5PR04A

(2) Put in the PP plug.

Remember seal ring.

PP

LS

7309S5PR04B

5-53
(3) Guide the spring and LS plug into the
bore.
Remember seal ring.
PP

LS

7309S5PR02D

(4) Tighten the LS plug with torque wrench

using a 22 socket spanner insert.
·Tighten torque : 5.1±1 kgfㆍm
(36.9±7.2 lbfㆍft) PP

LS

7309S5PR04C

(5) Tighten the PP plug with a torque wrench

using a 8mm hexagon socket spanner
insert.
·Tighten torque : 5.1±1 kgfㆍm
(36.9±7.2 lbfㆍft)

7309S5PR05A

(6) The priority valve is now assembled.

7309S5PR05B

5-54
 6) TROUBLESHOOTING

Problem Cause Remedy

Steering wheel 1. Relief valve of steering unit is clogged Disassembly, clean and reassembly.
is heavy with dirt.
2. Spool is stuck. Disassembly, clean and reassembly or
replace.
3. Orifice of plug and spool is clogged. Disassembly, clean and reassembly.
(Steering wheel is heavy
a. Pump is faulty. Check pump.
at engine low idle)

(Steering speed b. Control pressure is low. Reset control pressure.

is not high at engine high c. Piping is faulty. Replace piping.
idle)
d. Pump is faulty. Check pump.
Abnormal noise 1. Relief valve of steering unit is clogged Disassembly, clean, reassembly.
with dirt.
2. Spool is stuck. Disassembly, clean and reassembly or
replace.
Leakage 1. Loosen the plug. Retighten the specified torque.
2. O-ring is damaged. Replace.

5-55
4. STEERING CYLINDER
1) STRUCTURE

3 5,4 12 7,6 8 11,10 9 2 1 13 16 14 15 17 25 24

22,23

19,20,21 18

73095SE07

1 Tube assy 10 O-ring 19 U-bolt

2 Rod assy 11 Back up ring 20 Hexagon nut
3 Gland 12 O-ring 21 Spring washer
4 Dust wiper 13 Piston 22 Bushing
5 Retaining ring 14 Piston seal 23 Dust seal
6 Rod seal 15 Wear ring 24 Spherical bearing
7 Back up ring 16 O-ring 25 Retaining ring
8 Step seal 17 Nylon nut
9 Du bushing 18 Pipe assy

5-56
 2) TOOLS AND TIGHTENING TORQUE
(1) Tools

Tool name Remark

14 B

Spanner 30
32
Steel bar For gland
(-) Driver Small and large sizes
Torque wrench Capable of tightening with the specified torques

(2) Tightening torque

Torque
Part name Item Size
kgf·m lbf·ft
Gland 3 M64 × 1.5 65 ± 7 463 ± 51
Piston 13 M24 × 2.0 40 ± 4 289 ± 28.9
Nut(Pipe assy) 18 M22 × 1.5 30 ± 3 217 ±21.7
Nut 20 M10 × 1.5 3.2 ± 0.3 23.1± 2.2

5-57
3) DISASSEMBLY
(1) Remove cylinder head and piston rod
① Hold the clevis section of the tube in a
vise.
※ Use mouth pieces so as not to damage
the machined surface of the cylinder
tube. Do not make use of the outside
piping as a locking means.

② Pull out piston rod (2) about 200 mm (7.1

in). Because the piston rod is rather
heavy, finish extending it with air
pressure after the oil draining operation. m
0m
20

7407ASE30

③ Loosen and remove the gland (3).

※ Cover the extracted piston rod (2) with
rag to prevent it from being accidentally
damaged during operation.

3
2

7407ASE31

④ Draw out gland (3) and piston rod (2)

assembly together from cylinder tube (1).
Lift
※ Since the piston rod assembly is heavy
in this case, lift the tip of the piston rod
(2) with a crane or some means and
draw it out. However, when piston rod
(2) has been drawn out to
approximately two thirds of its length, lift Full straight Oil pan
it in its center to draw it completely. sideways
7407ASE32

5-58
※ Note that the plated surface of piston rod
(2) is to be lifted. For this reason, do not
use a wire sling and others that may
damage it, but use a strong cloth belt or
a rope.

⑤ Place the removed piston rod assembly

on a wooden V-block that is set level.
※ Cover a V-block with soft rag.
Piston rod assy

Wooden block

7407ASE33

(2) Remove piston and gland assembly

① Remove the nylon nut (17). 16 14 15 13 17
② Remove piston assembly (13), and
O-ring (16).

73095SE34

④ Remove the gland (3) assembly from

piston rod (2). Lift with a crane
※ If it is too heavy to move, move it by
Plastic
striking the flanged part of gland (3) hammer 5,4 6,7 8 9
with a plastic hammer.
※ Pull it straight with cylinder head Full straight
assembly lifted with a crane.
Exercise care so as not to damage the
lip of rod bushing (9) and packing (4, 5, 3
6, 7, 8) by the threads of piston rod (2). 2
73095SE35

5-59
(3) Disassemble the piston assembly
① Remove wear ring (15) and piston seal 14 15
(14).
※ Exercise care in this operation not to
damage the grooves.

73095SE42

(4) Disassemble gland assembly

① Remove back up ring (11), and O-ring 5,4 12 7,6 8 11,10 9
(10).
② Remove O-ring (12).
③ Remove snap ring (5) and dust wiper (4).
④ Remove back up ring (7), rod seal (6).
⑤ Remove step seal (8).
※ Exercise care in this operation not to
damage the grooves.
73095SE43
※ Do not remove seal and ring, if does not
damaged.

5-60
4) ASSEMBLY
(1) Assemble gland assembly
※ Check for scratches or rough surfaces if
found smooth with an oil stone.
① Coat the inner face of gland (3) with
hydraulic oil.
3

7407ASE44

② Coat dust wiper (4) with grease and fit

Press here
dust wiper (4) to the bottom of the hole of (Straight down)
dust wiper.
At this time, press a pad metal to the 48 Metal
metal ring of dust seal.
③ Fit snap ring (5) to the stop face.

7407ASE45

④ Fit back up ring (7) and rod seal (6) to

corresponding grooves, in that order.
⑤ Fit step seal (8).
※ Coat each packing with hydraulic oil
Wrong Right
before fitting it.
※ Insert the backup ring until onside of it is
inserted into groove.

7577ASE42

※ Rod seal (6) has its own fitting direction.

Therefore, confirm it before fitting them. Push bar
※ Fitting rod seal (6) and step seal (8) up
side down may damage its lip. Therefore
check the correct direction that is shown
in fig.
8
7,6

73095SE46

5-61
 ⑥ Fit back up ring (11) to gland (3).
※ Put the backup ring in the warm water of 9
30~50˚C.
10
⑦ Fit O-ring (10) to gland (3).
⑧ Fit bushing (9) to gland (3). 11
3
12

73095SE47

(2) Assemble piston assembly

※ Check for scratches or rough surfaces.
If found smooth with an oil stone.
① Coat the outer face of piston (13) with
hydraulic oil. 13

73095SE36

② Fit piston seal (15) to piston

※ Put the piston seal in the warm water of
60~100˚C for more than 5 minutes. 15
※ After assembling the piston seal, press
its outer diameter to fit in.

7407ASE48

③ Fit wear ring (15) to piston (13).

④ Fit O-ring (16) to piston (13). 16 14 15 13

73095SE49

5-62
(3) Install piston and gland assembly
① Fix the piston rod assembly to the work Gland assembly Piston rod
bench.
② Apply hydraulic oil to the outer surface of
piston rod (2), the inner surface of piston
and gland.
③ Insert gland assembly to piston rod (2).

73095SE37

④ Fit piston assembly to piston rod.

Piston assembly
Piston rod

73095SE38

⑤ Tighten nylon nut(17) to piston rod(2).

·Tightening torque : 40±4 kgf·m 2 17
(289±28.9 lbf·ft)

73095SE39

5-63
(4) Overall assemble
① Place a V-block on a rigid work bench. Fix with a bar

Mount the cylinder tube assembly (1) on Lift

it and fix the assembly by passing a bar
through the clevis pin hole to lock the
assembly.
② Insert the piston rod assembly in to the Straight
cylinder tube assembly, while lifting and
moving the piston rod assembly with a Apply liquid packing
7407ASE40
crane.
※ Be careful not to damage piston seal by
thread of cylinder tube.
③ Fit gland to the tube.
·Tightening torque : 65 ±7kgf·m
(463 ± 51lbf·ft)

7407ASE41

5-64
5. CENTER PIVOT PIN
1) CONSTRUCTION
Figure shows the construction of the center pivot pin assembly. This assembly serves to connect
the front frame with the rear frame; two sets of assemblies are provided, one each for the upper
and lower parts. The numbers in parentheses following the parts name denote the item numbers
shown in the figure in the disassembly and assembly procedures.

24 23 11 16 8 7 12 17

13 14,15 14,15

26
26 2
4,5,6

25 25

3 1 18
1
9
10
19,20,21
22
UPPER LOWER

73095SE13

1 Bearing 10 Plate 19 Shim (0.1 t)

2 Cover 11 Pin 20 Shim (0.5 t)
3 Cover 12 Dust seal 21 Shim (2.0 t)
4 Shim (0.1 t) 13 Dust seal 22 Hexagon bolt with washer
5 Shim (0.5 t) 14 Hexagon bolt 23 Hexagon bolt
6 Shim (1.0 t) 15 Hardened washer 24 Hardened washer
7 Pin 16 Bushing 25 Front frame
8 Collar 17 Cover 26 Rear frame
9 Collar 18 Cover

5-65
2) DISASSEMBLY
After supporting the front frame and the
rear frame as horizontally as possible using
wood blocks and jacks, disassemble as
fo l l o w s : I n o r d e r t o fa c i l i t a t e t h e
disassembly/assembly of the center pivot
pins, remove the drive shaft, hydraulic line
and steering cylinder first.
(1) Maintain the horizontal level of front frame
(25) and rear frame (26), and then UPPER
remove hexagon bolt (23), washer (24).
24 23 11
(2) Take out upper pin (11) to the upside
using a metal punch.

26

25

73095SE14

(3) Maintain the front frame horizontal level,

LOWER 7
remove hexagon bolts (22) and then
remove the plate (10) and shims (19, 20,
21).
26
(4) Take out lower pin (7) to the upside using
a metal punch carefully.
25
(5) Jack up or lifting the front frame (25)
slightly, the collar (9) protrudes over the
9
rear frame.
Remove the collar (9). 10
19,20,21
(6) Lift the frame by passing the slinging wire
rope at four positions of front frame, in 22
73095SE15

order to separate it from the rear frame.

(7) Support the front frame safely.

5-66
 (8) Remove bolt (14), washer (15) and then
UPPER
take out cover (2) and shims (4, 5, 6).
14,15 13 2
(9) Take out dust seal (13) from the cover (2).
(10) Remove the bearing (1), and dust seal 4,5,6
(13). 25

13
73095SE16

(11) Remove bolt (14), washer (15) and then

LOWER
take out cover (17, 18) and shims (4, 5, 6).
14,15 8 12 17
(12) Take out the dust seal (12) from the cover
(17, 18).
4,5,6
(13) Remove the bearing (1) and collar (8). 25

12 18
73095SE19

3) INSPECTION
(1) Check the bearing sliding surface for excessive wear, scorching or scratches; replace if
necessary.
(2) Replace all dust seals (12,13) with new ones.
(3) Grind any pins (7, 11) dented with an oilstone or replace any pins abrasive excessively.
(4) Check inside cover (2, 3, 17, 18) and collar (8, 9) for dents or scratches; if any damage is found,
correct with a grinder or replace.
(5) The serviceable limit of pins and bushings is shown in the table below. Unit : mm

Std Serviceable limit

Item No. Name Remedy
dimension Outer dia Inner dia Clearance
7, 11 Pin 59.5 -
1 Tapered roller bearing 60 - 60.5 0.8 Replace
8, 9 Collar - 60.5
12, 13 Dust seal When removed Replace

5-67
 4) ASSEMBLY

24 23 11 16 8 7 12 17

13 14,15 14,15

26
26 2
4,5,6
Clearance A
25
25
3 1 18
1
9
10
19,20,21
Clearance B
UPPER LOWER 22

73095SE20

Assemble the center pivot group by reversing the order of disassembly while paying close attention
to the following.
(1) Put the dust seal (12,13) into cover (2, 3, 17, 18).
※ Apply grease to the lip of the dust seal. Insert the dust seal so that the dust seal lip faces out and
punch four places on the outer circumference of the seal to lock it.
(2) Lower the temperature of the lower bearing cup to -75±5˚C (-103±9˚F ) and install it to front
frame until it contacts the bottom of the frame.
(3) Place the cover (3, 18).
(4) Coat lightly with oil and install lower bearing in bore in front frame. Coat lightly with oil and install
upper bearing in bore in upper front frame.
(5) Place the cover (2, 17) and hold in place with bolt (14). At this time, adjust shims (4, 5, 6) to press
the shoulder of bearing (1) against retainer.
ㆍ Adjustment method of clearance A
① Install bearing (1) and cover (2, 17) without shim (4, 5, 6)
Install four of bolt (14) so that each bolt is separated by 90 degrees.
ㆍTightening torque : 0.8~1.0 kgfㆍm (5.8~7.2 lbfㆍft)
② Adjust shims (4, 5, 6) in order to control the clearance A.
ㆍClearance A : Below 0.1 mm
ㆍShim thickness : 0.1 mm, 0.5 mm, 1.0 mm

5-68
 (5) Apply grease to lower collar (8) and insert it to the lower of roller bearing.
(6) After setting the bearing so that its upper surface is horizontal, tighten the all the bolt (14).
After tightening, confirm that tapered roller bearing moves lightly ; if does not move smoothly, add
shims (4, 5).
ㆍ Bearing preload : 0.3~0.9 kgfㆍm
ㆍ Tightening Torque : 9.8~15.8 kgfㆍm (70.9~114 lbfㆍft)
ㆍ Apply loctite #243.
(7) Move the front frame and join it to the rear frame so that match the pin hole at the center.
(8) Apply grease to pin (11), bushing (16) and insert it into tapered roller bearing (1).
(9) Apply grease to lower collar (9) and insert it to the lower of roller bearing through rear frame (26).
(10) Apply grease to pin (7) and insert it into tapered roller bearing (1).
(11) Before tightening bolt (22), adjust shims (19, 20, 21) in order to control the clearance between the
plate (10) and rear frame (26).
ㆍAdjustment
Adjustment method of clearance B
① Install pin (7) and plate (10) without shim (19, 20, 21).
Install four of bolt (22) so that each bolt is separated by 90 degrees.
ㆍTighting torque : 0.8~1.0 kgfㆍm (5.8~7.2 lbfㆍft)
② Adjust shims in order to control the clearance B.
ㆍClearance B : 0.1~0.2 mm
ㆍShim thickness : 0.1 mm, 0.5 mm, 2.0 mm
(12) Tighten the all the bolts (22).
ㆍTightening Torque : 9.8~15.8 kgfㆍm (70.9~114 lbfㆍft)
ㆍApply loctite #243.

5) TROUBLESHOOTING
Trouble Probable cause Remed
Capscrew for fixing steering valve is loose Retighten
Faulty center pivot pin mounting bolts Retighten
Shock is felt when steering
Center pivot pins have worn out Readjust or replace
Faulty hydraulic system See hydraulic system
Fault fixing of connecting capscrews Retighten
Center pins have worn out Readjust or replace
Shock is felt when moving
Bearings of support unit have worn out Retighten
backward or forward
Drive shaft damaged See drive system
Faulty transmission See transmission system

5-69
 SECTION 6 WORK EQUIPMENT

Group 1 Structure and Function ----------------------------------------------------------------------------------- 6-1

Group 2 Operational Checks and Troubleshooting ----------------------------------------------------- 6-35
Group 3 Tests and Adjustments ----------------------------------------------------------------------------------- 6-45
Group 4 Disassembly and Assembly --------------------------------------------------------------------------- 6-60
 SECTION 6 WORK EQUIPMENT
GROUP 1 STRUCTURE AND FUNCTION

1. HYDRAULIC SYSTEM OUTLINE

The loader hydraulic system is a pilot operated, open center system which is supplied with flow from
the fixed displacement main hydraulic pump.
The polit control system is a low pressure, closed center hydraulic system which is supplied with flow
from the first(steering) pump.
The loader system components are :
·Main pump
·Main control valve
·Bucket cylinder
·Boom cylinders
·Pilot supply unit
·Remote control valve (Pilot control valve)
·Safety valve

The pilot supply unit consists of the pressure reducing valve, relief valve and accumulator.
Flow from the main hydraulic pump not used by the steering system leaves the priority valve EF port.
It flows to the inlet port plate of four blocks type main control valve.
The main control valve is open center system which routes flow to the boom, bucket or auxiliary
cylinders (not shown) when the respective spools are shifted.
Flow from the steering pump is routed to the pilot supply unit where the steering pump outlet
pressure is reduced to pilot circuit pressure. The pilot supply unit control valve flow to the remote
control valve.
The remote control valve routed flow to either end of each spool valve section in the main control
valve to control spool stroke.
A accumulator mounted on pilot supply unit supplies a secondary pressure source to operated
remote control valve so the boom can be lowered if the engine is off.
The return circuit for the main hydraulic system have return filter inside the hydraulic tank. The return
filter uses a filter element and a bypass valve. The bypass valve is located in the upside of filter.

6-1
 2. HYDRAULIC CIRCUIT

32
T X
10 11 12 31
FRONT REAR
4
B.D/F B.U IN OUT

L.H R.H L.H R.H

34 B A T
P
1 3 4 2 5 6
18 PS
BL1 BR1 BL2 BR2
3 T
8
T1 P1 T2 P2 3B
3A

5 a3 BOOM UP BOOM DOWN

b3
33

PS
17 17 L FLOATING

27
7 A1 A2
2B
T
19 2A
15
PS

R DUMP ROLL BACK

PS a2 b2
P
P1

T1 T F2
1B
A3 14
16 P 1A

B a1
AUX.
b1
LS
13P2 F1

PS1
PS

19 CF EF U
P T 6 P

20 LS
P1 T
P

2 1
30
PS

M1
A
P1 23
30 M2
PS

29 T P
P2 24 21 C
28 25 26
M 22

7309S6WE01

1 Main pump 13 Pilot supply unit 24 Hydraulic tank

2 Fan & brake pump 14 Line filter 25 Return filter
3 Main control valve 15 Safety valve 26 Bypass valve
4 Remote control valve 16 Accumulator 27 Shockless valve
5 Steering unit 17 Accumulator 28 Pump motor (opt)
6 Priority valve 18 Pressure sensor 29 Check valve (opt)
7 Cut off valve 19 Pressure sensor 30 Pressure sensor (opt)
8 Brake valve 20 Line filter 31 Ride control valve (opt)
10 Steering cylinder 21 Oil cooler 32 Accumulator (opt)
11 Bucket cylinder 22 Fan motor 33 Pressure sensor (opt)
12 Boom cylinder 23 Air breather 34 Cushion valve

6-2
3. WORK EQUIPMENT HYDRAULIC CIRCUIT

11 12
4 B.D/F B.U IN OUT

LH RH
3 T T
P
1 3 4 2 5 6
3B

3A
BOOM
a3 BOOM UP DOWN b3
27
FLOATING
15 T

2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 21 22

Parking brake solenoid

7409S6WE02

1 Main pump 13 Pilot supply unit 23 Air breather

3 Main control valve 14 Line filter 24 Hydraulic tank
4 Remote control valve 15 Safety valve 25 Return filter
11 Bucket cylinder 21 Oil cooler 26 Bypass valve
12 Boom cylinder 22 Fan motor 27 Shockless valve

6-3
1) WHEN THE RCV LEVER IS IN THE RAISE POSITION

11 12
4 B.D/F B.U IN OUT

LH RH
3 T T
P
1 3 4 2 5 6
3B

3A
BOOM
a3 BOOM UP DOWN b3
27
FLOATING
15 T
Load check valve
2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 22
21

Parking brake solenoid

7409S6WE03

· When the RCV lever (4) is pulled back, the boom spool is moved to raise position by pilot oil
pressure from port 3 of RCV through shockless valve (27).
· The oil from main pump (1) flows into main control valve (3) and then goes to the large chamber of
boom cylinder (12) by pushing the load check valve of the boom spool.
· The oil from the small chamber of boom cylinder (12) returns to hydraulic oil tank (24) through the
boom spool at the same time.
· When this happens, the boom goes up.

6-4
2) WHEN THE RCV LEVER IS IN THE LOWER POSITION

11 12
4 B.D/F B.U IN OUT

3 Check valve T T
LH RH
P
1 3 4 2 5 6
3B

3A
BOOM
a3 BOOM UP DOWN b3
27
FLOATING 39 15 T

2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 21 22

Parking brake solenoid

7409S6WE04

· When the RCV lever (4) is pushed forward, the boom spool is moved to lower position by pilot
pressure from port 1 of RCV through orifice connector (39).
· The oil from main pump (1) flows into main control valve (3) and then goes to small chamber of
boom cylinder (12) by pushing the load check valve of the boom spool.
· The oil returned from large chamber of boom cylinder (12) returns to hydraulic tank (24) through
the boom spool at the same time.
· When the lowering speed of boom is faster, the return oil from the large chamber of boom cylinder
combines with the oil from the pump through the check valve, and flows into the small chamber of
the cylinder.
This prevents cylinder cavitation by the negative pressure when the pump flow cannot match the
boom down speed.

6-5
3) WHEN THE RCV LEVER IS IN THE FLOAT POSITION

11 12
4 B.D/F B.U IN OUT

LH RH
3 T T
P
1 3 4 2 5 6
3B

3A
a3 BOOM UP b3
27 BOOM DOWN FLOATING
15 T

2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 21 22

Parking brake solenoid

7409S6WE05

· When the RCV lever (4) is pushed further forward from the lower position, the pilot pressure
reaches to 13~15bar, then the boom spool is moved to floating position.
· The work ports (3A), (3B) and the small chamber and the large chamber are connected to the
return passage, so the boom will be lowered due to it's own weight.
· In this condition, when the bucket is in contact with the ground, it can be move up and down in
accordance with the shape of the ground.

6-6
4) WHEN THE RCV LEVER IS IN THE DUMP POSITION

11 12
4 B.D/F B.U IN OUT

3 T T
LH RH
P
1 3 4 2 5 6
3B

3A
BOOM
a3 BOOM UP DOWN b3
27
FLOATING
15 T

2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 21 22

Parking brake solenoid

7409S6WE06

· If the RCV lever (4) is pushed right, the bucket spool is moved to dump position by pilot oil pressure
from port 2 of RCV.
· The oil from main pump (1) flows into main control valve (3) and then goes to the small chamber of
bucket cylinder (11) by pushing the load check valve of the bucket spool.
· The oil at the large chamber of bucket cylinder (11) returns to hydraulic tank (24).
· When this happens, the bucket is dumped.
· When the dumping speed of bucket is faster, the oil returned from the large chamber of bucket
cylinder combines with the oil from the pump, and flows into the small chamber of the cylinder.
This prevents cylinder cavitation by the negative pressure when the pump flow cannot match the
bucket dump speed.

6-7
5) WHEN THE RCV LEVER IS IN THE ROLL BACK (retract) POSITION

11 12
4 B.D/F B.U IN OUT

LH RH
3 T T
P
1 3 4 2 5 6
3B

3A
BOOM
a3 BOOM UP DOWN b3
27
FLOATING
15 T

2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 21 22

Parking brake solenoid

7409S6WE07

· If the RCV lever (4) is pulled left, the bucket spool is moved to roll back position by pilot oil pressure
from port 4 of RCV.
· The oil from main pump (1) flows into main control valve (3) and then goes to the large chamber of
bucket cylinder by pushing the load check valve of the bucket spool.
· The oil at the chamber of bucket cylinder (11) returns to hydraulic tank (24).
· When this happens, the bucket roll back.

6-8
6) WHEN THE RCV LEVER IS IN THE HOLD POSITION

11 12
4 B.D/F B.U IN OUT

LH RH
3 T T
P
1 3 4 2 5 6
3B

3A
BOOM
a3 BOOM UP DOWN b3
27
FLOATING
15 T

2B

2A P
DUMP ROLL BACK
a2 b2
F2
14
1B

1A
F1
a1
AUX
b1
P2 13

P
P1 T
Priority valve EF port
Steering system
Brake system
1
Return line

23

24
T P

25 26 21 22

Parking brake solenoid

7409S6WE08

· The oil from main pump (1) flows into main control valve (3)
· In this time, the bucket spool, the boom spool and the boom float spool are in neutral position, then
the oil supplied to main control valve (3) returns into hydraulic tank (24) through center bypass
circuit of each spool.
· In this condition, each cylinder keeps the neutral position, so the boom and the bucket is holded.

6-9
4. MAIN PUMP
1) STRUCTURE

6 1 2 8 3 4 5 7

10 11,12 13 9 14

15,16 17

S1

P1 P2

Port Port name Port size

P1 Pressure port (to steering valve) 1" split flange
P2 Pressure port (to MCV) 1" split flange
S1 Suction port 2" split flange
7309S6WE29

1 Cover 7 Driven gear set 13 Square seal

2 Housing 8 Connecting shaft 14 Dowel pin
3 Carrier 9 Thrust plate 15 Washer
4 Housing 10 Lip seal 16 Hexagon nut
5 Cover 11 Rubber seal 17 Stud bolt
6 Drive gear set 12 Back up seal

6-10
2) OPERATION
The main hydraulic pump is a fixed displacement gear type pump. The pump is driven at engine
speed by the transmission. The pump shafts are supported by lip seal (10), front cover (1), housing
(2, 4) and rear cover (5). The thrust plate (9) are located between the gear surface and front cover
(1), housing (2, 4) and rear cover (5).

As the drive gear (6) turns the driven gears (7), the gear teeth come out of mesh. Oil flows from the
hydraulic tank through the inlet into the cavity between the gear teeth. As the gears continue to
rotate, the oil becomes trapped between the gear teeth and housing (2, 4).
The trapped oil is then carried to the pump outlet. Oil is forced out the outlet to supply the hydraulic
function. As the gears re-mesh, they form a seal to prevent oil from flowing between the gears and
back to the inlet.

The pump uses outlet pressure oil to load the thrust plate (9) against the gear faces. This controls
internal leakage to maintain pump displacement.
Outlet pressure fills the area bounded by the pressure balance moulded seals (13) to force the
thrust plate against the high pressure area or the gear faces.

6-11
5. REMOTE CONTROL VALVE
1) STRUCTURE

38
37
36
33
32
34
35
23
27
26 28
25 30
24 29
19 31
21 20
22 18
17
8
5 16
9 14
12
15
11
10 13
4
7 PF 1/4
49
6
3 47
2 48
UNC 9/16
1,46
39,40,41,42
45

41,42,43,44 7407S6WE28

1 Body 14 Rod seal 27 Nut 40 Rear holder

2 O-ring 15 O-ring 28 Plug 41 Terminal
3 Plug 16 Push rod 29 Nut 42 Seal wire
4 Spring 17 Plate 30 Set screw 43 Housing
5 Spring seat 18 Rod stopper 31 Nut 44 Rear holder
6 Spool 19 Bushing 32 Nut 45 Clip band
7 Spring seat 20 Rod 33 Handle bar 46 Plug
8 Stopper 21 Magnet 34 Nut 47 Connector
9 Spring 22 Plate 35 Boot 48 O-ring
10 Spring seat 23 Joint assy 36 Handle assy 49 O-ring
11 Spring 24 Joint assy 37 Nut
12 Spring seat 25 Plate 38 Spring washer
13 Plug 26 Washer 39 Housing

6-12
2) OPERATION

T P

B.D/F B.U IN OUT

1 34 2
HYDRAULIC CIRCUIT
(3 Electromagnetic locks) 36
38

35

24 20

21

(1) Hydraulic functional principle 16

4
Pilot devices with end position locks operate as
direct operated pressure reducing valves. 9
They basically comprise of handle (36), four
pressure reducing valves, body (1) and locks. 6
Each pressure reducing valve comprises of a
1
control spool (6), a control spring (9), a return
spring (4), push rod (16) and rod (20).
At rest, handle (36) is held in its neutral position by
return springs (4). Ports (1, 2, 3, 4) are connected 7407S6WE27

to tank port T via drilling.

When handle (36) is deflected, rod (20) is pressed against return spring (4) and control spring (9).
Control spring (9) initially moves control spool (6) downwards and closes the connection between
the relevant port and tank port T. At the same time the relevant port is connected to port P via
drilling. The control phase starts as soon as control spool (6) finds its balance between the force
from control spring (9) and the force, which results from the hydraulic pressure in the relevant port
(ports 1, 2, 3 or 4).
Due to the interaction between control spool (6) and control spring (9) the pressure in the relevant
port is proportional to the stroke of rod (20) and hence to the position of handle (36).
This pressure control which is dependent on the position of the handle (36) and the
characteristics of the control spring permits the proportional hydraulic control of the main
directional valves and high response valves for hydraulic pumps.
A rubber boot (35) protects the mechanical components in the housing from contamination.

6-13
(2) End position lock
Only those control ports, for which it is necessary to hold the handle in a deflected position are
equipped with end position locks.
Electromagnetic lock
When this threshold is overcome, a joint assy (24) contacts the magnet (21); if the magnet (21) is
energized, then handle (36) is held in its end position by magnetic force.
This lock is released automatically when the solenoid is deenergized.

6-14
6. MAIN CONTROL VALVE
1) STRUCTURE

20

19 1
39
11 6 40
21-1
4 6-1 38
23 3 34 36
25 35
30
24
21
8
16
5 8
33
18 8 11
1 37 9 29
32
22
21-1 13
8 31
26
2-1 28 13
2 14
40 21 4
12 19
27
12 15
14
4

19

10 20

7407B6WE45

1 Nut 14 Screw 28 Spool

2 Plug 15 Screw 29 Spool
2-1 O-ring 16 Anti void assy 30 Spring
3 O-ring 18 Spool cap 31 Spring
4 O-ring 19 Spool cap 32 Back up ring
5 Cap screw 20 Cap screw 33 Inlet section assy
6 Plug 21 Spool retainer 34 Spool section assy
6-1 O-ring 21-1 Back up ring 35 Spool section assy
8 O-ring 22 Spool retainer 36 Outlet section assy
9 Spring 23 Screw 37 Poppet
10 Main relief valve 24 Washer 38 Tie rod
11 Port relief valve 25 Spacer 39 Tie rod
12 Spring seat 26 Spring 40 Nut
13 Washer 27 Spring

6-15
STRUCTURE

A1 A2 A3
P

B1 B2 B3

3B

3A
BOOM
BOOM UP DOWN
a3 b3

FLOATING

2B

2A
DUMP ROLL BACK
a2 b2

1B

1A
AUX
a1 b1

b1(a1) b2(a2) b3(a3)

P

HYDRAULIC CIRCUIT
7407B6WE20

Port Port name Port size

P From main pump 1 3/16 - 12UN
T To hydraulic tank 1 5/16 - 12UN
A1, B1 To auxiliary cylinder port 1 3/16 - 12UN
A2, B2 To bucket cylinder port 1 3/16 - 12UN
A3, B3 To boom cylinder port 1 3/16 - 12UN
a3, b3 Boom pilot port 9/16 - 18 UNF
a2, b2 Bucket pilot port 9/16 - 18 UNF
a1, b1 Auxiliary pilot port 9/16 - 18 UNF

6-16
 2) BOOM SECTION OPERATION
(1) Spool in neutral

3B

3A

24Mpa BOOM UP BOOM DOWN

a3 b3

FLOATING
24Mpa

2B

2A

24Mpa DUMP ROLL BACK

a2 b2

3A 3B

a3 b3

Low pressure passage

7407B6WE11

If the remote control valve is not operated, the oil supplied from the pump port passes through the
neutral passage to the low pressure passage at the outlet section, and then returns to the tank port.

6-17
 (2) Boom raise position

3B

3A

24Mpa BOOM UP
a3 b3

24Mpa

2B
2A

24Mpa DUMP ROLL BACK

a2 b2

Load check valve(1)

SECTION A-A

3A 3B

A A

a3
b3

Low pressure passage

7407B6WE12

When the pilot pressure from remote control valve is supplied to the pilot port (a3), the spool moves to
the right and the neutral passage is closed.
The oil supplied from the pump pushes up the load check valve (1) and flow into boom cylinder port
(3A).
The pump pressure reaches proportionally the load of cylinder and fine control finished by shut off of
the neutral passage.
The return oil from cylinder port (3B) flows into the tank via the low pressure passage.

6-18
 (3) Boom lower position
Check valve(2)
T

3B

3A

24Mpa BOOM DOWN

a3 b3

24Mpa

2B
2A

24Mpa DUMP ROLL BACK

a2 b2

Load check valve(1)

SECTION A-A

3A 3B

A A

b3
a3

Low pressure passage

7407B6WE13

When the pilot pressure from remote control valve is supplied to the pilot port (b3), the spool moves to
the left and the neutral passage is closed.
The oil supplied from the pump pushes up the load check valve (1) and flow into boom cylinder port
(3B). The pump pressure reaches proportionally the load of cylinder and fine control finished by shut off
of the neutral passage.
The return oil from cylinder port (3A) flows into the tank via the low pressure passage.
When the lowering speed of boom is faster, the return oil from the large chamber of boom cylinder
combines with the oil from the pump through the check valve (2), and flows into the small chamber of
cylinder. This prevents cylinder cavitation by the negative pressure when the pump flow cannot match
the boom lowering speed.

6-19
 (4) Boom float position

3B

3A

24Mpa FLOATING
a3 b3

24Mpa

2B
2A

24Mpa DUMP ROLL BACK

a2 b2

3A 3B

b3
a3

Low pressure passage

7407B6WE14

If the remote control lever pushes further more, the pilot pressure from remote control valve rises over
13-15bar and then the boom lowering spool is pushed to the boom floating position, opening up the
neutral passage to tank and simultaneously (3A), (3B) → T.
In float position the boom drops quickly due to its own weight.
When the bucket touches the ground and the wheeled loader is moving, the bucket raised or lowered
following the unevenness of the ground due to the (3A), (3B) → T connecting.

6-20
3) BUCKET SECTION OPERATION
(1) Spool in neutral

24Mpa

2B

2A

24Mpa DUMP ROLL BACK

a2 b2

21Mpa

2A 2B

a2 b2

Low pressure passage

7407B6WE15

If the remote control valve is not operated, the oil supplied from the pump port passage through the
neutral passage to the low pressure passage at the outlet section, and then return to the tank port.

6-21
 (2) Retract (roll back) position

24Mpa

2B

2A

24Mpa ROLL BACK

a2 b2

Load check valve(1)

21Mpa

SECTION A-A
2A 2B

A A

b2
a2

Low pressure passage

7407B6WE16

When the pilot pressure from remote control valve is supplied to the pilot port (b2), the spool moves to
the left and the neutral passage is closed.
The oil supplied from the pump pushes up the load check valve (1) and flow into bucket cylinder port
(2B).
The pump pressure reaches proportionally the load of cylinder and fine control finished by shut off of
the neutral passage.
The return oil from cylinder port (2A) flows into the tank via the low pressure passage.

6-22
(3) Dump position

24Mpa

2B

2A

24Mpa DUMP
a2 b2

Load check valve(1)

21Mpa

SECTION A-A
2A 2B

A A

a2
b2

Low pressure passage

7407B6WE17

When the pilot pressure from remote control valve is supplied to the pilot port (a1), the spool
moves to the right and the neutral passage is closed.
The oil supplied from the pump pushes up the load check valve (1) and flow into bucket cylinder
port (2A).
The pump pressure reaches proportionally the load of cylinder and fine control finished by shut off
of the neutral passage.
The return oil from cylinder port (2B) flows into the tank via the low pressure passage.

6-23
4) PRESSURE SETTING

A good pressure gage must be installed in Relief valve Check valve Pilot section
poppet(D) poppet(K)
the line which is in communication with the
Pilot poppet(E) Lock nut
work port relief. A load must be applied in
a manner to reach the set pressure of the
relief unit.

(1) Main relief valve

① Loosen lock nut.
② Set adjusting nut to desired pressure Piston poppet(C) Housing O-ring
setting. Piston spring Pilot spring Adjust nut
③ If desired pressure setting cannot be
achieved, add or remove shims as
required. T
④ Tighten lock nut. 210 bar
220bar
⑤ Retest in similar manner as above.
P

7407AWE50

(2) Port relief valve

① Loosen lock nut.
Relief valve Check valve Pilot section
② Set adjusting screw to desired pressure poppet(D) poppet(K)
setting. Pilot poppet(E) Lock nut
③ Tighten lock nut.
④ Retest in similar manner as above.

Piston poppet(C) Pilot spring O-ring

Piston spring Housing Adjust screw

T
240bar

7407AWE51

6-24
5) MAIN RELIEF VALVE
(1) As relief
A D B K
The relief valve is in communication
between the high pressure port HP and
low pressure LP. Oil is admitted through
the hole in poppet C and because of the HP
differential area between diameters A and
B relief valve poppet D and check valve

LP
poppet K are tightly seated as shown in C
the first step.

E
The oil pressure in the high pressure port
Hp has reached the setting of the pilot
poppet spring force and unseats the pilot HP
poppet E and oil flows around the poppet
through the cross drilled holes and to the

LP
low pressure area LP.

D E
The loss of oil behind poppet C, effected
by the opening of pilot poppet E, causes
poppet C to move back and seat against
HP
pilot poppet E. This shuts off the oil flow
to the area behind relief valve poppet D,
LP

and causes a low pressure area internally.

C

D
The imbalance of pressure on the inside
as compared to that of the high pressure
port HP, forces the relief valve poppet D to HP
open and relieve the oil directly to the low
pressure chamber LP in the valve.
LP

7407AWE52

6-25
(2) As anti void

The anti-void unit supplies oil to the high

K G
pressure port HP when cavitation has
occurred. A lower pressure exists in the A
port HP compared to the low pressure
chamber LP. The difference between the HP
effective area of diameter A and G
causes imbalance of the check valve

LP
poppet K which unseats, thus allowing oil
from the low pressure chamber LP to
enter the port HP and fill the void. 7407AWE53

(3) As separate anti void

The anti-void check valve opens when M O-ring

cavitation occurs in the high pressure port
HP and supplies oil from the reservoir LP
to help fill this void. The poppet M is held
A1
A2

on its seat by the port pressure HP, acting HP

on the larger area behind the O-ring.
When pressure HP drops below LP
atmosphere, the tank pressure LP
Spring
operating on the annular area A1-A2 will
overcome the port pressure HP and the 7407AWE54

spring force to open the poppet. When the

void is eliminated the spring will return the
poppet which will then be tightly seated by
the port pressure HP.

6-26
6) PORT RELIEF VALVE
(1) As relief
A D LP B K
The relief valve is in communication
between the high pressure port HP and
low pressure LP. Oil is admitted through
the hole in poppet C and because of the HP
differential area between diameters A and
B relief valve poppet D and check valve
poppet K are tightly seated as shown in LP C
the first step.

LP E
The oil pressure in the high pressure port
Hp has reached the setting of the pilot
poppet spring force and unseats the pilot HP
poppet E and oil flows around the poppet
through the cross drilled holes and to the
low pressure area LP. LP

The loss of oil behind poppet C, effected D LP E

by the opening of pilot poppet E, causes
poppet C to move back and seat against
pilot poppet E. This shuts off the oil flow to HP
the area behind relief valve poppet D, and
causes a low pressure area internally.
LP C

The imbalance of pressure on the inside LP D

as compared to that of the high pressure
port HP, forces the relief valve poppet D to
open and relieve the oil directly to the low HP
pressure chamber LP in the valve.

LP

7407AWE55

6-27
7. PILOT OIL SUPPLY UNIT
1) STRUCTURE

5
1

P
2
U

T
6

P2 2
7607B6WE46

3MPa
Port Port name Port size
U
P1 From steering pump 3/4-16UNF

4.5MPa P2 Pluging 3/4-16UNF

U Supply to RCV lever 9/16-18UNF
P1 T T To hydraulic tank 9/16-18UNF
HYDRAULIC CIRCUIT 7807AWE49

1 Manifold complete 4 Accumulator

2 Reducing valve 5 Gasket
3 Seal kit 6 Relife valve

2) OPERATION
The pilot supply manifold reduces the pressure from the high pressure circuit to a low pressure
circuit in order to supply the remote control valve.
The accumulator satisfies short term peak power demands and is a source of emergency power in
case of main circuit pressure failures.
The unit consists of the housing, the accumulator(4), the relief valve (6), the check valve and the
reducing valve (2).
The flow path is from the high pressure circuit through port P2 to the pressure reducing valve (2).
The pressure is reduced in the reducing valve (2) and oil passes the check valve into the
accumulator (4) and to the port U, which is connected with the remote control valve.
The pressure relief valve (6) protects the pilot circuit in case of the reducing valve (2) failures or
external increase of pressure.

6-28
8. BOOM AND BUCKET CYLINDER
The boom cylinders are two unit and the bucket cylinder is one unit. They use a bolt on rod guide.
The piston (12) threads on to the rod (2) and is retained by a nut (18).
The piston seals against the tube (1) with piston seal (15). Two wear rings (16) are located on each
side of the piston seal.
The gland(3, the rod guide) seals against the tube with an O-ring (10). The cylinder thread seals
against the rod with a lip type buffer ring (7) and a rod seal (5). A dust wiper (8) cleans the rod when
it is retracted.
1) BOOM CYLINDER

8,9 5,6 19 7 10,11 23 22 3 4 1 2 13,14 17 15 16 12 18

20 21 27 , 28

24 , 25 ,26

7309S6WE46

1 Tube assembly 11 Back up ring 21 Pipe assembly

2 Rod assembly 12 Piston 22 O-ring
3 Gland 13 O-ring 23 Bolt
4 Bushing 14 Back up ring 24 Clamp
5 Rod seal 15 Piston seal 25 Bolt
6 Back up ring 16 Wear ring 26 Spring washer
7 Buffer ring 17 Dust ring 27 Pin bushing
8 Dust wiper 18 Lock nut 28 Dust seal
9 Snap ring 19 Bolt
10 O-ring 20 Pipe assembly

6-29
2) BUCKET CYLINDER

8,9 5,6 19 7 10,11 3 4 1 2 13,14 17 15 16 12 18 23 22

20

26, 25

21

24
7309S6WE47

1 Tube assembly 10 O-ring 19 Bolt

2 Rod assembly 11 Back up ring 20 Pipe assembly
3 Gland 12 Piston 21 Pipe assembly
4 Bushing 13 O-ring 22 O-ring
5 Rod seal 14 Back up ring 23 Bolt
6 Back up ring 15 Piston seal 24 Band assembly
7 Buffer ring 16 Wear ring 25 Pin bushing
8 Dust wiper 17 Dust ring 26 Dust seal
9 Snap ring 18 Lock nut

6-30
9. HYDRAULIC OIL TANK
1) STRUCTURE
· The oil from the hydraulic tank is sent from the pump through main control valve to the cylinders.
In the return circuit, the oil from various parts merges.
· A part of oil is cooled in the oil cooler, passes through the hydraulic filter and returns to the
hydraulic tank (1).
· If the hydraulic return oil filter becomes clogged, return filter bypass valve (6) acts to allow the oil
to return directly to the hydraulic tank (1). This prevents damage to the hydraulic filter (7). The
bypass valve (6) is also actuated when negative pressure is generated in the circuit.

4 1 Hydraulic tank sub assy

8
1-1 Hydraulic tank
1-3 1-2 Cover
1-5
1-3 Bolt
1-4 O-ring
1-4 1-5 Suction cover
11 1-6 Cover
1-3
1-7 O-ring
1-2
1-8 Bolt
1-4 2 Sight gauge
9
3 Suction pipe assy
5
4 Air breather
6 5 Spring
1-1 2 6 Bypass valve
7 7 Element assy
8 Socket bolt
9 Strainer assy
10 Bolt
11 Spring
12 O-ring

12

1-7 3

1-6 10

1-8

73096WE23

6-31
2) RETURN OIL FILTER BYPASS VALVE

(1) When the filter is clogged

Bypass valve (1) is opened and the oil
returns directly to the tank without passing 1
through the filter.

·Bypass valve set pressure : 1.36kgf/cm2

(19.3psi)

From MCV
7607B6WE47

6-32
3) AIR BREATHER
The air breather is equipped with the
capacity to perform three functions
simultaneously-as an air filter, breathing
valve, and as a lubrication opening.
(1) Preventing negative pressure inside the
tank
Air breather
The tank is a pressurized sealed type, so
negative pressure is formed inside the
hydraulic tank when the oil level drops
during operations. When this happens,
the difference in pressure between the
tank and the outside atmospheric
pressure opens the poppet in the
breather, and air from the outside is let
into the tank or prevent negative pressure.
(2) Preventing excessive pressure inside
the tank
When the hydraulic cylinder is being
used, the oil level in the hydraulic system
increases and as temperature rises. If
the hydraulic pressure rises above the set
pressure, breather is actuated to release
the hydraulic pressure inside the tank. 73096WE24

6-33
10. ACCUMULATOR
The accumulator is installed at the pilot oil
supply unit. When the boom is left the
raised position, and the control levers are
operated with the engine stopped the
pressure of the compressed nitrogen gas
inside the accumulator sends pilot pressure
to the control valve to actuate it and allow 1
the boom and bucket to come down under 2
their own weight. 3
Type of gas Nitrogen gas (N2)
Volume of gas 0.75 ℓ (0.2 U.S.gal)
Charging pressure of gas 16 kg/cm2 (228 psi)
Max actuating pressure 128 kg/cm2 (1820 psi)
1 Diaphragm
2 Steel pressure vessel
3 Closure button
7803AWE56

6-34
GROUP 2 OPERATIONAL CHECKS AND TROUBLESHOOTING

1. OPERATIONAL CHECKS
This procedure is designed so the mechanic can make a quick check of the system using a minimum
amount of diagnostic equipment. If you need additional information, read structure and function,
Group 1.
A location will be required which is level and has adequate space to complete the checks.
The engine and all other major components must be at operating temperature for some checks.
Locate system check in the left column and read completely, following the sequence from left to right.
Read each check completely before performing.
At the end of each check, if no problem is found (OK), that check is complete or an additional check is
needed. If problem is indicated (NOT OK), you will be given repair required and group location.
If verification is needed, you will be given next best source of information:

·Chapter 2 : Troubleshooting
·Group 3 : Tests and adjustments

6-35
※Hydraulic oil must be at operating temperature for these checks (refer to page 6-49).
Item Description Service action
Hydraulic system warm-up Hold a hydraulic function over OK
procedure relief to heat oil. (don't keep relief Check completed.
condition over 5 seconds at a time)
Run engine at high idle.
Refer to page 6-49. Periodically cycle all hydraulic
functions to distribute warm oil.
Repeat procedure until oil is at
operating temperature.
FEEL : Hydraulic reservoir must be
uncomfortable to hold your hand
against.
(approximately 40 ~50˚C)
Hydraulic pump With bucket flat on ground, actuate OK
performance check boom raise. Time how long it takes Check completed.
to raise boom to full height.
Heat hydraulic oil to NOT OK
operating temperature. LOOK : Boom must raise to full Go to steering unit high
Run engine at high idle. height in less than 7 seconds. pressure check at page
5-26.
IF OK
Do steering system
leakage check at page
5-23.
IF OK
Do main hydraulic pump
flow test at page 6-50.
Control valve lift check With bucket partially dumped, OK
Run machine at low idle. lower boom to raise front of Check complete.
machine.
NOT OK
Slowly move boom control lever Repair lift checks in loader
( R C V l eve r ) t o b o o m l owe r control valve.
position.
Slowly move bucket control lever
to bucket dump position.
LOOK : Boom must not raise
before moving down.
Bucket must not rollback before
dumping.

6-36
 Item Description Service action
Bucket rollback circuit relief Position bucket at a 45˚ angle OK
valve check against an immovable object. Check complete.
Engage transmission in 3rd speed NOT OK
forward. Replace boom lower
check valve.
LOOK : Bucket angle must not
change.
Bucket dump circuit relief Raise front of machine which OK
valve low pressure check bucket at 45˚ angle. Go to next check.
Backdrag with bucket while NOT OK
observing bucket angle. Do loader system and
circuit relief valve test at
LOOK : Bucket must not rollback
page 6-51.
Pilot control valve float With the bucket partially dumped, OK
check lower boom to raise front of Check complete.
machine.
Run engine at low idle. NOT OK
Push control lever to the float
Do pilot control valve
detent position and release lever.
pressure test in group 3.
LOOK : Front of machine lower to
the ground and valve must remain
in float position when lever is
released.

Boom cylinder and Set the boom and bucket as the OK

bucket cylinder drift figure, then stop the engine. Check complete.
check
S t o p t h e e n g i n e, wa i t fo r 5 NOT OK
Heat hydraulic oil to minutes, then start measuring. Go to next check.
operating temperature.
B Measure the amount the lift and
dump cylinder rods retract during 5
minutes. (loaded bucket)
A
A : Retraction of boom cylinder
rod
B : Retraction of bucket cylinder
rod
Boom cylinder must drift less than
26 mm
Bucket cylinder must drift less than
40 mm

6-37
 Item Description Service action
Boom cylinder leakage Dump bucket until teeth or cutting OK
check edge is per pendicular to the Drift is approximately the
ground. same between first and
Heat hydraulic oil to
second measurement.
operating temperature. Raise boom until cutting edge is
about 1 m (3 ft) above ground.
Repair loader control valve
Stop engine. Measure drift from or circuit relief valve.
tooth or cutting edge to ground for
1 minute. NOT OK
If drift is considerably less
Wait 10 minutes.
on second measurement,
Measure drift from tooth or cutting repair cylinder.
edge to ground for 1 minute.
LOOK : Compare the drift rate
between the first measurement
and the second measurement.
Bucket cylinder leakage Raise bucket about 1 m (3 ft) off OK
check ground with bucket level. Drift is approximately the
same between first and
Heat hydraulic oil to Stop engine. Place a support
second measurement.
operating temperature. under boom.
Measure drift from tooth or cutting Repair loader control valve
edge to ground for 1 minute. or circuit relief valve at
page 6-58.
Wait 10 minutes.
Measure drift from tooth or cutting NOT OK
edge to ground for 1 minute. Drift is considerably less
on second measurement.
LOOK : Compare the drift rates
between the first measurement
Repair cylinder.
and the second measurement.
Check valve of safety Put bucket level and position about OK
valve leakage check 1.2 m (4 ft) above ground. Check complete.
Heat hydraulic oil to Place a piece of tape on cylinder
NOT OK
operating temperature. rod at least 51 mm (2 in) from rod
Check or replace safety
guide.
valve.
Run engine at low idle in safety-
release position.
LOOK : Bucket must not drift up.
Pilot control valve Stop engine. Turn key switch to OK
OFF position. Check completed.
(RCV lever) check
Move control lever to all positions
NOT OK
and then release.
Repair pilot control valve.
LOOK : Lever must return to
neutral when released from all
positions.

6-38
 Item Description Service action
Bucket leveler Position bucket fully dumped just OK
(positioner) check above ground level. Check complete.
Run engine at low idle. Move control lever to bucket NOT OK
leveler detent position and release. Do bucket leveler checks.
LOOK : Bucket must rollback to
the level position and control lever
must return to neutral.
If bucket is in a rolled back position
when key is turned ON, control
lever must be returned to neutral
manually if placed in the bucket
leveler detent position.
After bucket is dumped once,
bucket leveler will work normally.
Boom height kickout Position bucket flat on ground. OK
check Check complete.
Move control lever to boom raise
Run engine at low idle. detent position and release. NOT OK
Do boom height kickout
LOOK : Boom must raise to the
check.
set height and stop.
Control lever must return to
neutral.
Cycle time check Function Operating condition. Maximum cycle time
H e a t hy d r a u l i c o i l t o Boom raise Bucket flat on ground to full height. 5.6 sec
operating temperature.
Boom lower Full height to level ground. 3.0 sec
Run engine at high idle.
Bucket dump Boom at full height. 1.0 sec
Bucket rollback Boom at full height. 1.5 sec
Steering [No. of Frame stop to frame stop. 3.7 turns
turns]
OK
Check complete.
NOT OK
Go to slow hydraulic
functions in group 2.

6-39
※MEASURING BOOM AND BUCKET CYCLE TIME
1) MEASUREMENT CONDITION
·Coolant temperature : Inside operating range
·Steering position : Neutral
·Hydraulic temperature : 40~50˚C
·Bucket : Unloaded
·Engine speed : High idling

2) MEASURING TOOL
· Stop watch (1EA)

3) MEASURING PROCEDURE
(1) LIFTING TIME OF BOOM Lifting time of boom

Set the bucket near the maximum tilt back

position and at the lowest position on the
ground. Raise the bucket and measure
the time taken for bucket to reach the
maximum height of the boom.

73096WE25

(2) LOWERING TIME OF BOOM

Set the bucket horizontal with the boom at Lowering time of boom
the maximum height, lower the bucket and
measure the taken for the bucket to reach
the lowest position on the ground.

73096WE26

(3) DUMPING TIME OF BUCKET

Raise the boom to the maximum height Dumping time of bucket
Rollback time of bucket
and measure the time taken for the bucket
to move from the maximum tilt back
position to the maximum dump position
(4) ROLL BACK TIME OF BUCKET
Raise the boom to the maximum height
and measure the time taken for the bucket
to reach the maximum tilt back position. 73096WE27

6-40
2. TROUBLESHOOTING
※ Diagnose malfunction charts are arranged from most probable and simplest to verify, to least
likely, more difficult to verify. Remember the following steps when troubleshooting a problem :

Step 1. Operational check out procedure (see section 1)

Step 2. Operational checks (see group 2)
Step 3. Troubleshooting
Step 4. Tests and adjustments (see group 3)
Problem Cause Remedy
Noisy hydraulic pump Low oil supply or wrong viscosity. Fill reservoir with recommended oil.
Plugged or pinched suction line. Clean or replace line.
Air in oil. Check for foamy oil. Tighten
connections.
Replace O-rings and or lines.
Plugged suction strainer. Inspect and clean strainer in reservoir.
Loose or missing hydraulic line clamps. Tighten or replace clamps.
Hydraulic lines in contract with frame. Inspect and repair.
Worn or damaged pump. Do hydraulic pump performance check
in group 2. Do hydraulic pump flow test
in group 3.
No or Slow hydraulic Failed or worn hydrualic pump. Do performance check.
functions
Cold oil. Warm oil up.
Slow engine speed. Adjust engine speed.
Check high idle speed.
Suction line air leak. Check for foamy oil.
Low oil supply. Add recommended oil.
Wrong oil viscosity. Use recommended oil.
Oil leaking past cylinders or control Check cylinder drift in group 2.
valve.
Blocked or damaged line. Inspect lines.

Faulty pilot control valve (RCV). Do pilot control valve (RCV) pressure
test in group 3.
Binding loader control valve (MCV) Inspect valve.
spool.
Faulty steering unit. Check steering unit specification.

6-41
 Problem Cause Remedy
No steering or hydraulic Low oil level. Add recommended oil.
function
Failed hydraulic pump. Remove and inspect return filter for
metal pump particles.
No hydraulic functions Failed hydraulic pump. Remove and inspect return filter for
steering normal metal pump particles, or replace the
pump.
Failed line filter. Remove and inspect line filter for RCV.
Faulty safety valve. Safety valve leakage test or ON, OFF
function test.
Stuck open port relief valve. Replace relief valve.
Boom float function Low pilot control pressure. Do pressure reducing valve pressure
does not work test in group 3.
Faulty pilot control valve (RCV). Replace relief valve.
Loader control valve (MCV) spool Do pressure reducing valve pressure
binding in bore. test in group 3.
One hydraulic function Faulty pilot control valve (RCV). Do pilot control valve pressure test.
does not work. Inspect and repair valve.
Stuck open port relief valve. Replace relief valve.
Oil leaking past cylinder packings. Do boom and bucket cylinder leakage
test in group 3.
Blockage in oil lines or valve. Inspect lines for damage.
Disconnect and inspect lines for internal
blockage.
Loader control valve (MCV) spool stuck Inspect and repair valve.
in bore.
Low hydraulic power Leakage within work circuit. Do cylinder drift check in group 2.
Low system relief valve (main relief Do loader system and port relief valve
valve) setting. pressure test in group 3.
Low port relief valve setting. Do loader system and port relief valve
pressure test in group 3.

Leaking system relief valve. Remove and inspect valve.

Worn hydraulic pump. Do hydraulic pump performance check
in group 2.
Faulty pilot control valve (RCV). Do pilot control valve pressure test in
group 3.

6-42
 Problem Cause Remedy
Function drifts down Leaking cylinders. Do cylinder leakage checks in group 3.
Leaking seals in circuit relief valve (port Inspect seals. Replace relief valve.
relief valve) or valve stuck open.
Leaking loader control valve (MCV). Repair or replace valve section.
Boom drifts up Leakage in boom down spool. Remove and inspect boom down spool.
Boom down does not Safety valve not operated. Operate valve.
work (engine off)
Stuck pilot control valve. Inspect.
Faulty line filter. Remove and inspect filter.
Accumulation not operated. Inspect.
MCV spool stuck. Inspect and repair valve.
Oil overheats Low oil viscosity in hot weather. Use recommended oil.
Excessive load. Reduce load.
Holding hydraulic system over relief. Reduce load.
Leakage in work circuit. Do boom and bucket cylinder leakage
test in group 3.
Plugged fins in oil cooler. Inspect and clean oil cooler.
Internally plugged oil cooler. Do hydraulic oil cooler restriction test.
Incorrect system or circuit relief valve Do loader system and circuit relief valve
setting. pressure test in group 3.
Restriction in oil lines or loader control Inspect for dented or kinked lines.
valve (MCV).
Malfunctioning steering valve. Do hydraulic system restriction test in
group 3.
Leaking system main relief valve. Do hydraulic system restriction test in
group 3.
Remove and inspect valve and seals.
Worn hydraulic pump (internal leakage). Do hydraulic pump performance check
in group 2.
Function drops before Stuck open lift check valve. Do control valve lift check in group 2.
raising when valve is
activated
Hydraulic oil foams Low oil level. Add recommended oil.
Wrong oil. Change to recommended oil.
Water in oil. Change oil.
Loose or faulty suction lines (air leak in Tighten or install new lines.
system).
Remote control valve Leaking plunger seals. Remove, inspect and replace plunger
(RCV) leaking seals.

6-43
※ Followings are general precautions for the hydraulic system and equipment.
1) Every structure has its limit of strength and durability. The relief valve is installed to limit the
pressure on the hydraulic equipment and protect various parts of the wheel loader from possible
damage. Therefore, never change the preset pressure of the relief valve unless absolutely
necessary.
2) Since the hydraulic equipment is built with precision, the presence of only the slightest amount of
dust and / or other particles in the hydraulic circuit might cause wear and/or damage, resulting in
unstable functions and/or damage, resulting in unstable functions and/or unexpected accidents.
Therefore, always keep hydraulic oil clean. Periodically, check the filter in the return circuit and
replace the element as necessary.
3) Extract about 200cc of hydraulic oil from the tank as a sample every 6 months. If possible, have it
analyzed by a specialist to confirm that the oil can still be used. Never extract the oil for sampling
until the oil temperature has become the normal operating temperature. Since the replacement
period varies depending on operating conditions, refer to Operator's Manual and change oil.
4) Should the equipment get damaged due to the presence of metal particles and/or foreign matter in
the circuit drain out the hydraulic oil and carry out flushing. Also, replace the filter element and
clean the hydraulic tank. Change the hydraulic oil entirely.
5) When checking the filter, if found metal particles in the element, drain out the hydraulic oil entirely,
flush the whole circuit, and then fill with new oil. The presence of metal particles may indicate
internal damage to the equipment. In such a case, check carefully before flushing, and repair or
replace as required.
6) To add and/or change the hydraulic oil, always use recommended oil. (Refer to the list of
recommended oils and lubricants at page 1-22, Recommended lubricants
lubricants..) Never mix oil of
different makes of kinds.
7) To change the hydraulic oil, use a clean vessel and funnel for pouring it into the tank. Never use
cloth because it might cause the presence of lint in the circuit.
8) When removing the hydraulic equipment, be sure to put plugs or caps on hoses, tube lines and
ports. Also, enter mating marks for later identification.
9) Disassemble and/or assemble the hydraulic equipment only in a clean place free of dust. When
disassembling, be careful about the interchangeability of parts, and clean the disassembled parts
with pure and clean mineral cleansing oil. Clean the internal passages as well. After the parts
have dried, wipe them off with a clean lint-free cloth.
10) When overhauling the hydraulic equipment replace all O-rings, backup rings, etc. with new ones.
Assemble O-rings with grease or vaseline applied.
11) After installing the equipment, add more hydraulic oil to make up for that lost during disassembly.
12) Tighten joints correctly. Loose joints will cause the hydraulic oil to leak. If the oil leaks, the tank oil
level drops and air gets sucked in, so the pump will break down. Also loose joints in suction lines
will take air in and might cause abnormal noise, malfunction or damage to pumps.

6-44
GROUP 3 TESTS AND ADJUSTMENTS

1. HYDRAULIC OIL CLEAN UP PROCEDURE USING PORTABLE FILTER CADDY

※ Service equipment and tool
·Portable filter caddy
·Two 4000 mm × 1in 100R1 Hoses
·Quick disconnect fittings.
·Discharge wand
·Various size fittings.
※ Brake system uses oil from hydraulic oil
tank. Flush all lines in the brake, pilot,
steering system and cut off system.
Disassemble and clean major
components for brake and steering
system. Remove and clean pilot caps
from main control valve.
Brake and steering components may fail
if brake and steering system is not
cleaned after hydraulic oil tank
contamination.
1) If hydraulic system is contaminated due to
a major component failure, remove and
disassemble steering cylinders to clean
debris from cylinders.
2) Install a new return filter element. Inspect
filter housing before installing new element.
※ For a failure that creates a lot of debris,
remove access cover from hydraulic oil
tank. Drain and clean hydraulic oil tank of
fill the specified oil to hydraulic oil tank
through upper cover.
3) To minimize oil loss, pull a vacuum in
hydraulic oil tank using a vacuum pump.
Connect filter caddy suction line to drain
port at bottom of hydraulic oil tank using
connector. Check to be sure debris has not
closed drain port.
4) Put filter caddy discharge line into hydraulic
oil tank filler hole so end is as far away from
drain port as possible to obtain a thorough
cleaning of oil.

6-45
5) Start the filter caddy. Check to be sure oil is
flowing through the filters.
Operate filter caddy approximately 10
minutes so oil in hydraulic oil tank is
circulated through filter a minimum of four
times.
※ Hydraulic oil tank capacity : 92 ℓ(24.3
U.S. gal)
Leave filter caddy operation for the next
steps.
6) Start the engine and run it at high idle.
※ For the most effective results, cleaning
procedure must start with the smallest
capacity circuit then proceed to the next
largest capacity circuit.
7) Operate all functions, one at a time,
through a complete cycle in the following
order: Clam, steering, bucket, and boom.
Also include all auxiliary hydraulic functions.
Repeat procedure until the total system
capacity has circulated through filter caddy
seven times, approximately 30 minutes.
Each function must go through a minimum
of three complete cycles for a through
cleaning for oil.
※ Filtering time for machines with auxiliary
hydraulic functions must be increased
because system capacity is larger.
8) Stop the engine. Remove the filter caddy.
9) Install a new return filter element.
10) Check oil level in reservoir; Add oil if
necessary.

6-46
2. BOOM HEIGHT KICKOUT ADJUSTMENT
1) Lift the boom up to a desired height, set the
boom control lever at hold, then stop the
engine.
Be careful lest work equipment fall down.
Put the hydraulic safety lock lever in the Boom
LOCK position.

Proximate switch
7707WE20

2) Loosen nuts and bolts then tighten them

after adjusting the plate or proximate switch Bolt
so that it comes in contact with the center Nut
of the probe of the proximate switch.
Boom

Plate
7707WE21

3) Loosen the nuts so that a clearance

between the plate and the probe of the
proximate switch are maximum 6 mm. Max 6mm

Boom

7707WE22

4) Start the engine. Position the bucket on the

Detent position
ground. Then lift the bucket to a desired
height by using the control lever and
Neutral
release the hand.
P

Confirm the lever automatically returns to

the neutral position and the boom (the
bucket) stop at the adjusted position.

7409S4OP30

6-47
3. TEST TOOLS
1) CLAMP-ON ELECTRONIC TACHOMETER
INSTALLATION
·Service equipment and tools
B
Tachometer
A : Clamp on tachometer.
Remove paint using emery cloth and
C
connect to a straight section of injection
line within 100 mm (4 in) of pump. Finger
Tighten only-do not over tighten. D
B : Black clip ( - ). Connect to main frame.
C : Red clip (+). Connect to transducer. A
D : Tachometer readout. Install cable.
75795SE32

2) DIGITAL THERMOMETER INSTALLATION

·Service equipment and tools
Digital thermometer
A : Temperature probe.
Fasten to a bare metal line using a tie A
band. Wrap with shop towel. C
B : Cable. B
C : Digital thermometer.

75795SE33

3) DISPLAY MONITOR TACHOMETER

The display monitor tachometer is accurate
enough for test work.

75795SE35

6-48
4. HYDRAULIC OIL WARM UP PROCEDURE
1) Install temperature reader (see temperature
reader installation procedure in this group).

2) Run engine at high idle.

3) Hold a hydraulic function over relief to heat
the oil.

4) Periodically cycle all hydraulic functions to

distribute warm oil.

5) Heat oil to test specification (approx. 45˚C).

※ Ride control system (option)

Ride control valve
Attention
1) Before carrying out any maintenance work
the accumulators must be unloaded (zero
pressure).
2) For this, unscrew the plug (A) then rotate the
drain screw (B), located under the plug (A), 2
turns anti-clockwise with 3 mm L-wrench.
B
3) The lifting system must firstly be secured A
against lowering. 73096WE28

4) After carrying out maintenance work, screw

the plug (A) and drain screw (B).
·Tightening torque
A : 0.71 kgf·m (5.16 lbf·ft)
B : 0.36 kgf·m (2.58 lbf·ft)

6-49
5. MAIN HYDRAULIC PUMP FLOW TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed 2100±25 rpm
Test pressure 210±5 bar (2990 psi)
Flow meter
Maximum pump flow 138ℓ/min (36.5 gpm)
· FLOW METER GAUGE AND TOOL
To MCV
Gauge 0~35 MPa (0~350 bar, 0~5000 psi)
Temperature reader
1) Make test connections. P
EF

2) Install temperature reader.

(see temperature reader installation Priority valve
procedure in this group)
3) Heat hydraulic oil to specifications.
(see hydraulic oil warm up procedure in this
group)
Hyd tank
4) Run engine at test specifications.
5) Close flow meter loading valve to increase
pressure to test specifications.
6) Read flow meter.
7) If flow is below specifications, check suction
line and suction pressure for abnormality
before removing pump. 7309S6WE31

6-50
6. LOADER
L ADER SYSTEM AND PORT RELIEF
VALVE PRESSURE TEST
· SPECIFICATION
Oil temperature (40~50˚C)
D U R
Relief valve Engine speed Relief pressure
210±10 kg/cm2
System (M) High
(2990±140 psi)
Boom 240±10 kg/cm2
Low
raise (U) (3410±140 psi)
M
Bucket 240±10 kg/cm2
Low
rollback (R) (3410±140 psi)
Bucket 240±10 kg/cm2 Main control valve
Low
dump (D) (3410±140 psi)

· Gauge and tool

Gauge 0~35 MPa (0~350 bar, 0~5000 psi)
M : System (main) relief valve
R : Bucket rollback relief
D : Bucket dump relief
To MCV
U : Boom raise relief
1) Install fitting and pressure gauge to test
port in pump delivery line.
2) Install temperature reader.
(see temperature reader installation
procedure in this group)
3) Heat hydraulic oil to specifications.
(see hydraulic oil warm up procedure in this
group)
Hyd tank
4) To check the system relief (M), run engine
at high idle. Lower boom to bottomed
position.
Slowly activate boom down function while
watching pressure gauge. If pressure is not
to specification, loosen lock nut on system
relief valve (M) and adjust to specification. 7309S6WE23

6-51
※ Do not adjust the system relief valve
above 210 kg/cm2 (2990 psi). Damage to
the pump will result from excessive
pressure settings.

6-52
7. HYDRAULIC SYSTEM RESTRICTION
TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed High idle
Maximum pressure 2 MPa (20 bar, 285 psi)
at steering unit.
Maximum pressure 1 MPa (10 bar, 145 psi)
at main control valve
· GAUGE AND TOOL
Gauge 0~7 MPa (0~70 bar, 0~1000 psi) 2EA
This test will check for restrictions in the
hydraulic system which can cause
overheating of hydraulic oil.
T

1) Install temperature reader.

(see temperature reader installation
procedure in this group) Steering unit

2) Heat hydraulic oil to specifications.

(see hydraulic oil warm up procedure in this
group)
3) Connect fitting and gauge to steering unit.
4) Connect fitting and gauge to main control
valve.
Do not operate steering or loader funct-
ions or test gauge may be damaged.
5) Run engine at specification and read
pressure gauges.
If pressure is more than specification at the Main control valve
loader control valve, check for a kinked,
dented or obstructed hydraulic line. Check
loader control valve for a binding spool.
If pressure is more than specification at the
steering unit, inspect neutral condition of
the steering unit and priority valve for a
stuck spool. Make sure orifice plugs are
installed in ends of priority valve spool.
Check for plugged orifice in priority valve
LS port and dynamic signal orifice on the
spool of priority valve. 7407B6WE24

6-53
8. LOADER CYLINDER DRIFT TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F) B
Boom horizontal
Bucket horizontal
Bucket loaded
Item Standard value A

Retraction of boom
26 mm
cylinder rod A : Retraction of bucket cylinder rod
Retraction of bucket B : Retraction of boom cylinder rod
40 mm
cylinder rod
· GAUGE AND TOOL
Stop watch
Temperature reader
Put the hydraulic safety lock lever in the
lock position.
Do not go under the work equipment.
1) Set the boom and bucket horizontal, then
stop the engine.
2) Stop the engine, wait for 5 minutes, then
start measuring.
3) Measure the amount the boom and bucket
cylinder rods retract during 15 minutes. 7409S6SE61

6-54
9. BOOM AND BUCKET CYLINDER LEAKAGE TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed Low idle
Maximum leakage 15 mℓ/min (1/2 oz/min)
· GAUGE AND TOOL
Temperature reader
Stop watch
Measuring container
1) Fasten temperature sensor to head end
port of cylinder to be tested. Cover sensor
with a shop towel.
2) Heat hydraulic oil to specifications (see
hydraulic oil warm up procedure in this
group).
Never work under raised equipment
unless it is supported with a hoist or
support stands.
3) Full extend the cylinder to be tested. If
testing the boom cylinders, restrain boom in
the fully raised position using a hoist or a
stand.
※ Check cylinders for leakage in the fully
extended position only. In the retracted
position contacts the end of the cylinder
and seals off piston seal leakage.
4) Remove and plug cylinder rod end hose or
line.
5) Run engine at slow idle. Activate control
lever to extend cylinder for 1 minute over
relief while measuring leakage for open
port.
If leakage is within specification, excessive
cylinder drift is caused by leakage in the
(770-3ATM) 6-56
loader control valve or circuit relief valve.

6-55
10. PILOT CONTROL VALVE P
PRESSURE
RESSURE TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed Low idle
Begin metering 1/4" of lever travel
Pressure in detent :
Boom float detent 1.9 MPa (19 bar)
Pressure at detent position :
Boom power down 13~17bar
Boom raise 13~17bar
Bucket rollback 13~17bar
Bucket dump 13~17bar
· GAUGE AND TOOL
Gauge 0~7 MPa (0~70 bar, 0~1000 psi)
As the control lever is moved from neutral,
the pilot pressure will suddenly jump up to
approximately 5.8bar at 1/4in. travel. The
pressure should then increase smoothly to
the specification at the FEEL position (or
3/4 lever travel), and then jump up about
430psi as the lever is moved into detent.
This test will determine if adequate pilot
pressure is available to move the loader
control valve spools.
※ The FEEL position is when lever is
moved to feel the ramp of the detent
before lever passes into detent position.
1) Lower boom to ground.
2) Connect gauge to the pilot pressure port of
function to be checked.
3) Install temperature reader (see temperature
reader installation procedure in this group).
4) Heat hydraulic oil to specification (see
hydraulic oil warm up procedure in this
7607B6WE41
group).

6-56
11. PILOT OIL SUPPLY UNIT P
PRESSURE
RESSURE TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed Low idle and stop
Pilot pressure setting
30~35 bar (430~500 psi)
Relief valve setting pressure 45 bar
Accumulator precharging pressure 16 bar
· GAUGE AND TOOL
Gauge 0~7 MPa (0~70 bar, 0~1000 psi)
The pilot supply unit consist of the pressure
reducing valve, the relief valve and an
accumulator. This regulates pressure to the
pilot control circuit.
1) Connect gauge to test port on the screw
coupling.
2) I n s t a l l t e m p e r a t u r e r e a d e r ( S e e
temperature reader instakkation procedure
in this group).
3) Heat hydraulic oil to specification (see
U
hydraulic oil warm up procedure in this T P2

group).
4) Run engine at loe idle for 1 minute and stop
engine, wait for 5 minutes, Then start
measuring.
5) If pressure in not within specifiactions,
replace valve.

7707WE26

6-57
12. CYCLE TIME TEST
· SPECIFICATION
Oil temperature 45±5˚C (113±9˚F)
Engine speed High idle
Function Operating conditions Maximum cycle time (seconds)
Boom raise Bucket flat on ground to full height 5.6
Boom lower (float) Full height to ground level 3.0
Bucket dump Boom at full height 1.0
Bucket rollback Boom at full height 1.5
Steering (number of turns) Frame stop to stop 3.7 turns

Hydraulic pump performance cycle time.

Function Operating conditions Maximum cycle time (seconds)
Bucket flat on ground to full height
Boom raise 8.0
while holding steering over relief

6-58
13. HYDRAULIC OIL FILTER INSPECTION
PROCEDURE
1) Lower the bucket to the ground, stop the
engine, move the control lever back and
forth several times, and clean all over the
upper surface of the hydraulic oil tank.
2) Remove the bolts and take out the filter
case cover and O-ring.
3) Remove the spring and bypass valve.
4) Remove the filter element from the tank. Cover
O-ring
5) Check the element and the filter case Spring
bottom for debris. Excessive amounts of By-pass valve
brass and steel particles can indicate a
Return filter
failed hydraulic pump or a pump failure in
process. A rubber type of material can
indicated cylinder packing or other packing
failure.
※ The hydraulic oil filter in the filter case of
the hydraulic oil tank should be replaced
every 250 operating hours or more often.
When the filter element is replaced,
please keep as follows.
(1) Clean the inside of the filter case.
(2) Place new element in the proper positions
inside the filter case.
(3) Install the bypass valve and spring.
Make sure the element stand upright, and
check for complete contact of the element
bottom with the filter case bottom.
(4) Install the O-ring and filter case covers.
Tighten them with bolt. Replace the
O-ring with new one if damaged.sa 73096MI24

6-59
GROUP 4 DISASSEMBLY AND ASSEMBLY

1. MAIN PUMP
1) STRUCTURE

9
6

9
13
11
12
14

2 16
15
14

13 17
11
12
1 5

13
11
12
14
9
7
10
9
8

4
14

13
11
12
7309S6WE48

1 Front cover 7 Driven gear set 13 Square seal

2 Housing 8 Connector shaft 14 Dowel pin
3 Carrier 9 Thrust plate 15 Washer
4 Housing 10 Lip seal 16 Stud bolt
5 Rear cover 11 Rubber seal 17 Hex nut
6 Drive gear set 12 Back up seal

6-60
2) MANDATORY REPLACEMENT PARTS
Discard all seals including square seals, lip seals, rubber seals and back up seals. Fit new seals on
reassembly. Thrust plates should also be replaced with new items from seal kit.
3) HANDLING/STORAGE
HANDLING/STORAGE
While disassembling pump, ensure no surfaces are scored or marked in any way. A rubber
surfaced table will be beneficial. All components must be placed in a clean, dry and safe area.
Leakage will be created by scratches on components. If parts are to be left for any period ensure
they are not exposed to dirt, dust and corrosion. Keep gears separate from each other in protective
boxes.
4) INSPECTION
INSPECTION OF PARTS
Wash all parts in a solvent and dry.
(1) Cover, housing and carrier
The pump must be replaced if the damage listed is present.
Feature Damage
Corrosion, nicks or burrs (slight burrs can be removed using and india
Surfaces
stone)
Machined sealing lnterfaces Scores, cracks or corrosion

(2) Gears
The pump must be replaced if the damage listed is present.
Feature Damage
Corrosion, nicks or burrs (slight burrs can be removed using an lndia
Surfaces stone).
Wear due to seal (s)
Journals Pitting, wear, sufficient wear to change outside diameter
Tooth Cracks or heavy scoring or chipped
Splines/keyways Distortion of wear
End faces Wear, cracks

(3) Bolts/studs
The pump should be replaced if the damage listed is present.
Feature Damage
Corrosion, nicks or burrs(slight burrs can be removed using an lndia
Surfaces
stone), cracks or scoring, distortion or damage to thread form

6-61
5) ASSEMBLY
(1) Prepare sub assembled parts (front and
rear cover, carrier, housing, thrust plate).
※ Grease must be spreaded slightly on each
seal.

7407B6MP01

(2) Put section sub assembly on the

assembly table.
Assemble dowel pins.

7407B6MP02

(3) Assembly gear housing and thrust plate.

※ Check the contact status of square seal.
Arrow
mark

Inlet

Push a thrust plate down on front cover. 7407B6MP03

(4) Mount a jig on the shaft end to protect lip

seal.
Assemble drive gear.

7407B6MP04

6-62
(5) Assemble driven gear.
Spread hydraulic fluid around gear set.

7407B6MP05

(6) Assemble thrust plate. Seal is on the left side of gears.

Rotate the shaft gear and check status of
gear set.
Assemble dowel pins and connector shaft.

7407B6MP06

(7) Assemble sub assy of carrier.

Inlet hole is located on the right side.
※ Outlet drill hole is located at the bottom of
carrier. Sub assy of piggy back type carrier
is the same.

7407B6MP07

(8) Assemble gear housing and thrust plate.

※ Check the contact status of square seal. Inlet

7407B6MP08

6-63
(9) Assemble drive gear set.
Spread hydraulic fluid around gear set.

7407B6MP09

(10) Assemble thrust plate.

Rotate the shaft gear and check status of
gear set.
Assemble dowel pins and connector
shaft.

7407B6MP10

(11) Assemble the rear cover.

Check the contact status of square seal.
Outlet

7407B6MP11

(12) Assemble stud bolt and washer.

※ Washer : smooth - convex side up
※ Keep bolts in dry condition after washing.

7407B6MP12

6-64
(13) Nuts are pre-assemble by hand.

7407B6MP13

(14) Use air impact to assemble nuts.

At this time, assemble nuts diagonally.

7407B6MP14

(15) Use torque wrench to assemble.

·Tightening torque : 15 kgf·m
(108 lbf·ft)

7407B6MP15

6-65
2. MAIN CONTROL VAVLE
1) STRUCTURE

20

19 1
39
11 6 40
21-1
4 6-1 38
23 3 34 36
25 35
30
24
21
8
16
5 8
33
18 8 11
1 37 9 29
32
22
21-1 13
8 31
26
2-1 28 13
2 14
40 21 4
12 19
27
12 15
14
4

19

10 20

7407B6WE45

1 Nut 14 Screw 28 Spool

2 Plug 15 Screw 29 Spool
2-1 O-ring 16 Anti void assy 30 Spring
3 O-ring 18 Spool cap 31 Spring
4 O-ring 19 Spool cap 32 Back up ring
5 Cap screw 20 Cap screw 33 Inlet section assy
6 Plug 21 Spool retainer 34 Spool section assy
6-1 O-ring 21-1 Back up ring 35 Spool section assy
8 O-ring 22 Spool retainer 36 Outlet section assy
9 Spring 23 Screw 37 Poppet
10 Main relief valve 24 Washer 38 Tie rod
11 Port relief valve 25 Spacer 39 Tie rod
12 Spring seat 26 Spring 40 Nut
13 Washer 27 Spring

6-66
2) ASSEMBLY AND DISASSEMBLY
(1) Lay out valve components on a clean, flat
working surface. The inlet assembly will
include an O-ring, and the spool section
(s) include an O-ring, a load check poppet
and a load check spring. Tools required
for basic valve assembly include 3/4 and
11/16 open or box end wrenches and a
torque wrench with thin wall sockets.
7406S MCV05(1)

(2) Assemble tie rod nuts to one end of each

tie rod with one or two threads showing.
Insert tie rods through tie rod holes of inlet
(large tie rod at top). Lay inlet on end with
tie rods up, place O-ring into position.

7406S MCV05(2)

(3) Place first spool section (O-ring side up)

on inlet section, position O-ring and insert
load check poppet (nose down) and
spring (behind poppet) into load check
cavity as shown. Repeat this procedure
for each spool section ; The load check
springs are compressed by the following
sections during assembly.

7406S MCV05(3)

(4) Position end section on last spool section

as shown and hand tighten tie rod nuts.
The end section on picture is a "turn
around" section without ports. Universal
outlet/power beyond section and power
beyond and closed center sections are
also used as end sections. These end
sections do not have O-ring grooves.

7406S MCV05(4)

6-67
(5) Position valve assembly with the mounting
pads of the end sections on a flat surface.
To obtain proper alignment of end
sections relative to the spool sections
apply downward pressure to the end
sections ; Snug tie rod nuts to about 10
lbf·ft.
Final torque the two 11/16 nuts to 48±5
lbf·ft ; Final torque the 3/4 nut to 74±8
7406S MCV06(1)
lbf·ft. Check for proper spool movement.

(6) Install auxilliary valves and plugs and

torque to proper specifications.
General assembly notes :
A. Lever assemblies can be installed on
section before or after complete valve
assembly.
B. The load check and spring may be
omitter from assembly in certain circuit
conditions (i.e., motor spools).
7406S MCV06(2)

6-68
3. REMOTE CONTROL VALVE
1) STRUCTURE

36

13
45 38 15
37 14
16
33 8
5
34
9
7
,
41,42,43,44 35 6

4
32
12
27
26 28 11
1,3,4 1 10
4
25 3 2
3
2
29 T

24 30 4 1
31 3 2

2 1
1,3,4

23
46
4 1

22 49 49
3 2

20 47 47
19 19
21 48
18 48
1,3,4
2
39,40,41,42

17
7407S6WE48

1 Body 14 Rod seal 27 Nut 40 Rear holder

2 O-ring 15 O-ring 28 Plug 41 Terminal
3 Plug 16 Push rod 29 Nut 42 Seal wire
4 Spring 17 Plate 30 Set screw 43 Housing
5 Spring seat 18 Rod stopper 31 Nut 44 Rear holder
6 Spool 19 Bushing 32 Nut 45 Clip band
7 Spring seat 20 Rod 33 Handle bar 46 Plug
8 Stopper 21 Magnet 34 Nut 47 Connector
9 Spring 22 Plate 35 Boot 48 O-ring
10 Spring seat 23 Joint assy 36 Handle assy 49 O-ring
11 Spring 24 Joint assy 37 Nut
12 Spring seat 25 Plate 38 Spring washer
13 Plug 26 Washer 39 Housing
6-69
2) DISASSEMBLY
(1) Remove the boot (35) and loosen nut
(34).
· Tool : spanner 19 mm

7607BRCV01

7607BRCV02

(2) Remove nut (32).

7607BRCV03

6-70
(3) Disassemble plate kit.

7607BRCV04

(4) Remove rod (20).

7607BRCV05

(5) Remove joint assembly (23).

· Tool : spanner 17 mm

7607BRCV06

(6) Disassemble plate (22).

7607BRCV07

6-71
(7) Disassemble magnet (21) and rod stopper
(18).

7607BRCV08

(8) Disassemble plate (17).

7607BRCV09

(9) Disassemble plug kit.

7607BRCV10

(10) Disassemble spring (4) and spool kit.

7607BRCV11

6-72
(11) Disassemble plug (2).
· Tool : wrench 10 mm

7607BRCV12

6-73
3) ASSEMBLY
(1) Coat oil on O-ring and mount plug (3) into
body assembly (1).

7607BRCV13

(2) Tighten the plug (3).

· Tool : wrench 10 mm
· Tightening torque (M14) :
30±3 kgf·m (217±21.7 lbf·ft)

7607BRCV14

(3) Assemble spring (4).

7607BRCV15

(4) Assemble spool kit.

7607BRCV16

6-74
(5) Assemble plug kit.

7607BRCV17

(6) Assemble plate (17).

7607BRCV09

(7) Assemble magnet (21) at port 1, 3 and 4.

Assemble rod stopper (18) at port 2.

Important

7607BRCV19

(8) Confirm port 2 on the bottom of the body.

7607BRCV20

6-75
(9) Assemble plate (22).

7607BRCV21

(10) Assemble joint assembly (23) and put

grease on joint pin lightly.
· Tools : spanner 17 mm
· Tightening torque (M16) :
45±4.5 kgf·m (325±32.5 lbf·ft)

7607BRCV22

7607BRCV23

(11) Assemble rod (20).

7607BRCV24

6-76
(12) Assemble plate kit.
Put a bit of grease on rod (20) and Joint
(24).

7607BRCV04

(13) Assemble nut (32).

· Tool : spanner 17 mm
· Tightening torque (M12) :
40±4 kgf·m (289±28.9 lbf·ft)

7607BRCV03

7607BRCV02

6-77
(14) Assemble nut (34).
· Tool : spanner 19 mm
· Tightening torque (M12) :
40±4 kgf·m (28±28.9 lbf·ft)

7607BRCV01

(15) Assemble the boot (35).

7607BRCV25

6-78
 SECTION 7 ELECTRICAL SYSTEM

Group 1 Component Location ----------------------------------------------------------------------------------------- 7-1

Group 2 Electrical Circuit -------------------------------------------------------------------------------------------------- 7-3
Group 3 Monitoring System --------------------------------------------------------------------------------------------- 7-21
Group 4 Electrical Component Specification ------------------------------------------------------------------ 7-48
Group 5 Connectors --------------------------------------------------------------------------------------------------------- 7-55
Group 6 Troubleshooting -------------------------------------------------------------------------------------------------- 7-75
 SECTION 7 ELECTRICAL SYSTEM
GROUP 1 COMPONENT LOCATION

1. LOCATION 1

Cab ceiling LH side

A
3 M
2 23
1 M

24 15
5
4 16

14 17
18
21
6 7 8 9 10 11 12 13
22

P
19 20

7309S7EL02

1 Beacon switch (opt) 9 Kick down switch 17 Parking brake switch

2 Rear wiper / washer switch 10 T/M shift mode switch 18 Ride control switch (opt)
3 Mirror defrost switch 11 Clutch cut off mode switch 19 Starting switch
4 Emergency test switch (opt) 12 Multi function switch 20 Engine mode switch
5 Fan control switch 13 Horn switch 21 Machine control unit (MCU)
6 Main light switch 14 Monitor 22 T/M control unit (TCU)
7 Work lamp switch 15 Radio & USB player 23 Engine control unit (ECU)
8 Hazard switch 16 Aircon & heater switch 24 USB socket

7-1
2. LOCATION 2

3 3 2 4

10 11

12

5 6 7 8

7409S7EL02-1

1 Head lamp 5 Start relay 9 Master switch

2 Horn 6 Fuel sender 10 Camera (opt)
3 Proximity switch 7 Battery 11 Work lamp
4 Work lamp 8 Rear combi lamp 12 Number plate lamp

7-2
 CAB ROOF HARNESS

PTC
AC HARNESS

1
2
3

WITH PTC

REAR
OPTION

RELAY
CN-244A

STEER
WIPER

HI
AC

LOW
HEAT

LAMP
TIMER

LAMP
REAR

HORN
WORK

RELAY

WORK

RELAY
WIPER
RELAY
WIPER
UNIT

RELAY
RELAY
FRONT

RELAY

EMERGENCY
MIRROR
A
B
C

FLASHER
SW2

2
2
2
2
2
2

1
1
1
1
1
1
GND 1

86

85
Pf
B
E

BEACON LAMP

NC
NC
NC
NC
MIRROR HEAT SWITCH
MIRROR HEAT

WORK LAMP FRONT

EMERGENCY TEST SW
NC

BOOM POSITION SELECT

NC

NC
NC
REVERCE SW_ON

SWITCH ATT. UNLOCK

BUCKET POSITION SLCT
SWITCH ATT. COM

WORK LAMP REAR

WORK LAMP REAR

3
3
3
3
3
3
SWITCH ATT. LOCK
REVERCE SW_RETURN

5
5
5
5
5
5
WIPER SWITCH

WIPER SWITCH
WIPER SWITCH
WIPER SWITCH
REVERCE SW_AUTO
BLOWER RELAY
REVERSE FAN SIGNAL

WORK LAMP FRONT

CASSETTE_IG
AC CONTROLLER B+

CASSETTE_ILLUMINATION
PTC POWER

CASSETTE/ROOM LAMP
AC 24V

AC OPERATE SIGNAL
ILLUMINATION

30
AC COMP
AC SYSTEM GND

G
IG
A

Hi 4
2
3

Lo 5

4
4
4
4
4
4
4
3

OUT

87 87a
1

3
2

4
4
4

2
2
2
2
2
2
6

1
1
1
1
1
1

3
3
3
3
3
3
5

14
7
13
5

10
10
1

87a
4
3
2
1

5
5
5
5
5
5
15
13
14
15
2

4
4
4
4
4
4
9
5
3
6
8
3

12
11
12
11

B 85

86
8
1
6
9
7
1

85

30
L 87

87
E 86
2
2
A
1

B
7
4
6

C
2
5
8
3

CN-244

CN-102

CR-55
CN-7

CR-11

CR-26
CR-2
CR-3

CR-4
CR-7

CR-37
CN-11

CN-245

CN-9

CR-56

L
L
L
L
L
L

B
Y
Y
Y
B
B
V
Y
B
Y
B
B
V
B
V
B
Y
V
B

R
R
R

G
G
G

W
W
W
W
W
W
W

Br
Br
Br
Br

Gr
Gr
Gr
Gr
Or
Gr

5L
5B

WITHOUT PTC

BW
VW
BW

RW
RW
RW
RW
YOr

BrW
·ELECTRICAL CIRCUIT (1/2)

300
314
315
310
307
306
311
YW 214
211
462
467
460
230
245
242
140
144
141
GW 130
134
131
GW 500
RW 501
251
250
254
460
WOr 120
254
251
333
RW 332
OrW 335
141
GOr 771
RW 770
520
LW 590
YOr 160
332
333
790
791
114
233
234
235
160
237

G02

G02
G01
G01
G08
G09

310B
310A
ROr 210A
230A
300A
300B

440D
WOr 690C

G01F

G01E

G01C
G01D
G01G
240 2.0
G11 2.0

131 1.25
141 1.25
131 1.25
230 0.85

2.0
2.0

2.0

2.0

2.0
0.85

314
315
307
310
311
211
462
245
242
144
134
W 307

440A
1 WIPER MOTOR-LOW
R 315
GROUP 2 ELECTRICAL CIRCUIT

2 WIPER MOTOR-HI
G 311
43 WIPER RY_LOW
Y 310
4 WIPER SW_LOW

520
590
160
Br 314
42 WIPER SW_HI
Y 629
9 RS232 RX 2-MONITOR
L 623
10 RS232 TX 2-MONITOR
GBr 624
37 PROGRAM DUMP-MONITOR
Y 625
CR-59 38 RS232 RX-CLUSTER
Br 422 L 626
86 30 87a 39 RS232 TX-CLUSTER
B G01 RY 627
85 50 PROGRAM DUMP-CLUSTER

RIDE-
87

RELAY
SPEED
OrW 216
86
85 87 87a

CONTROL
Br 217 L 251A
30 13 MIRROR HEATED
Gr 650
14 CLUSTER_BATT. 24V
Or 570C
CR-60 18 SHIFT LEVER_IG
V 580
86 30 87a 27 CLUSTER_ IG
L 425 RW 935
85 6 LAMP-JOYSTICK STR

RIDE-
Br 217 GOr 930
87 TCU_ED6-NEU.

RELAY
15
W 426 LW 920
86 16 TCU_ED5-REV.
85 87 87a

CONTROL
LOr 421 BrW 910
30 17 TCU_ED4-FWD.
WOr 451A
21 SHIFT LEVER_KD
425 ROr 915
CR-58 22 TCU_ED1
426 GrW 925
2 3 4 23 TCU_ED2
G 193 193 VOr 905
1 24 TCU_ED3
BrW 191 540
5

RELAY
Or 190
2

BACK-UP
1 5 4 190A OrW 150 1.25
3
Or MAIN SWITCH_ILL
33
G 180 2.0
34 MAIN SWITCH_HEAD
TO SHEET 2 OF 2

CR-63 LOr 154

35 MAIN SWITCH_ILL
191 YW 214
2 3 4 19 HORN RY
B G01B YOr 184 1.25
1 31 MULTI_HEAD LAMP_LOW
LOr 200 200 R 187 1.25

RELAY
5 32 MULTI_HEAD LAMP_HI
GW 202 202
2
1 5 4 Or 190B
3

STOP LAMP
CR-25
RW 501
86 30 87a 30 FLASHER_L
B G01A B 795
85 12 GROUND_SHIELD
Y 620 L 790
87 7 CAN2 LOW

RELAY
RW 531 Y 791
86 8 CAN2 HI
85 87 87a R 530B LOr 303
30 40 MCU_INT
Gr 305 305

ECM POWER
41 MCU & WASHER
Gr 305A
CR-35
Br 300C
86 30 87a 45 FUSE BOX
B G01 Y 134
85 46 WORK LAMP SWITCH
Gr 550 2.0 VW 144
87 47 WORK LAMP SWITCH

RELAY
RW 531 531 Or 505

POWER
86 28 RH TURN
85 87 87a R 530 2.0 530A GOr 506
30 29 LH TURN
534 BrW 740
57 5V_POWER
WOr 690
CR-38 58 GND_SENSOR
LOr 754
2 3 4 59 TM MODE
R 540 BW 755
CAN2 BUS

1 60 CLUTCH_MODE

335
305
LW 538A

G02A
G02B
5
Or 570 G16

RELAY
2 1
1 5 4 Or 570 RY 627

1
1
4

2
2

NEUTRAL
3
L 626

CN-22
3

PUMP

M
M

CN-103
538 Y 625
CN-127C

CR-5 2

WASHER
86 30 87a
VW 539 539 G16
85 1
G 535 GBr 624
87 4

RELAY
LW 538 L

SAFETY
86
623 3
85 87 87a GOr 534 Y
30
629 CN-126
2
CN-127B

G16
D BATTERY(-)
BW 560
CR-46 J BATTERY(+)
G 993E
86 30 87a E CAN_Hi
L 380 V 994E
85 F CAN_Lo

FUEL
2LW 381 Y 791
87 G CAN2_Hi

RELAY
SERVICE TOLL

Y 370A L 790
86 H CAN2_Lo

WARMER
85 87 87a 2Y 370
30
G16 1
R 781 786
2 B MCU_RS232_RX
Br 782 787
CR-36 3 C MCU_RS232_TX
CONNECTOR_MCU & CAN

W 780 785
2 3 4 4 A MCU_RS232 P_DUMP
CAN BUS

GOr 371 371

1
Y 370B

RELAY
5
RW 372 372
2
1 5 4
CN-127

PRE-HEAT
Y 373 373
3
CN-127A

CN-58A
G16B
A13 GND(MAIN)
CN-36 G16A
A14 GND(MAIN)
MCU

10A BEACON WOr 120 Or 660

15 B38 ELEC. STEER MAIN PUMP PS
20A WORK LAMP_FRONT GW 130 2.0 V 661
16 B27 ELEC. STEER PUMP PS
20A MIRROR,SER.SOCKET2 RW 280
17 A33 SPARE_D_IN_HIGH
20A ILL.LAMP OrW 150 150 W 306
18 B02 WIPER RY
20A HEAD LAMP G 180 2.0 180
19 B01 BUZZER
10A BACK.STOP LAMP Or 190 154 GW 671
20 B07 SPEED PULSE_TCU
20A HORN/CONVERTER ROr 210 LW 538
21 A34 NEUTRAL SIG
30A AIR-CON/HEATER 1 L 230 2.0 VW 539
22 B03 ANTI-RESTART RELAY
20A FUEL WARMER Gr 250 1.25 V 467
23 B12 ELEC. STEERING PUMP RELAY
30A CIGARLIGHTER G 260 260 Y 423
24 A32 RIDE CONT. ON
W 112 8.0 210 BrW 424
A22 RIDE CONT. AUTO
280 G 993
A07 CAN(1)-H
20A SERVICE SOCKET 1 R 270 270 V 994
25 A17 CAN(1)-L
20A SPARE B 995
26 A04 CAN_SHIELD(GROUND)
20A WORK LAMP_REAR Y 140 2.0 R 672
27 B26 BRAKE OIL LOW PS
20A WIPER Br 300 VW 675
28 B37 PARKING OIL LOW PS
20A PARK, PILOT CUT ROr 340
29 B16 SPARE_D_OUT_HIGH
10A JOYSTICK-DETENT V 360 360
30 B39 BOOM DOWN PR SNENSOR
30A PRE-HEAT, FUEL WARMER Y 370 440
31 B29 BOOM UP PR SNENSOR
20A FAN REVERSE, ATT. LW 390 R 394
32 B04 REVERSE FAN CONTROL
10A RIDE CONTROL WOr 420
33 B21 DIFFERTIAL LOCK PR SIGNAL
10A JOYSTIC_SWITCH Gr 440 Br 680
34 A03 +24V PRESSURE SNESOR
112 LW 705
B25 FUEL SENDOR
Y 112A 8.0 112A W 710
B35 HYD TEMP SENDER
103 ROr 715
B36 ALT LEVEL
G 720
B10 COOLING FAN EPPR-
20A TURN LAMP GW 500 V 721
1 B20 COOLING FAN EPPR+
5A CASSETTE/ROOM LAMP Gr 520 B 730
2
30A START KEY SWITCH R 530 2.0 570 YW 725
3 A36 AIR FILTER
10A TCU 24V BATTERY ROr 600 600 WOr 690A 690
4 B11 GROUND_SENSOR
20A ECM 24V BATTERY W 610 2.0 B 655
5 B17 TACHO SENSOR(+)_REMOTE FAN
20A MCU 24V BATTERY GW 630 230 W 656
6 B18 TACHO SENSOR(-)_REMOTE FAN
20A AIR-CON/HEATER 2 BrW 240 2.0 240 B 730
7 B24 SPARE_ENGINE COOLANT TEMP
10A CLUSTER 24V BATTERY Gr 650 G16
8 B13 SPARE_PREHEATER RELAY
520
A05 SPARE_DIGITAL INPUT_LOW
3R 103 160 L 790
A18 CAN2 LOW
590 Y 791
A08 CAN2 HI
LOr 303
A23 WIPER INT SIG
610 Gr 305
A31 WASH SIG

7-3
621
A38 SPARE_DIGITAL INPUT_LOW
L 380
B14 FUEL WARMER
Y 620 Gr 235
A35 AC CONDENSOR FAN SIGNAL
20A ECM_IG Br 621 W 234
9 B15 AC COMP. OFF SIG_REVERSE FAN
Gr 550 630 Or 233
A16 BLOWER RUN SIGNAL_DINP
10A MCU BW 560 560
10 A24 SPARE_HIGH SOURCE
A26 SPARE_LOW_ENGINE OIL LOW
10A TCU Or 570 570B
11 B40 BOOM POSITION SENSOR
570C
B30 BUCKET POSITION SENSOR
10A CLUSTER V 580 580 BrW 740
12 A01 REF. POWER +5V
650
A37 MECHANICAL ENGINE SELECT
10A CASSETTE LW 590 BW 560
13 A11 POWER IG(+24V)
A12 BATTERY POWER(+24V)
10A SPARE GW 630
14 A02 BATTERY POWER(+24V)
LOr 154
B09 DETENT CONTROL_BUCKET
5A ILLUMINATION 1 YOr 160 160A
35 B08 DETENT CONTROL_BOOM UP
390
B19 DETENT CONTROL_BOOM DOWN
5A ILLUMINATION 2 Or 170 170
36 A30 COUNT_WEIGHT_SET SWITCH
A39 SPARE_ENGINE SPEED SENSOR
BrW 740
A29 SPARE-DIGITAL INPUT-LOW
WOr 690B
A40 SPARE_SPEED PULSE
CS-55 LOr 754
B31 TM MODE SELECT SIG
B G21 BW 755
12 B28 CLUTCH CUT OFF_SLT SIG
2 1 BW 261
2 B32 ENGINE POWER MODE SELEET
Y 423 BrW 740
10 B22 SPARE_PR SIGNAL
4 Br 217 WOr 690
8 9 B05 SPARE_HOUR METER
10 8 B06 SPARE_D_OUT_HIGH
3 WOr 690C
7 A28 SPARE-DIGITAL INPUT-LOW
7 6 WOr 420
6 B33 SPARE-DIGITAL INPUT-LOW
9 423 RW 770
B23 REVERSE FAN MODE-ON
BrW 424 424 GOr 771
4 B34 REVERSE FAN MODE-AUTO
LOr 421
3 A15 BOOM POSITION SELECT SIGNAL
Or 170F

RIDE CONTROL SW
1 A25 BUCKET POSITION SELECT SIGNAL
12 11 W 780
11 A27 PROGRAM DUMP
R 781
A19 RS-232(1) RX
CS-17 Br 782
A09 RS-232(1) TX
B G21B WOr 757
12 A21 RS-232 GND

12
Or 170B Br 758
11 A10 RS-232(2) TX
R 759
10 A20 RS-232(2) RX

10
8
9 CN-134 A06 SPARE-DIGITAL INPUT-HIGH

4
ROr 340C Or 570A
8 1

9
ROr 340B Or 800
7
7 2 CN-58B

3
W 801
4
3
LW 350 CN-157
DIAGNOSTIC

4 6

PARKING SW
Y 352 B G17
3 1 VM1-GND
G17A
TCU

1 2 VM2-GND 14
11

12
Or 800
15 SDDK-DIAGNOSTIC 16
W 801
18 EUPR-DIAGNOSTIC 33
Or 570A
6 NC 34
Y 352
21 ED10-PARKING BRAKE SW(+) 35
66 ED9 DIFF. LOCK SWITCH 40
29 ED11 47
G 993
25 CANF_H 48
V 994
26 CANF_L 50
B 995 995
28 VGS-CAN SHIELD 53
GW 671
36 SD4-SPEED METER CLUSTER 54
600A
23 VPE1-CONTINUANCE 24V 58
ROr 600 600
68 VPE2-CONTINUANCE 24V 60
Or 570 570
45 VPI-POWER IG 61
B 810 810
3 VMG1-SPEED PICK-UP COM 27
W 820
19 EF1-SPEED PICK-UP ENG
B 810A
27 CANF_T
RW 825
CN-125 41 EF2-SPEED PICK-UP TURBIN
GW 630 B 810B 850A
BATTERY(+) 1 12 VPS1-GEAR BOX VPS1(+)
BW 560 WOr 830
KEY IG(24V) 2 42 EF3-SPEED PICK-UP GEAR
UNIT

G 840
NC 3 4 VMG2-SPEED SENSOR OUTPUT
R 759 V 845
SERIAL "1"_L(RX) 4 62 EF4-SPEED SENSOR(SIG)
REMOTE

Br 758 VW 850 850

SERIAL "1"_H(TX) 9 13 VPS1-GEAR BOX VPS1(+)
WOr 757 ROr 855
GROUND 5 17 ER3-SW FILTER RESTRICTION
GOr 860
MANAGEMENT

NC 49 ER2-SENSOR TEMP CONVERTER

B G21 OrW 865
GROUND 12 32 AIP3-GEAR BOX Y3
YOr 870
39 ER1-GEAR BOX TEMP
WOr 875
CR-41 46 VMGA2-GEAR BOX TEMP(COM)
B G19 BrW 880
86 30 87a 51 AIP6-GEAR BOX Y6
LW 743 743 Gr 885
85 55 AIP4-GEAR BOX Y4
YW 890
87 56 AIP1-GEAR BOX Y1
V 360 LOr 895
86 9 AIP5-GEAR BOX Y5
85 87 87a VOr 900
30
VOr 366 10 AIP2-GEAR BOX Y2
VOr 905
BOOM UP RY

20 ED3-SHIFT LEVER-X1A-B3
CR-40 BrW 910
43 ED4-SHIFT LEVER X2B-FWD
86 30 87a ROr 915
OrW 746 746 63 ED1-SHIFT LEVER X1C-B1
85 LW 920
B G19 64 ED5-SHIFT LEVER X2C-REV
87 GrW 925
V 360 65 ED2-SHIFT LEVER X1B-B2
86 GOr 930
85 87 87a 67 ED6-SHIFT LEVER X2D-NEU
30
GrW 365
WOr 451A 451
BUCKET RY

22 ED7-SHIFT LEVER-X1D-KD
DO-5 RW 935
7 ADM2-JOYSTICK SELECT LAMP(-)
1
GrW 365 WOr 449
CAN BUS

31 ED13-REV-JOYSTICK
2
V 360 DO-4 LOr 447
30 ED12-NEU-JOYSTICK
366 VOr 1 GrW 448
44 ED8-FWD-JOYSTICK
360 V 2 VOr 450
NC 14 59 ED15-JOYSTICK SELLECTER(+)
WOr 451
NC 15
V 360 360 W 426
24V(DETEND) 1 8 VPS2-RIDE CONT. RY(+)
Gr 440 440 R 540
24V(HANDLE) 9 52 ADM1-START INTERLOCK RY(-)
WOr 449 449 G 193
REV 2 5 ADM4-REVERSE DRIVE RY(-)
GrW 448 448 700 L 425
FWD 3 57 ADM5-RY RIDE CONT.(-)
LOr 447 447 945
CN-246

NEUTRAL 4 11 ADM6-RY DIFF LOCK(-)

VOr 450 450 940 L 940
JOYSTICK SELECT 10 24 VMGA1-GROUND_BRAKE PEDAL
WOr 451 451 G 945
KICK DOWN 8 37 AU1-+5V SUPPLY_BRAKE PEDAL
Y 700
BOOM DOWN(-) 7 38 EU1-SIGNAL SENSOR_BRAKE PEDAL
GrW 365 W 426A
BUCKET(-) 6
VOr 366
JOYSTICK LEVER

BOOM UP(-) 5
COUNT_WEIGHT SW16
YW 214B
HORN SWITCH 11
Or 170D
ILLUMINATION 12
B G19
FNR SWITCH 13
CN-160
8.0
8.0
5.0
L

Y
W

280
270
210
260

B G21
L
B

Y
B
B
B
V
V
V
V
B
V
Y
B
V

R
R
R
R
R
R
R

G
G
G
G
G

W
W
W
W
W
W
W
W
W
W
W

Br
Br
Br

Gr
Or
Or
Gr
Or
Or
Gr

LW
LW
LW
LW

YW
VW
VW
YW

RW
RW
LOr
RW
RW
RW
RW

GW

VOr
YOr
YOr
YOr

ROr
ROr

GOr
GOr
GOr

BrW
BrW

OrW
WOr
WOr
OrW
WOr
OrW

B G19
EARTH
GOr 534
531
530
531
890
900
865
885
895
880
850
870
860
855
875
531
2LW 381
350
112
112
112
112
103
112
112
202
675
672
700
610
621
830
825
820
810
845
840
945
940
746
743
360
660
661
211
462
715
705
725
710
721
720
730
680
394
141
506
505
170
390
184
187
740
BrW 191
LOr 200
535
216
422
237
245
242
373
371
372

656
655

810B
810A
570B
440A
690A
160A
426A
995C
994C
993C

B G22
B
B
B
B
B

R
R
R
2.0

G
Or
3.0
3.0
3.0
3.0
3.0
3.0
3.0

RW

B G20
3
3

9
8
7
6
9
8
7
6

4
1
4
1

5
5

2
2

280
270
220
ROr 210
260
220
WOr 690
BW 261
BrW 740

G20
G20
G22
48
47
46
45
44
43
36
41
40
39
38
37
32
35
34
33
42
31
30
29
28
27
26
25
24
23
22
21
20
14
13
15
17
16
19
18
12
11
10
13
60
20
44
26
56
55
54
53
52
51
50
49
48
47
46
45
43
42
41
36
29
37
22
21
23
24
33
35
34
32
31
30
58
28
27
57
25
38
40
39
59
19
18
17
16
15
14
12
11
10

CN-5
CN-6

170E

G22B
G22A
NC
NC
NC
NC
NC
NC
NC
NC
NC
NC

NC
NC

1
HORN

2 2
2
2

1 1
1
5
4
2

6
1
3

A
B
C
SHIELD

CS-2

CL-2
PARKING

CN-139
AC R/DRY
AC R/DRY

TUU_GND

CN-172
AC COMP.

TCU_(5V+)

CN-171
CS-80

B
FUSE MAXI
FUSE MAXI
FUSE MAXI
FUSE MAXI
FUSE MAXI
FUSE MAXI
FUSE MAXI
ECM-J1939-

STOP LAMP

REAR LAMP
ECM-J1939+

CN-138
1
SENSOR_24V

0, I
12V
24V
START RELAY

TUN LAMP_LH

2.5
FUEL SENDER
BACK BUZZER

TUN LAMP_RH

GND

SERVICE
MAIN PUMP PS
ALTERNATOR I
GROUND_MCU
HEAD LIGHT HI

SERVICE
GEAR BOX - Y1
GEAR BOX - Y2
GEAR BOX - Y3
GEAR BOX - Y4
GEAR BOX - Y5
GEAR BOX - Y6
FUEL WARMER
ATT. LOCK SOL

PILOT CUT-OFF
ECM POWER IG
DIFF. LOCK SOL

REF. POWER 5V

GEAR BOX TEMP

SOCKET SOCKET
HEAD LIGHT LOW
PRE-HEAT RELAY

ATT. UNLOCK SOL

ECM BATTERY 24V

ECM-J1939 SHIELD

GEAR BOX VPS1(+)

TEMP CONVERTER
HYD TEMP SENSER

12V
STEERING PUMP PS
RIDE CONTROL SOL.

4
FAN SPEED SENSOR
FAN SPEED SENSOR

SPEED SENSOR_24V

FILTER RESTRICTION
SENSOR_STOP LAMP
JUMP WIRE-JOYSTICK
AIR CLEANER SWITCH
BOOM UP PR SENSOR
ECM-AIR HEATER OUT

H0 I
BATTERY RELAY(DO-1)
SEERING PUMP RELAY
SEERING PUMP RELAY

GEAR BOX TEMP(COM)

SPEED SENSOR_VMG2

3
2

6
5

V
SPEED SENSOR_EF4(2)

24V
PRO-PORTIONAL VALVE
PRO-PORTIONAL VALVE
PRO-PORTIONAL VALVE

H
PROXIMITY SWITCH_24V

C BR ACC
BOOM POSITION SWITCH

TURBIN PICK-UP SENSER

TURBIN PICK-UP SENSER
FAN REVERSAL SOL _24V

BOOM DOWN PR SENSOR

ENGINE PICK-UP SENSOR

ENGINE PICK-UP SENSOR
ECM-AIR HEATER RETURN

BUCKET POSITION SWITCH

FAN PROPORTIONAL VALVE
FAN PROPORTIONAL VALVE
REAR COMBI_ILLUMINATION
REAR COMBI_ILLUMINATION

INTER GEAR PICK-UP SENSOR

INTER GEAR PICK-UP SENSOR
FAN REVERSAL SOL CONTORL

PRESSURE SENSOR_JOYSTICK

CLUTCHBRAKE PEDALSENSING
24V_SENSOR-CLUTCH CUT-OFF

BRAKE OIL PRESSURE SENSING

DIFFERENTIAL SHIFT PR SENSOR

PARK BRAKE PRESSURE SENSING

RIDE CONTROL PRESSURE SENSOR

12V SOCKET
SWITCH

CIGAR LIGHTER
SWITCH
START KEY

FRAME HARNESS
DC/DC CONVERTER
ECONO MODE

7309S7EL01
·ELECTRICAL CIRCUIT (2/2)

OFF IDLE
5
USB PLAYER POWER CONNECT SUB CONNECTOR

LINEAR THROTTLE
CN-99
3 990A AUTO REVERSE FAN
A A EMERGENCY TEST
991A

REMOCON GND
12
12
CN-162 RESISTOR 12

5
B 4 3

SPK FRT RH+

2

SPK FRT LH+

SPK FRT RH-
THROTTLE

SPK FRT LH-

G 647

REMOCON+
6 C B CN-20 0,2

BACK UP+
TEL MUTE

AUX_GND
ASSEMBLY

USB GND
YOr 646 G56

ANT 12V
CN-93

USB D+
1

USB 5V
5 2

USB D-

AUX_R
AUX_L
Or 645 YOr 646 213

GND
ACC

ILL+
4 1 OFF IDLE SW 1 2 0 1

CN-27A
ILL-
NC

NC

NC

NC
GW 644 Or 645

11
4

CN-27
CS-75
11

1
CS-73

3
4
6 10

9
3 11 ON IDLE SW 8 7
ON IDLE L 643 W 642 HORN

10
11
12

11
10
12

10
11
12
13
14
15
16
2 CN-25

9
4

8
1
2
3
4
5
6
7

1
2
3
4
5
6
7
1
3

3
1
23 ACCEL POSITION RETURN
6 W 642 L 643 G56A
1 9 ACCEL POSITION SIGNAL 2

WOr

OrW
GW 644 213A

GOr
YOr

RW

LW
RW
22 ACCEL POSITION SUPPLY 1

WOr

Or
BW
GOr

W
Gr

R
B
B
G 647
CN-6 34 SWITCH RETURN
G 990 G 990 213
ECM-J1939+ 7 46 J1939(+) CL-3
V 991 V 991 179
8

G60D

G60C
Lo

G60E
ECM-J1939- 47 J1939(-) 6

163C

163B

163A
B 992 B 992 189A

G60

G60
774

696

775

461

591

523
524

521
163

525

526

513
514
515
516

517
518
519
ECM-J1939 SHIELD 9 37 J1939 SHIELD 4 Hi
RW 375 RW 375
PRE-HEAT RELAY 10 40 AIR-HEATER OUTPUT 5
GOr 374 GOr 374 172 172 SPEAKER
PRE-HEAT RELAY 11 42 AIR-HEATER RETURN 3 C
G56B
1 2 E CN-23

ABL
31 ALTERNATE TORQUE
510 510 526 WOr
2 1 T 1

LH
262 524
3 32 COOLANT LEVEL RETURN 2
262 G
4 28 COOLANT LEVEL CL-4
622 179 179 CS-1
5 39 POWER IG CN-10 6 Lo CN-24
189 189 R 522 525 W
6

RH
23 4 Hi HEAD 1
ECM 523

774

696

775
22 5 LIGHT 2
Br 622 162 162
NC 13 CD-39 CN-94 21 3 C -RH
Br 684 W 611 2.0 611 W G56C DOOR S.W
57 2 E CN-7

ABL
NC A 4 BATT (+) 20

- S+
Or 662 662
Pa 2.0 611A W 509 509 163 YOr
MAIN PUMP PS 56 B 3 BATT (+) 19 1 T CL-1 1 FUSE_ILLUMINATION
WOr 693A 5B G55 2.0 G55B 591 LW
C 2 BATT (-) 18 3 3 FUSE-CASSETTE
2.0 G55A Gr 521A 521 Gr
MAIN PUMP PS 1 BATT (-) 17 2 4 FUSE_ROOM LAMP
WOr 694 G60I 696 WOr
7 CN-100 1 5 MCU_RETURN
Gr 466 CN-29 2
GOr 510 742 742 BrW 774 RW
SEERING PUMP RELAY 52 2 1 B ROOM LAMP 7 MCU_REVERSE_MANUAL
R 463 R 243 Or 172 694A 775 GOr
SEERING PUMP RELAY 53 3 2 Pa 3 3 E 8 MCU_REVERSE_AUTO
V 663 V 238 R/DRY OrW 509 745 745 LW
4
W 132
STEERING PUMP PS 55 1 1 4 S LH 1 9 NC
Or 662 YOr 179 G61
MAIN PUMP PS 56 5 CD-1 5 BOOM KICK OUT 2 10 NC
684 W 711 711 R 189 694 WORK
4 2 C 6 CL-5 11 NC
693A 693C YOr 162 LAMP
6 1 1 CN-101 12 NC
W 213 742 FRONT W 132A
CN-19 CD-10 HYD. TEMP 8 1 B 1 13 NC
YW 726 726 BrW 742 694 G61A
Pa 9 3 E RH 2 15 NC
WOr 693 693 LW 745 748 748 1.25 146 RW
10 4 S CL-6 2 NC-NC
OrW 748 W 132 1.25 142 RW
AIR-CLEANER CD-2 11 BUCKET LEVELER 6 WORK LAMP RELAY
B 657 693D B G56 1.25 1.25 132 W

WORK LAMP FR
FAN SPEED SENSOR_MCU 24 1 12 14 WORK LAMP RELAY
W 658 LW 706 706 B W 133 W 133
FAN SPEED SENSOR_MCU 23 2 13 CD-41 1
R 243 Or 432 695 G62

G57
AC RELAY 14 14 1 Pa 2

S S + -
V 238 FUEL SENDER OrW 646 433
AC RELAY 16 CN-154(GRAY) 16
RIDE CONTROL 2 BOOM DOWN CL-35
W 711 G 722 722 Br 432 645
MCU_HYD TEMP SENSER 46 2 15 3 P./SWITCH

1.25
YW 726 V 723 723 W 133A
MCU_AIR CLEANER SWITCH 47 1 4 1
B 731 432 Or 433 G62A
FAN PROPORTIONAL V/V CN-155(BLACK) 1 2

OPTION
LW 706 LW 391 391 646 OrW 645
MCU_FUEL SENDER 48 2 2 CN-136 CL-36
G 722 R 393 393 432 Br 432 432
MCU_FAN PROPORTIONAL VALVE 42
V 723
1
G57
3
G58 G58
2 RIDE SOL RW 142 RW 142

WORK LAMP RR
MCU_FAN PROPORTIONAL VALVE 43 FAN REVERSE SOL 4 1 CONT.VALVE 1
B 731 CD-73 694 WOr 695 G63
MCU_SHIELD 41 5 2
R 393 657 B RW 146
FAN REVERSAL SOL CONTORL 29 1 FAN PICK-UP 6 CL-32 CN-9
LW 391 658 W 1.25 133 W
FAN REVERSAL SOL _24V 30 2 CN-141 2 WORK LAMP RELAY
BrW 192 RW 142A 461 BW 1
BACK BUZZER RELAY 40 1 EMERGENCY RELAY
LOr 201 G63A 330 Br
STOP LAMP RELAY 39 2 3 FUSE-WIPER
CN-250 CN-249 336 OrW
NC_RELAY_WORK LMAP 33 CN-14 CN-14 CL-33 4 WASHER TANK
YOr 161 B 607 606 B 613 613 331 RW
FUSE_ILLUMINATION 31 2 1 1 1 SHD 5 REAR WIPER MOTOR
GOr 508 V 609 607 B 612 612 334 G
TURN LAMP_LH 35 4 2 2 2 GND 7 REAR WIPER MOTOR

WORK LAMP REAR

Or 171 B 606 608 W 615 615 RW 146 L 252
FUSE_ILLUMINATION 32 1 3 3 3 SIG 1 9 MIRROR HEAT CONT.
OrW 507 W 608 609 V 614 614 G72
TURN LAMP_RH 34 3 4 4 4 24V 2 6 NC
5 5
CAMERA CL-22 14 NC
253 V
6 6 10 MIRROR HEAT CONT.
WOr 693 RW 146
GROUND_MCU 45 CN-10 1 11 NC

336

253
330
334

331
Br 684 161A G72 121 WOr
MCU_24V 36 1 12 12 2 12 FUSE_BEACON
508A 2 CL-23 13 NC
171A
3 15 NC
507A R 122
4 2 8 NC
YOr 185 185 B G70 1.25 G70 B G71 BEACON M G64B
MULTI_HEAD LIGHT LOW 28 5 11 11
LAMP 1
R 188 188 B G54 2.0
MULTI_HEAD LIGHT HI 27 6 CL-21 CR-39 CL-7
693B 171B Or 174 174 FROM BATT. RY
7 10 10 2

519

513
518
517
516
515
514
W 212 212 G71 465 L 252

G60M
54

G60N
HORN 8 1 2

G60L
G60J

YOr 163H

YOr 163K
RH

YOr 163J
BrW 741 741 464 G64

334

331

OrW 336

330

253

122

WOr 121
26 CN-65
MCU_REF. POWER 5V
MCU_BOOM POSITION SENSOR 44
LW 744 744
9
10
G54
1
NUMBER PLATE LAMP
CN-19 M CN-150
1

BACK BUZZER MIRROR

OrW
OrW 747 747 BrW 192 192

GOr
MOTOR RY

RW

RW
LW
MCU_BUCKET POSITION SENSOR 20 11 2 5

Or
Br

W
G
HEATER

R
B

B
Gr 465 L 252A
50 12 2 2

CS-76

CS-23

CN-27B
CS-35
R 464 LH G64A
51 13 CL-16 CD-40

3
1

3
1

3
1

2
1
3

5
4
3
ATT. UNLOCK SWITCH 1

10

10
9

10
9

8
12

12

12
11

11

11

10
571 Or 171 687 687

G62
G61

G64
G60
14
171 Br
A Pa

- S+
Br 430 430 OrW 507
4 C
REAR 4
664
CN-149 1 10 3 11 1 8 7 11 1 8 7 11
507 V 664 I 0
RIDE CONTROL RELAY 17 15 3 T COMBI 1 B

USB +(5V)
OrW 647 647 G54D 695 695

AUX GND

USB GND
RH WOr
RIDE CONTROL RELAY 18 16 6 C

USD D+
2 E

AUX S2
AUX S1

USD D-
LOr 201 201 G63
17 1 S
ELEC. STR PUMP PS G72 0,I
18 CL-15 12 5 8 12 12 10 4 9 3 12 12 10 4 9 3 12
YOr 161 161 C
NC 38 19 4
REAR
GOr 508 508 REAR WIPER SW MIRROR HEATER SW BEACON SW USB PORT
NC 37 20 3 T
COMBI
G54E
BOOM UP SENSOR_MCU 21 21
201A
2 E LH EMERGENCY STEERING
BOOM DOWN SENSOR_MCU 22 22 1 S
23 RELAY(HI)
THER_ INCAR AMBIENT FET
NC 59 SENSOR SENSOR
MODE-1 ACT'R MODE-1 ACT'R MISTER(+) TEMP ACT'R INTAKE ACT'R
BLOWER

3
1
NC 58 1 4
2 7
1 4
2 7
1 4
2 7
1 4
2 7
CN-13 CN-96 M M M M

4
2
L 384 2.0 2.0 384 L 5 5 5 5
1 B
L 384A 2.0 B G53 2.0 1.25 G53 B

1
1
5
6
7

5
6
7

5
6
7

5
6
7

4
1
2
3
4

1
2
3
4

1
2
3
4

1
2
3
4

2
3
2
2 A
CN-13 3
FUEL WARMER AC-2 AC-22
Gr 246 246 CN-28

RY
BY

BW

BY
AC COMP. 15 5 12 NC 10 10
Y 376 376 Gr 247 1.25 247
PRE-HEAT RELAY 12 6 5 2 NC 5 5
G 536 536 Y 377 1.25 G53B AC COMP.

2.0

2.0
2.0
6 1

2.0
START RELAY 19 7
G 537 1.25
NC 14 14
ROr 716 716
MCU_ALTERNATOR I 49 8 7
CR-24 CN-80 NC 6 6 CN-11
ROr 717 1.25 961 B BW 2.0 BW
3 8 15W 707 GND 1 1 1 1 1 GND(CONTROLLER)
377 964 YOr RY RY
12 RS-1 TAIL(+) 4 4 4 4 8 ILLUMINATION
382B L ROr 717A 963 RW RW 2.0 RW
1 2 15R 709 PREHEATER BATTERY(+) 3 3 3 3 5 FUSE(Battery)
382A L RESISTOR 3W/300 RW 718 1.25 988 W L L

AC & HEATER CONTROLLER

2 1 REVERSE FAN 13 13 13 13 4 REVERSE_MCU
PREHEATER 962 R 2
R R
IG2 2 2 2 3 FUSE(IG)
ALTERNATOR CN-74 RELAY 965 G RG LY
CR-23 CN-45 ACT'R REF 7 7 7 7 6 DPS(COMPRESSOR)
NC 4 5W 727 968 BW GB YW
SENSOR GND 8 8 8 8 7 CONDENSOR FAN
G53A M
U
FI 3
ROr 717 537
M THERMISTER(+) 9 9
969
966
GW
R
9 9
Y
YL
BR 2 BLOWER_SIGNAL
L 2 5R 728 INCAR SENSOR 11 11 11 11 AIR CON
3
~ P 1
B+ AMBIENT SENSOR 12 12
970 OrW 12 12
YB
G 718 START RELAY
B+ 708
708 15 R STARTER 983 YW YW
CONDENSER FAN 18 18 18 18
109 80R 987 Y 17
LY
COMPRESSOR 17 17 17
FROM BATTERY RELAY 986 LW BY
FET_F/BACK 16 16 16 16
985 YW BR
BLOWER RELAY_LO 15 15 15 15
984 BOr BL
FET_GATE 14 14 14 14
982 LW LW
MODE-2 ACT'R_PBR 12 12 12 12
981 Y LB
MODE-2 ACT'R_FOOT 11 11 11 11
980 LW LR
CD-3 MODE-2 ACT'R_DEF 10 10 10 10
684 Br Br 682 682A BRAKE ACC. PS 979 WOr LgW
A
- S+

3 3 Pa MODE-1 ACT'R_PBR 9 9 9 9
674 978 BW 8
LgB
B MODE-1 ACT'R_FOOT 8 8 8
693 WOr WOr 692 692A 977 Gr 7
LgR
5 5 C MODE-1 ACT'R_VENT 7 7 7
L 941 941 L L 942 976 Y 6
BrW
TCU_VMGA1(24) 60 6 6 TEMP ACT'R_PBR 6 6 6
G 946 946 G W 947 975 G 5
BrB
TCU_AU1(37) 25 9 9 TEMP ACT'R_WARM 5 5 5
974 BOr 4
BrR
TEMP ACT'R_COOL 4 4 4
673 R R 674 973 L 3
LW
1 1 INTAKE ACT'R_PBR 3 3 3
972 BW LB
CD-26 INTAKE ACT'R_REC 2 2 2 2
CN-5 682 971 WOr 1
LR
A Pa
- S+

INTAKE ACT'R_FRE 1 1 1
676 VW VW 677 677 PARKING
4 4 B PS NC 13 13 13 13
Br 662 2.0 692

CN-160
JOYSTICK SELECT 10
16

11
13
14
15
12
AC-1 AC-11

6
5

1
3
2
C

8
FUSE_JOYSTIC SW 9
7
FUSE BOX_IG 16
W 611 2.0
FUSE BOX_IG 17 CD-4
3L 382 942

RELAY_BUCKET
FUEL WARMER REALY 33 7 7 1 Pa

ILLUMINATION
S S + -

RELAY_BOOM
HORN RELAY
947 STOP LAMP

KICK DOWN
2
R 673 203 GW GW 204 204

NEUTRAL
MCU_BRAKE OIL LOW PRESSURE 13 8 8 3 CLUTCH CUT-OFF
VW 676 701 Y Y 702 702

FWD
GND
MCU_PARKING PRESSURE 14 2 2 4

REV
24V
NC

NC
NC

NC
Y 701
TCU_EU1(38) 15
G50B B
10 10
B G51
STOP LAMP &
CLUTCH CUT-OFF PS

363 GrW

442 WOr
11 11

362 VOr
441 Gr
G19 B
12 12

369 V
GW 359 LW LW 351
STOP LAMP RELAY 20 13 13 CN-71
G51
14 14 1
351
SWITCH PILOT CUT OFF 29 15 15 2
LW 359
SWITCH PARKING 30 CN-12 PARKING
NC 31 SHIFT LEVER
NC 42

AD7
AD6
AD5
AD4
AD3
AD2
AD1
CD-46 MONITOR CLUSTER

VM
VP
ED
841 G CN-110

B1
B3
B2
AS
1

R
V
846 V
SPEED SENSOR OUTPUT MULTI FUNCTION SWITCH 1
2 2 1 442
LAMP_JOYSTICK STR SELECTED

2 1
571 Or 2

Y 7
F
NC 34 3

B 5
WB 8
BG 3

BW 2
NC 35 CD-17 G19

4 3
811 B 6
CAMERA 0_INPUT_SIDE

Lo
CAMERA SIGNAL SHILD

1 4 BK- BK+ 3 362

821 W ENG. PICK-UP 5

OUTPUT SIGNAL

O
363

L
2

2 1

L
CAMERA 0_INPUT
CAMERA 3_INPUT
CAMERA 2_INPUT

CAMERA 1_INPUT

\U+f058
PROGRAM DUMP

MIRROR HEATED 5 BO- BO+ 2

PROGRAM DUMP

Lo Hi F
RS232 PC SHILD

B+
C
X1
RS232_SHILED

X2
ILLUMINATION

ILLUMINATION

Or 571 571 CD-27(GRAY) 3

AD5(R) C

D
A

D
C
B

4 3
FUSE_TCU 1 369
CAN2-SHILD

CAN2-SHILD

6 FL- FL+ 1
HIGH BEAM
RS232 RXD
RS232 TXD

G 841 812 BW 2
CAN2 LOW
CAN2 LOW

BATT. 24V

BATT. 24V
BATT. 24V

RS232 RX
RS232 TX

O
RH TURN
TCU_VMG2(04) 2
LH TURN

AD6(N)
1

AD4(F)

O J
G \U+f058

I
GND_B+

CAN2 HI

CAN2 HI
GND_IG

AD1
AD2

AD3
V 846 826 RW 1

BWG C
IG 24V

IG 24V

ED1(VP)

2 1

Hi
TCU_EF4(62)

J
3

AD7(KD)

HO
2
STANDARD

I
GND

N
GND

B 811 CN-114
NC
NC

NC
NC

TCU_VMG1(03)

RW
4

BVi
BY
CN-57

CN-56
TURBIN PICK-UP CD-47(BLACK) FRONT WIPER

Gr
W 821

W
4 3

L
TCU_EF1(19) 5
BW 812 813 BOr

6
2
6
1

3
5

4
14

18

16

14

INTER
11
12
13
16

19

17

13
12
11
17

18

10

19
15

20
10

15

20

TCU_VMG1(03) 6 2
8

6
6

2
1

1
7
4
5

4
3
2

CN-160
D
9

K
RW 826 831 WOr

JOYSTICK SELECT 10
16
11
14
13
12
15

6
5
1
4
3
2
8
FUSE_JOYSTIC SW 9

7
TCU_EF2(41) 7 1 GEAR PICK-UP

CS-11
CS-12
BOr 813
GOr
GBr

CS-5A
RW

SHIFT CLUTCH
RY
B G50 1.25

4
5
2
TCU_VMG1(03)
M

5
8

1
3
Or

Or

4
1

3
2
7
Or

RELAY_BUCKET
R

R
Y

Y
B

WOr 831
L

L
V

CN-60 MODE CUT-OFF

ILLUMINATION

RELAY_BOOM
TCU_EF3(42) 9

HORN RELAY
GOr
YOr
YOr

KICK DOWN
LOr

RW
YW
SWITCH SWITCH

LW
40A 105
B

CS-74
Pf

JOYSTICK STEERING 10

Gr
Or

Gr

Or
5 Lo

153E

251A

Br

Br
4 Hi

NEUTRAL
G

G
R

R
V

GROUND
3R 104 104 3R
G15
G15

G15
G15

L
187
790
791

624

596

594
592

650
650
580

790
791

935

625
626
627

505
506
650
580
153

629
623

JOYSTICK STEERING 11
2
3
1

M10 3R 102 111 15R 106 FUSE MAXI ILL. HEAD LAMP SW WORK LAMP SW
CN-159

CN-158
HAZARD SW

FWD
REV
JOYSTICK STEERING 12

24V
NC

NC

NC

NC
X1

12

12

12
182
184
187
180
214

303
305
314
311
317
300

501
505
506
X2

12

12

12
3R

10
D

D
B
A

B
A
15R

0.5
0.5

4
80A

V
4

4
RW 532

442 WOr

GrW

GrW
WOr
4

VOr
CONT_JOYSTICK_INTPU1

LOr
18

218 YW
M5 CN-95
WOr

GrW
BrW

173 Or

441 Gr
443 Or
RW 541
GOr

ROr

VOr
LW

G23 B

V
3

3
CONT_JOYSTICK_SENSOR(-) 19
570C Or
G
R

3W 111F
L

CR-1

2
21

363
362
369
444
445
446
FUSE MASTER SW
3W 111A 532 80R 107 108

CS-59

CS-42
11

11
451A

11
CS-41

CS-36
CN-21

CS-21

1
7

9
7

9
7
FUSE 22
930
920
910

915
925
905

10
11

11

11
12

12

12

C
B

B
A

A
9

9
6

2
1

6
5

1
3

1
3

1
3

7
3W 111B G50 80R 109
FUSE 25
B

BATTERY

OrW

WOr

WOr
BrW

BrW
3W 111C

GOr

YOr
RW

LOr

LOr
LOr

LOr
VW

BW
LW

FUSE 26 BATT. RY

Or
W

G
R

R
B

B
3W 111D
G15
596

594
592
580

FUSE 27
3W 111E 15R 111 532A
FUSE 28 2
TO STARTER

153D

153A

153B
G50A
G14

G14

G14

G14
307
315

317
310

505
506

501
501

150
182

180
154

153

134
144

154
154

740
754
690

740
755
690
1
NC 23 DO-2
G14 1.25

B G15 1.25

RW 541
START KEY SWITCH 37
3R 102
FUSE 24 KD SWITCH
CN-110 CS-161
CD-48 WOr 442 443 Or FNR
ROr 856 856 1 1
TCU_ER3(17) 39 1 Gr 441C 441A Gr SELECT
B

876B FILTER RESTRICTION 2 2

SWITCH
629 0.5
623 0.5
GBr 624 0.5

795 0.5
790 0.5
791 0.5

935 0.5

625 0.5
626 0.5

251A 0.5

NC 32 2 Pa
570C

WOr 451A

HORN SWITCH FNR SWITCH

307
315

310

627

650
580

GOr 930
LW 920
BrW 910

ROr 915
GrW 925
VOr 905

505
GOr 506

501

214

303
305
314
311

300

YOr 184
187

OrW 150

180
LOr 154

134
WORK LAMP RY_FRONT 46 VW 144

754

BrW 740
BW 755
WOr 690
CD-49 CS-5B
876A CS-160
G15

G15

2 C YW 218 G23 B
580
592
596

580
592
594

GOr 861 861 TEMP CONVERTER 1 12

RW

RW

LOr

LOr
YW
RY

TCU_ER2(49) 40 1
Or

Or

Or

Gr Gr 441B
Br

Br
W

1 2

G
R

R
Y

Y
L

2 2
CN-112 446 WOr
10
37

12

38
39
50

13

14
27

15
16
17
18

21
22
23
24

28
29

30

19

40
41
42
43

45

31
32

33

34
35

WORK LAMP RY_RELAY 47

59

57
60
58
9

7
8

6
1

4
2

3
W
B
V
B

B
V
B
L

16
WOr 876 876 CN-114
CN-250

4
CN-250A

TCU_VMGA2(46) 38 9 VMGA2
WIPER MOTOR-HI&LOW

GrW 363
WIPER MOTOR-LOW

CLUTCH_MODE
YOr 871 871
PROGRAM DUMP 2

TM_SHIFT_MODE
SHIELD_GROUND

HEAD LAMP_LOW
6
1

MIRROR HEATED

FUSE BOX_HEAD
2
4

2
4

WIPER RY_LOW

GND_SENSOR
FUSE BOX_BATT. 24V

5V_POWER
TCU_ER1(39) 41
TCU_ED4-FWD.
WIPER MOTOR-HI

TEMP
TCU_JOYSTCIK STR

FUSE BOX_BATT. IG

HEAD LAMP_HI
MCU & WASHER

B G361 441 Gr
MCU-SERIAL_L

TCU_ED6-NEU.
TCU_ED5-REV.

WIPER RY_HI
FUSE BOX_TCU

6 9

FUSE BOX_ILL
HORN RY

VW 851 851
TCU_ED1
TCU_ED2
TCU_ED3
RS232 P_DUMP

FLASHER_L
RH TURN
MCU-SERIAL_H

FUSE BOX 4 BO- BO+ 3

MCU_INT
LH TURN

5
RS232_TX

FWD REV
RS232 RX

TCU_KD

TCU_VPS1(12,13) 36 7 VPS1(+) 6
RS232 RX 2

VOr 362 444 LOr 7

RS232 TX 2

BrW 881 881

ILL
1 2 3 4 1 2 3 4 7 3
TCU_AIP6(51) 43 6 Y6 5 FL- FL+ 2
LOr 896 896 Y5 ROr 345
TCU_AIP5(09) 3 8 10
44 5 Y5 445 GrW
Gr 886 886 Y2 6 BK- BK+ 1 2 9 8
TCU_AIP4(55) 45 4 Y4
OrW 866 866 Y3 GrW 344 4
TCU_AIP3(32) 46 Y3 1 10
3 Y6 173 Or
VOr 901 901 VOr 11
TCU_AIP2(10) 47 2 Y2 Y4 TWO LEVER 11 12
YW 891 891 YW Y1 1
TCU_AIP1(56) 48 1 Y1

GEARBOX
TO SHEET 1 OF 2

7309S7EL01-1

7-4
MEMORANDUM

7-5
1. ILLUMINATION CIRCUIT
1) OPERATING FLOW
Fuse box [CN-36 (18)] Illumination switch [CS-21 (3)] Switch ON, 1st step
[CS-21 (9)] Work and hazard switch, cluster, monitor indicator lamp ON
[CS-21 (7)] Fuse box [CN-36 (35)] Switch indicator lamp
I/conn [CN-6 (31)]
LH Combi clearance lamp ON [CL-15 (4)]
I/conn [CN-10 (1)] RH Head lamp ON [CN-4 (3)]
Fuse box [CN-36 (36)] Switch indicator lamp
I/conn [CN-6 (32)]
RH Combi clearance lamp ON [CL-16 (4)]
I/conn [CN-10 (3)] LH Head lamp ON [CL-3 (3)]

2) CHECK POINT
Engine Key switch Check point Voltage
① - GND (switch input)
OFF ON ② - GND (switch output) 20~25V
③ - GND (to light)
※ GND : Ground

7-6
 ILLUMINATION CIRCUIT
CLUSTER
R
ILLUMINATION 17

CN-56
MONITOR
R
ILLUMINATION 18

CN-57 FUSE BOX

BEACON 10A
1 15
ILL & HEAD LAMP SW WORK LAMP_FRONT 20A
16
12 11
1
2 MIRROR,SER.SOCKET2 20A
17
OrW OrW ILL.LAMP 20A
3 18
4 HEAD LAMP 20A
19
BACK.STOP LAMP 10A
6 20
6 LOr HORN/CONVERTER 20A
7 21
4
AIR-CON/HEATER 1 30A
R 22
9 9
FUEL WARMER 20A
3
7 23
R CIGAR LIGHTER 30A
11
12 1 B 24
12

CS-21 LOr
WORK LAMP SW HAZARD SW YOr ILLUMINATION 1 5A
35
12 11 11 12
1 1
Or ILLUMINATION 2 5A
3 3 36
4 4
CN-36
LOr
6
6 LOr 7
3
7 7
4 9
8
4
9 9 9 8
3 10
7 10
R R
11 11
12 1 B 1 12
12 12

CS-36 CS-41

CN-6
1
2
3
4
26
27
HEAD LIGHT-LH
Lo 6 3 28
Hi 4
5
29
Or
C 3
B 30
E 2
ABL

YOr YOr
T 1 1 31
CL-3 Or Or
2 32
HEAD LIGHT-RH 3 33
Lo 6 3 4 34
Hi 4
5
YOr 5 35
C 3
E
B CN-10 59
2
ABL

T 1
60 ALL SWITCH INDICATOR LAMP ON
CL-4
3 CN-14
1
REAR COMBI-LH
C 4
YOr 2
T 3
B 3
E 2
S 1
4
CL-15 3 5
REAR COMBI-RH 11
Or
CL-21
NUMBER
C 4 10 2
PLATE
T 3 1
B LAMP
E 2
S 1
CL-16

7309S7EL03

7-7
2. HEAD LIGHT CIRCUIT
1) OPERATING FLOW
Fuse box [CN-36 (19)] Head light switch [CS-21 (6)] Light switch ON, 2nd step [CS-21 (4)]
Multi function switch [CS-11(8)]
Multi function switch MIDDLE [CS-11(7)] I/conn [CN-6 (28)] I/conn [CN-10 (5)]
LH Head light low beam ON [CL-3 (6)]
RH Head light low beam ON [CL-4 (6)]
Multi function switch DOWN [CS-11(6)] I/conn [CN-6 (27)] I/conn [CN-10 (6)]
LH Head light high beam ON [CL-3 (4)]
RH Head light high beam ON [CL-4 (4)]
Cluster high beam pilot lamp ON [CN-56 (5)]
2) CHECK POINT
Engine Key switch Check point Voltage
① - GND (switch input)
② - GND (switch output)
③ - GND (multi function input)
④ - GND (multi function output)
OFF ON 20~25V
⑤ - GND (multi function output)
⑥ - GND (low beam)
⑦ - GND (high beam)
⑧ - GND (passing B+)
※ GND : Ground

7-8
 HEAD LIGHT CIRCUIT

FUSE BOX
ILL & HEAD LAMP SW BEACON 10A
15
12 11
2 WORK LAMP_FRONT 20A
1 16
MIRROR,SER.SOCKET2 20A
3 17
YOr
4 ILL.LAMP 20A
18
G G HEAD LAMP 20A
6 19
6 7 BACK.STOP LAMP 10A
4 20
HORN/CONVERTER 20A
9 9 21
3 AIR-CON/HEATER 1 30A
7 22
12
11 1 FUEL WARMER 20A
1 23
12
CIGARLIGHTER 30A
CS-21 24

YOr ILLUMINATION 1 5A
35
1
Or ILLUMINATION 2 5A
2 36

1 3 CN-36

6 2 4
3 26
R R
HEAD LIGHT-LH 4 27
YOr YOr YOr
Lo 6 5 28
R
Hi 4
5
6 29
Or
C 3
B 7 30
E 2
ABL

YOr YOr
T 1 8 31
CL-3 7 9
Or 32 Or

10 33
11 34
HEAD LIGHT-RH
YOr 12 35
Lo 6
R
Hi 4
13 59
5
YOr
C 3
B
14 60
E 2
ABL

T 1 15 CN-6
CL-4 16
CN-10

4
YOr
YOr
R
G

5
3 8
R
CS-11

CN-56

16

14
19
18
17

13
12
11
10
20

15
8
7
6
5
4
3
2
1

9
8

6
7

1
4
3
2
LAMP_JOYSTICK STR SELECTED
4BWG

W
6
Hi
C

MIRROR HEATED
PROGRAM DUMP
RS232 PC SHILD

ILLUMINATION
Hi Lo

CAN2-SHILD

HIGH BEAM
CAN2 LOW

BATT. 24V
RS232 RX

RS232 TX
B+

RH TURN
LH TURN
C

CAN2 HI
F

IG 24V
L
R

GND
O

GND
L
R

NC

NC
NC
Y 7 Lo

B 5
WB 8

CLUSTER
BG 3

BW 2

MULTI FUNCTION SWITCH

7309S7EL04

7-9
3. WORK LIGHT SWITCH
1) OPERATING FLOW
※ Illumination switch : ON position (1st step)
(1) Work lamp switch ON (1st step)
ILL & head lamp switch [CS-21 (9)] Work lamp switch indicate lamp ON
Work lamp switch [CS-36 (7) → (3)]
Front work lamp relay [CR-3 (2) → (5)] I/conn [CN-7 (14)]
LH Front work lamp ON [CL-5 (1)]
RH Front work lamp ON [CL-6 (1)]
(2) Work lamp switch (2nd step)
Work lamp switch [CS-36 (6) → (4)] Rear work lamp relay [CR-55 (2) → (5)]
I/conn [CN-7 (2)] LH Rear work lamp ON [CL-22 (1)]
RH Rear work lamp ON [CL-23 (1)]
2) CHECK POINT
Engine Key switch Check point Voltage
① - GND (work lamp power input)
② - GND (work lamp power output)
OFF ON 20~25V
③ - GND (front work lamp)
④ - GND (rear work lamp)
※ GND : Ground

7-10
 WORK LIGHT SWITCH

4
FUSE BOX
1
BEACON 10A
RW RW RW 15
RR WORK 1 2 GW WORK LAMP_FRONT 20A
B
LAMP-LH 2 16
CL-22
3 MIRROR,SER.SOCKET2 20A
17
4 ILL.LAMP 20A
RW 18
RR WORK 1 HEAD LAMP 20A
B 5 19
LAMP-RH 2 RW RW BACK.STOP LAMP 10A
CL-23 6 20
HORN/CONVERTER 20A
7 21
AIR-CON/HEATER 1 30A
22
8 20A
FUEL WARMER
23
9 CIGAR LIGHTER 30A
24
10
3 11
SERVICE SOCKET 1 20A
12 25
SPARE 20A
13 26
W W W Y WORK LAMP_REAR 20A
27
FR WORK 1 14
B WIPER 20A
LAMP-LH 2 28
CL-5 15 PARK 20A
29
W CN-7 JOYSTICK-DETENT 10A
30
FR WORK 1 PRE-HEAT, FUEL WARMER 30A
B 31
LAMP-RH 2
FAN REVERSE, ATT 20A
CL-6 32
RIDE CONTROL 10A
33
OPTION JOYSTIC_SWITCH 10A

1 34
CL-35
W W W
1 2 LOr
B
2 ILLUMINATION 1 5A
3 35
FR WORK LAMP
4
W ILLUMINATION 2 5A
1
B 5 36
2
CL-36 6 CN-36
7
CL-32
RW
1 8
B
2
9
RR WORK LAMP
10
RW
1
2
B 11 2 FR WORK LAMP RY
CL-33 12 4 3 2
B
1
13 W
5
Y
14 2
GW 4 5 1
3
15
CR-3
CN-9
1
RR WORK LAMP RY
4 3 2
B
1
RW
5
VW
2
Y 4 5 1
WORK LAMP SW 3
CR-55
12 11
1
Y
2
3
4
VW

LOr
1
6
6 7
LOr
4

9 9
3
7
R
11
12 1
12
B
CS-36

ILL & HEAD LAMP SW

12 11
1
3
4 CLUSTER
R 17 ILLUMINATION
6
6 LOr CN-56
7
4
MONITOR
R R
9 9 18 ILLUMINATION
3
7 CN-57
R
11
12 1
12
B
CS-21
7309S7EL05

7-11
4. STARTING CIRCUIT
1) OPERATING FLOW
Battery(+) terminal Fusible link [CN-60] Master switch [CS-74]
I/conn [CN-5 (24)] Fuse box [CN-36] Start switch [CS-2(1)]
ECM power relay [CR-25(30)]
Power relay [CR-35(30)]

The gear selector lever is neutral position. It is necessary condition before the starting.
※ The gear selector has an output signal which is activated whenever the shift lever is in the neutral
position. This signal can be used to control a relay and prevent engine from starting whenever the shift
lever is not in the neutral position.
(1) When start key switch is in ON position
Start switch ON Start switch [CS-2(2)] I/conn [CN-5(37)] Master switch [CS-74]
Battery relay [CR-1]
Battery relay operating(All power is supplied with the electric component)
Start switch [CS-2 (3)] ECM power relay [CR-25 (30)→(87)]
Fuse box [CN-36 (13)] I/conn [CN-5 (16)]
ECM [CN-93(39)]
Power relay[CR-35(30)→(87)]
Fuse box[CN-36 (10)] MCU[CN-58A (A11)]
(2) When start key switch is in START position
Start switch START [CS-2 (6)] Start safety relay [CR-5 (30)→(87)] I/conn [CN-6 (19)]
I/conn[CN-13(7)] Start relay [CR-23] Starter (terminal B+ and M connector of start motor)

2) CHECK POINT
Engine Key switch Check point Voltage
① - GND (battery B+)

② - GND (fusible link)

③ - GND (start key B terminal)
④ - GND (start key BR terminal)
Running ON 20~25 V
⑤ - GND (i/conn CN-5 (37))
⑥ - GND (start key C terminal)
⑦ - GND (start safety relay output)
⑧ - GND (start key ACC terminal)
※ GND : Ground
※ ECM : Electronic control module
※ MCU : Machine control unit

7-12
STARTING CIRCUIT

2
MASTER SW CN-60
3R 104 3R 105
MONITOR CLUSTER 3R 15R 106
CN-95
RW
RW FUSIBLE LINK

CAMERA 0_INPUT_SIDE
FUSE BOX USB PLAYER POWER CONNECT
10A BEACON CS-74 BATTERY RY

CAMERA 0_INPUT
15 RW 80R

REMOCON GND
20A WORK LAMP_FRONT

SPK FRT RH+

16

SPK FRT LH+

SPK FRT RH-
SPK FRT LH-
HIGH BEAM

REMOCON+
BATT. 24V
BATT. 24V
BATT. 24V
20A MIRROR,SER.SOCKET2

RH TURN

BACK UP+
TEL MUTE
LH TURN
17 1 B 80R BATTERY

ANT 12V
IG 24V
IG 24V
20A ILL.LAMP
18

GND
ACC
2

ILL+
CR-1

ILL-
CN-127

NC

NC

NC
20A HEAD LAMP

CN-250A

CN-56
CN-57
CN-250
19
10A 3 DO-2 1
BACK.STOP LAMP RW

10
11
12
13
14
15
16
8
5

1
2
3
4
5
6
7

9
2

4
3
2
3

1
1

4
3
2
4

4
20 2
20A HORN/CONVERTER 14 B
21 1
30A AIR-CON/HEATER 1 15

LW
22 STARTER
V

V
20A FUEL WARMER
23
16
M
24
30A CIGAR LIGHTER
17 M
W START RY
21 5W
B B+
22
20A SERVICE SOCKET 1 G CN-45
25 5R
20A SPARE. 23
26
20A WORK LAMP_REAR 24 CR-23
27
20A WIPER 25 CD-46 R ALTERNATOR
28
20A PARK
29 26 1 B+
G
10A JOYSTICK-DETENT 2 ~
30 27 Or 1 P
30A PRE-HEAT, FUEL WARMER 3 ROr L 3
2
31 28
20A FAN REVERSE, ATT 3 FI U
32 36
10A RIDE CONTROL 4 NC
33
10A JOYSTIC_SWITCH 37 CN-74
34
38
RESISTOR
Y RW
CN-5 5 1

CN-7
ROr 3W/300

3
1

4
2
2
RS-1
20A TURN LAMP
1
5A CASSETTE/ROOM LAMP
2 1 1
30A START KEY SWITCH R
3
10A
2 2
TCU 24V BATTERY
4
20A ECM 24V BATTERY 3 3
5
20A MCU 24V BATTERY 4 4
6
20A AIR-CON/HEATER 2
7 5 5
10A CLUSTER 24V BATTERY
8 6 6
32 COOLANT LEVEL RETURN
19 G
7 28 COOLANT LEVEL
3R
20 8 39 POWER IG
CN-93
21 11
ECM
22 12 CN-94
W
23 CN-13 4 BATT (+)
W
24 3 BATT (+)
2 BATT (-)
25
20A ECM_IG Br 1 BATT (-)
9 26
Gr
46
10A MCU BW
10
47
10A TCU Or 48
11
49
10A CLUSTER V
12 59
X2
60
V AD5(R) C
10A CASSETTE LW D
13 AD4(F) B
C
CN-6
B AD6(N) D
10A SPARE B
14 A ED1(VP) A
CN-159 X1
5A ILLUMINATION 1 AD7(KD) D
35
8 3 AD1 C

5A ILLUMINATION 2
AD2 B
36

GOr
ROr
VW
BW
RW

4
LW
GOr

RW

Or

Or
6 AD3 A

BW
R

R
CN-36
RW

RW

GOr

AD7
VW
LW

LW
Gr

G
R

R
Y
B

Or
Or

CN-134
CN-58A

CN-157

CN-125
CS-2
R

68
45

ADM1-START INTERLICK RY(-) 52

63
64
65
67
22
7 AS AD6

3
8

7
A11
A34
ANTI-RESTART RLY B03
B36

12
1

3
4

5
2

9
1
2
3
4
5
6
3

2
6
5
4

R AD5

ED6-SHIFT LEVER X2D-NEU

VMG1-SPEED PICK-UP ENG

ED5-SHIFT LEVER X2C-REV

ADM2-JOYSTICK SELECT LAMP(-)

ED7-SHIFT LEVER-X1D-KD
CR-38

CR-5
CR-35

CR-25

ED1-SHIFT LEVER X1C-B1

SERIAL "1"_H(TX)
ED2-SHIFT LEVER X1B-B2
VPE2-CONTINUANCE 24V

SERIAL "1"_L(RX)
B DIAGNOSTIC V AD4
87a 85 87 86 30 87a 85 87 86 30 4 1 5 2 3 87a 85 87 86 30

VPS2-RIDE CONT.RT(+)
POWER IG(24V)

0, I
1

B3 AD3

BATTERY(+)
KEY IG(24V)
NETURAL SIG

87a 87a 4 87a

GROUND

GROUND
B2 AD2
ALT LEVEL

VPI-POWER IG
30 87 30 87 2 5 30 87 B1 AD1

NC
NC
86 85 86 85 3 1 86 85
H 0 I II
4 3 2 1 4 3 2 1 4 3 2 1 ED
4
6
5

3
2

H
C ST ACC BR REMOTE N R F
K VP
POWER RY ECM POWER RY NETURAL RY SAFETY RY START SWITCH MANAGEMENT D VM
OUTPUT SIGNAL
MCU
TCU UNIT SHIFT LEVER 7309S7EL06

7-13
5. CHARGING CIRCUIT
When the starter is activated and the engine is started, the operator releases the key switch to the
ON position.
Charging current generated by operating alternator flows into the battery through the battery relay
(CR-1).
The current also flows from alternator to each electrical component and controller through the fuse
box.
1) OPERATING FLOW
(1) Warning flow
Altermator [CN-74 (2)] I/conn [CN-13 (8)] I/conn [CN-6 (49)] MCU [CN-58A (B36)]
Cluster charge warning lamp ON
(2) Charging flow
Alternator Starter [CN-45 (B+)] Battery relay [CR-1]
Battery(+) terminal Charging
Fusible link [CN-60] Master switch [CS-74] I/conn [CN-5 (24)]
Fuse box [CN-36)]
Fusible link [CN-95] I/conn [CN-5 (21, 22, 25~28)] Fuse box [CN-36]

2) CHECK POINT
Engine Key switch Check point Voltage
① - GND (battery)
② - GND (battery relay)
③ - GND (alternator B+)
OFF ON 20~28V
④ - GND (alternator 2)
⑤ - GND (MCU)
⑥ - GND (fuse box)
※ GND : Ground
※ MCU : Machine control unit

7-14
 CHARGING CIRCUIT

6
MASTER SW CN-60
3R 104 3R 105
3R 8W 106
CN-95
RW
FUSE BOX FUSIBLE LINK
10A BEACON
15
20A WORK LAMP_FRONT CS-74
16
20A MIRROR,SER.SOCKET2
17
20A ILL.LAMP
18
20A HEAD LAMP
19
10A BACK.STOP LAMP BATTERY
20 BATTERY RY
20A HORN/CONVERTER 1 RW
21 80R
30A AIR-CON/HEATER 1 2
22
20A FUEL WARMER
6 B 80R
3
23
30A CIGAR LIGHTER
1
24 4 CR-1
W 2
21

20A
22
SERVICE SOCKET 1
25
20A SPARE.
23
26
20A WORK LAMP_REAR 24
27
20A WIPER 25 RW
28 2
20A PARK
B
29
26 1

30
10A JOYSTICK-DETENT
27 DO-2
30A PRE-HEAT, FUEL WARMER
31 28
20A FAN REVERSE, ATT
32 36
10A RIDE CONTROL
33
10A JOYSTIC_SWITCH
37
34
38
Y 47
48

20A TURN LAMP

CN-5
1
5A CASSETTE/ROOM LAMP STARTER
2
30A START KEY SWITCH M
3
10A TCU 24V BATTERY
M
4 START RY
20A
5
ECM 24V BATTERY 5W
20A
B+
MCU 24V BATTERY
6
20A 5R CN-45
AIR-CON/HEATER 2
7
10A
8
CLUSTER 24V BATTERY
CR-23 3
3R
R ALTERNATOR
1 1 B+
~ G
2 2 1 P
ROr L 3
2
3 3
3 FI U
4 4
46
4 4 NC
5 CN-74
20A ECM_IG
9 47 6
RESISTOR
48 7 RW
10A MCU 1
10 ROr 3W/300
49 8 2

10A TCU 50
RS-1
11 CN-13
59
10A CLUSTER
12 60

10A
CN-6
CASSETTE
13
ROr

14
10A SPARE 5
CN-58A

5A ILLUMINATION 1
B36

35

5A ILLUMINATION 2
36

CN-36
ALT LEVEL

MCU

7309S7EL07

7-15
6. ELECTRIC PARKING CIR
CIRCUIT
CUIT
1) OPERATING FLOW
(1) Parking OFF
Fuse box[CN-36 (29)] Parking switch OFF [CS-17 (8)→(4)] I/conn [CN-5 (30)]
I/conn [CN-12 (13)]
OFF ON
Parking solenoid ON (activated)

P
Parking brake released (by hydraulic pressure)
[CS-17 (7)→(3)] T/M control unit[CN-157 (21)]
(2) Parking ON
Fuse box [CN-36 (29)] Parking switch ON Parking solenoid [CN-71] OFF
Parking brake applied [By spring force]

2) CHECK POINT
Engine Key switch Check point Voltage
① - GND (parking switch input)
Running ON ② - GND (parking switch output) 20~25V
③ - GND (parking solenoid)
※ GND : Ground

7-16
 ELECTRIC PARKING CIRCU
CIRCUIT
IT

FUSE BOX

ILLUMINATION 1 5A
35

Or
CS-17 1 ILLUMINATION 2 5A
36
B
12
12

Or
1

11 SERVICE SOCKET 1 20A

10 25
10

SPARE 20A
26
8

9
ROr
4

WORK LAMP_REAR 20A

8 27
ROr
9

7 WIPER 20A
7

28
3

ROr PARK 20A

29
LW V JOYSTICK-DETENT 10A
4 30
Y PRE-HEAT, FUEL HEATER 30A
3 31
1 FAN REVERSE, ATT 20A
11
12

32
RIDE CONTROL 10A

PARKING SW 2 10A
33
JOYSTIC_SWITCH
34
BOOM UP RY
B
86 30 87a CN-36
LW
85
87
V
86
85 87 87a VOr
30 TCU
CR-41 1 VM1-GND
BUCKET RY 2 VM2-GND
86 30 87a 15 SDDK-DIAGNOSTIC
OrW 18 EUPR-DIAGNOSTIC
85
B Y
6 NC
87 21 ED10-PARKING BRAKE SW(+)
V
86 66 ED9 DIFF. LOCK SWITCH
85 87 87a GrW
30
Y 37 AU1-+5V SUPPLY_BRAKE PEDAL
CR-40 38 EU1-SIGNAL SENSOR_BRAKE PEDAL

DO-5 CN-157
GrW
1
V
2

DO-4
VOr
1
V
OrW

BrW
LW

LW
Y

CN-160
CN-5

CN-6
16

20
21
25
26
44
45
33
47
48
30

31
32
14

29
13
3

15
1

1
2

NC 14
NC 15
V
24V(DETEND) 1
LW
Y

24V(HANDLE) 9
REV 2
FWD 3
LW

NEUTRAL 4
Y

JOYSTICK SELECT 10
CN-12

CN-10

KICK DOWN 8
10

10
11
12
13

14
15
11
12

7
3

8
9
6
1

7
8
9

2
2

4
5

BOOM DOWN(-) 7
GrW
BUCKET(-) 6
VOr
5
OrW

BOOM UP(-)
BrW
LW
LW

COUNT_WEIGHT SW 16
Y

HORN SWITCH 11
Or
ILLUMINATION 12
B
FNR SWITCH 13
JOYSTICK LEVER

CL-2 3
Or
Y

B
LW
CD-4

CN-71 B
1
2
3
4

BUCKET LEVELER
BOOM KICK OUT

CIGAR LIGHTER
CN-101
CN-100
1

1
3
4

1
3
4
2
Pa

B
E
S

B
E
S

SS + -
STOP LAMP & PARKING SOL
CLUTCH CUT-OFF PS

7309S7EL08

7-17
7. WIPER AND WASHER CIRCUIT
1) OPERATING FLOW
Fuse box [CN-36 (28)] Wiper relay Hi [CR-4 (3)→(4)] Front wiper motor [CN-21 (1)]
Wiper relay Lo [CR-26 (5), (2)]
Multi function switch [CS-12 (6)]
I/conn [CN-9 (3)] Rear wiper & washer switch [CS-35 (3)]
Rear wiper motor [CN-102 (1)]
(1) Front washer switch ON
① Washer switch ON [CS-12(6)→(2)] Front washer [CN-22 (1)] Washer operating
MCU [CN-58A (A31)→(B02)] Front wiper relay Lo
[CR-26 (5)→(3)] Front wiper motor [CN-21 (5)]
Wiper motor operating (low)
(2) Front wiper switch ON
① INT position
Wiper switch ON [CS-12 (6)→(1)] MCU [CN-58A (A23)→(B02)]
Wiper relay Lo [CR-26 (5)→(3)] Front wiper motor [CN-21(5)]
Front wiper motor intermittently operating
② Lo position
Wiper switch ON [CS-12 (6)→(4)] Wiper relay Lo [CR-26 (4)→(3)]
Front wiper motor [CN-21 (5)] Front wiper motor operating (low)
③ Hi position
Wiper switch ON [CS-12 (6)→(3)] Wiper relay Hi [CR-4(3)→(5)]
Front wiper motor [CN-21(4)] Front wiper motor operating (high)
(3) Auto-parking (when switch OFF)
Switch OFF Fuse box [CN-36 (28)] Wiper relay Hi [CR-4 (3)→(4)]
Front wiper motor [CN-21 (1)→(2)] Multi function switch [CS-12 (5)→(4)]
Wiper relay Lo [CR-26 (4)→(3)] Front wiper motor [CN-21 (5)] Wiper motor stop
(4) Rear wiper and washer switch
① Wiper switch ON (1st step)
Wiper switch ON [CS-35 (3)→(8)] I/conn [CN-9 (5)] Rear wiper motor [CN-102(5)]
Rear wiper motor operating
② Washer switch ON (2nd step)
Washer switch ON [CS-35 (3)→(5)] I/conn [CN-9 (4)] Rear washer tank [CN-103(1)]
Washer operating

2) CHECK POINT
Condition Check point
① - GND (front wiper switch power input) ⑥ - GND (wiper relay power input)
Engine : Stop ② - GND (rear wiper switch power input) ⑦ - GND (front washer power output)
Key switch : ON ③ - GND (wiper relay power input) ⑧ - GND (rear washer power output)
Voltage : 20~25V ④ - GND (front wiper motor Lo power input) ⑨ - GND (front wiper motor power output)
⑤ - GND (front wiper motor High power input) ⑩ - GND (rear wiper motor power output)
※ GND : Ground

7-18
WIPER AND WASHER CIRCUIT

WASHER
M

CN-103
CN-22

PUMP
2
1

1
2
OrW
Gr
B

B
SERVICE SOCKET 1 20A
25
20A
1 SPARE
26
WORK LAMP_REAR 20A
2 27
Br Br Br WIPER 20A
3 28
OrW OrW PARK 20A
4 29
JOYSTICK-DETENT 10A
RW RW 30
REAR WIPER SW 5 PRE-HEAT, FUEL WARMER 30A
B 31
12
6
12

FAN REVERSE, ATT. 20A

1

11 G G 32
G
10 7 RIDE CONTROL 10A
33
5

JOYSTIC_SWITCH 10A
RW 8
10 3

8 34
8

9
10 CN-36
OrW
0,I

5 10
I 0

Br 11
3
1 12
11
12

8 13 Y
WIPER RY HI
CS-35 4
B 3 2
2 14
R
1
5
15 Br
2
Br
CN-9 3 4 5 1
CR-4
3
WIPER RY LO
G
4 3 2
W
1
Y
FRONT WIPER 5
Y Y Y
3E 1 2
G LW W
2Pf 2 3 4 5 1
B B
1B 3
L R B CR-26
R 4 W
4 Hi 5
M
5 Lo 6
CN-21
6

5
4

Br
CN-102
1 3E
G
2 2Pf
B
9 3 1B
4
LOr

LW

RW
Gr
Br

Br
G

5 4 Hi
7 6 5 Lo
M
1
REAR WIPER
CS-11
CS-12
CS-5

CN-58A
WIPER INT SIG A23

A31

B02
1
2
3
4
5
6

8
7
6
5
4
3
2
1
HO

RW

BVi
BY

4BWG
Gr

W
G
L

WIPER RLY
Y

6
2
6
1

3
5

WASH SIG
C

Hi
J

C
W

II

II
J

Hi Lo
I
O

B+
C

MCU
F
L
R
O
L
R

Y 7 Lo

B 5
WB 8
BG 3

BW 2

MULTI FUNCTION SWITCH

7309S7EL09

7-19
 HAZARD, TURN AND ROTARY CIRCUIT

11 FUSE BOX
WOr WOr WOr BEACON 10A
12 15
WORK LAMP_FRONT 20A
13 20A
16
MIRROR,SER.SOCKET2
17
14 ILL.LAMP 20A
18
15 HEAD LAMP 20A
19
CN-9 BACK.STOP LAMP 10A
20
HORN/CONVERTER 20A
21
AIR-CON/HEATER 1 30A
22
1 FUEL WARMER 20A
23
2 CIGARLIGHTER 30A
24
3
4 GW TURN LAMP 20A
1
CL-16 33 CASSETTE/ROOM LAMP 5A
2
C 4
OrW START KEY SWITCH 30A
T 3 34 3
E 2
B TCU 24V BATTERY 10A
4
S 1
35 ECM 24V BATTERY 20A
5
36 MCU 24V BATTERY 20A
REAR COMBI-RH 6
59 AIR-CON/HEATER 2 20A
7
CLUSTER 24V BATTERY 10A
60 8
CL-15 CN-6
C 4
GOr CN-36
T 3
B
E 2
S 1

REAR COMBI-LH

FLASHER UNIT
RW
87 L
GW
85 B G
B
86 E
CR-11

CLUSTER
8 PROGRAM DUMP
7 NC
6 MIRROR HEATED
5 HIGH BEAM
Or
4 RH TURN
GOr
3 LH TURN
2 BATT. 24V
ILL & HEAD LAMP 1 IG 24V
SW : ON(1st step) CN-56
GOr
RW
Or
CS-11
8
7
6
5
4
3
2
1
WOr

GOr
RW
RW
YOr
YOr

4BWG
Or

W
R

B
R
B

6
CL-7

CS-23

CS-41
7

3
1

3
1
8

4
9

9
10

10
12

12
11

11
1
2

Hi
C

1 8 7 11 1 8 7 11
Hi Lo

BEACON
B+
C

LAMP
F
L
R
O
L
R

12 10 4 9 3 12 12 10 4 9 3 12
Y 7 Lo

BEACON LAMP SWITCH HAZARD SWITCH

B 5
WB 8
BG 3

BW 2

MULTI FUNCTION SWITCH

7309S7EL10

7-20
GROUP 3 MONITORING SYSTEM
1. CLUSTER
1) STRUCTURE
The cluster consists of gauges, lamps and LCD as shown below, to warn the operator in case of
abnormal machine operation or conditions for the appropriate operation and inspection.
· Gauges : Indicate operating status of the machine.
· Warning lamps : Indicate abnormality of the machine.
· Pilot lamps : Indicate operating status of the machine.
· LCD : Indicates selected the driving speed and direction.
※ The cluster installed on this machine does not entirely guarantee the condition of the
machine. Daily inspection should be performed according to chapter 6, M MAINTENANCE.
AINTENANCE.
※ When the cluster provides a warning immediately check the problem, and perform the
required action.

Speedometer Emergency warning lamp

Left turning pilot lamp Right turning pilot lamp
T/M oil temperature gauge Hyd oil temp gauge
Engine coolant temperature gauge Fuel gauge

Lamps (See page 7-23) Lamps (See page 7-23)

LCD (See page 7-28) Battery volt meter

7579S7EL20

2) GAUGE
(1) Speedometer
Unit ① The speedometer displays the speed of machine in mph and
km/h.
※ The unit ((km/h
km/h or mph
mph)) can be set by the display set up menu
of the monitor and selected unit is displayed.
Refer to page 7-40.
75793CD03

7-21
(2) Fuel gauge
① This gauge indicates the amount of fuel in the fuel tank.
② Fill the fuel when the indicator moves red range or lamp blinks
in red, refuel as soon as possible to avoid running out of fuel.
※ If the gauge indicates below red range even though the
machine is on the normal condition, check the electric device
Red
75793CD04 as that can be caused by the poor connection of electricity or
sensor.

(3) Engine coolant temperature gauge

Red ① This gauge indicates the temperature of coolant.
·White range : 40~104˚C (104~219˚F)
·Red range : Above 104˚C (219˚F)
White ② If the indicator is in the red range or lamp blinks in red, turn
OFF the engine and check the radiator and engine.
75793CD05

(4) Transmission oil temperature gauge

Red ① This gauge indicates the temperature of transmission oil.
·White range : 40~107˚C (104~225˚F)
·Red range : Above 107˚C (225˚F)
White ② If the indicator is in the red range or lamp blinks in red, it
means the transmission is overheated. Be careful that the indi-
cator does not move into the red range.
75793CD06

(5) Hyd oil temperature gauge

Red ① This gauge indicates the temperature of hydraulic oil.
·White range : 40~105˚C (104~221˚F)
·Red range : Above 105˚C (221˚F)
White ② If the indicator is in the red range or lamp blinks in red, reduce
the load on the system.
③ If the gauge stays in the red range, stop the machine and check
75793CD08
the cause of the problem.

(6) Battery volt meter

① This gauge indicates the voltage in the charging system when
the engine is running.
24V 30V
② If the indicator is below 24V, it means that the electricity is being
20V 36V discharged. If the indicator is above 30V, an unusually high volt-
age may damage the alternator. Check the charging system in
both cases.
75793CD07

7-22
3) WARNING LAMPS

Emergency warning lamp Hydraulic oil temperature

T/M oil temperature warning lamp warning lamp
Engine overheat warning lamp Fuel level warning lamp

T/M error warning lamp

Air cleaner warning lamp Battery charging warning lamp
Engine oil pressure warning lamp Steering warning lamp(Emergency)
Steering warning lamp(Primary) Brake fail warning lamp
7609S3CD09

(1) Emergency warning lamp

① This warning lamp blinks and the buzzer sounds when commu-
nication error occur between monitor and MCU.
② When this warning lamp blinks, machine must be checked and
service immediately.

75793CD95

(2) Engine overheat warning lamp

① This lamp is turned ON when the temperature of coolant is over
the normal temperature (106˚C, 223˚F).
② Check the cooling system when the lamp is ON.

77073CD17

(3) Transmission oil temperature warning lamp

① This lamp informs the operator that transmission oil is above the
specified temperature.
② When this lamp lights up during operation, stop the engine and
check the machine.

75793CD35

7-23
(4) Hydraulic oil temperature warning lamp
① This warning lamp operates and the buzzer sounds when the
temperature of hydraulic oil is over 105˚C (221˚F).
② Check the hydraulic oil level when the lamp is turned ON.
③ Check for debris between oil cooler and radiator.

77073CD21

(5) Fuel level warning lamp

① This warning lamp lights ON when the fuel level is low.
Refuel the machine as soon as possible.

77073CD23

(6) Transmission error warning lamp

① This lamp lights ON and the LCD display show the error codes
when an error occurs in the transmission.
② Immediately pull the machine to a convenient stop. Stop the
engine. Investigate the cause.
※ Consult a HYUNDAI dealer to investigate the cause.
77073CD19
※ Do not operate until the cause has been corrected.

(7) Air cleaner warning lamp

① This lamp lights ON when the filter of air cleaner is clogged.
② Check the filter and clean or replace it when the lamp is ON.

77073CD20

(8) Engine oil pressure warning lamp

① This lamp is comes ON after starting the engine because of the
low engine oil pressure.
② If the lamp comes ON during engine operation, shut OFF engine
immediately. Check engine oil level.

77073CD18

7-24
(9) Steering warning lamp
① Primary
This lamp indicates that the primary steering has failed. When
the indicator comes on and the action alarm sounds, steer the
machine immediately to a convenient location and stop the
machine. Stop the engine and investigate the cause.
※ Do not operate the machine until the cause has been cor-
77073CD66
rected.

② Emergency
This lamp indicates the emergency steering system is active.
※ Immediately pull the machine to a convenient stop and stop
the engine.
※ The emergency steering system can be manually tested.
77073CD15
Refer to page 7-45.

(10) Battery charging warning lamp

① This lamp is ON when key ON, it is turned OFF after starting the
engine.
② Check the battery charging circuit when this lamp comes ON,
during engine operation.

77073CD22

(11) Brake fail warning lamp

① The lamp lights ON when the oil pressure of service brake drops
below the normal range.
② When the lamp is ON, stop the engine and check for its cause.
※ Do not operate until any problems are corrected.

77073CD16

7-25
4) PILOT LAMPS

Warming up pilot lamp Seat belt pilot lamp

Mirror defrost pilot lamp Fuel warmer pilot lamp
Preheater pilot lamp High beam pilot lamp

Parking brake pilot lamp

Fan reverse pilot lamp

Maintenance pilot lamp Clutch cut off pilot lamp

Ride control pilot lamp(Auto)
Ride control pilot lamp(On)

7609S3CD10

(1) Warming up pilot lamp

① This lamp is turned ON when the coolant temperature is below
30˚C (86˚F).
② The automatic warming up is cancelled when the engine coolant
temperature is above 30˚C, or when 10 minutes have passed
since starting the engine.
75793CD31

(2) Seat belt pilot lamp

① This lamp lights ON for the first five seconds after starting the
engine.

75793CD17

(3) Mirror defrost pilot lamp

① This lamp comes ON when mirror defrost switch is pressed.
※ Refer to page 7-44 for details.

7807A3CD11

7-26
(4) High beam pilot lamp
① This lamp works when the illuminating direction is upward.
② This lamp comes ON when the dimmer switch is operated, e.g.,
when passing another vehicle.

77073CD12

(5) Preheat pilot lamp

① This lamp lights ON when start switch is turned clockwise to the
ON position. Light will turn off after approximately 5~45 sec-
onds, depending on engine temperature, indicating that preheat-
ing is completed.
② When the lamp goes out the operator should start cranking the
77073CD14 engine.

(6) Parking brake pilot lamp

① When the parking brake is actuated, the lamp lights ON.
※ Check the lamp is OFF before driving.

77073CD13

(7) Maintenance pilot lamp

① This lamp will be ON when the consuming parts are needed
to change or replace. It means that the change or replace-
ment interval of the consuming parts remains below 30
hours.
② Check the message in maintenance information of the moni-
tor menu. Also, this lamp lights ON for 3 minutes when the
75793CD32
start switch is ON position.

(8) Clutch cut off pilot lamp

① This lamp lights ON when the clutch cut off mode switch is
positioned L, M, H.
※ Refer to page 7-45.

77073CD65

7-27
(9) Ride control pilot lamp (option)
① Auto ride control
This lamp lights ON when push in the bottom of the ride control
switch (auto position).
※ Refer to page 7-44.

75793CD33

② Manual ride control

This lamp lights ON when push in the top of the ride control
switch (manual position)
※ Refer to page 7-44.

75793CD34

(10) Fan reverse pilot lamp

① This lamp lights ON when the fan control switch is pressed.
※ Refer to page 7-44.

7707A3CD40

(11) Fuel warmer pilot lamp

① This lamp is turned ON when the coolant temperature is below
10˚C (50˚F ) or the hydraulic oil temperature 20˚C (68˚F ).
② The automatic fuel warming is cancelled when the engine
coolant temperature is above 60˚C and the hydraulic oil tem-
perature is above 45˚C since the start switch was ON position.
21093CD43

5) LCD
Type 1 (1) The LCD can be used with the gear selector.
It indicates speed and driving direction.
2
3 No Symbol Meaning Remark
2
Forward, reverse, neutral
1 1 1, 2, 3, 4 Actual gear display Actual gear
75793CD39
P Parking brake mode active

2 , Forward, reverse Automatic mode

3 Gear range display Automatic mode

7-28
2. MONITOR

·The monitor is adjustable.

- Vertical : 14˚
- Horizontal : 30˚

Vertical

Main display
Horizonta
l

Menu button Enter button

Left move button Right move /

buzzer stop button
Camera / ESC button
75793CD23

1) BUTTONS
(1) Menu button
① Main display to main menu, main menu to main display.
② AEB cancel button in AEB setting.

75793CD90

(2) Left move button

① Move in menu (left, up).

75793CD91

(3) Camera / ESC button

① Enter rear camera mode in main display.
② Cancel button except in main display (move previous menu).

75793CD92

(4) Right move / Buzzer stop button

① Move in menu (right, down).
② Buzzer stop.

75793CD93

(5) Enter button

① Select menu (enter).
② AEB cancel button in AEB setting.

75793CD94

7-29
 2) MAIN MENU
Main display
1 3
6
7
4 Main menu

5
8
10 Press
9
TYPE A (default)

2 8
9
5
10

6
7
TYPE B 75793CD11

1 Buzzer 5 Select gear 9 Hour meter, odometer

2 Clock 6 Engine mode 10 Monitoring
3 Wiper speed 7 Transmission mode
4 Actual gear 8 Engine rpm
※ Display type can be changed by operator. See page 7-40.

(1) Structure
No Main menu Sub menu Description
Engine speed Engine warming up, Engine speed
Kick down Mode 1 (down/up), Mode 2 (down only)
Wiper speed 4 steps
1
Fan-auto mode Interval and time setting
MODE AEB AEB setting
75793CD12
Speed meter Pulse setting
Fault code Active, logged fault (machine, ECU, TCU)
Machine monitoring Hyd temp, Battery, Coolant temp
T/M oil temp
2
Monitoring history Hour meter, ODO meter
MONITORING
75793CD13

Machine security ESL system setting, Change password

Maintenance Replacement, Change interval (oils and filters)
Machine information Version, Status
3
Service contact Service contact
MANAGEMENT Service menu S/W download
75793CD14

Clock Clock
Display Brightness setting (Manual/Automatic)
Type display (A or B type)
4
Unit Temp (˚F/˚C), Distance (km/mile), Pressure (bar, Mpa, kgf/m2, psi)
DISPLAY SET UP Rear camera Reverse mode, Active camera, Display order
75793CD13
Language 12 languages

7-30
(2) Mode
① Engine speed

75793CD16

75793CD16A 75793CD16B

Set low idling speed

75793CD16C 75793CD16D

② Kick down

75793CD17

75793CD17A

· Mode 1 (down/up) : Press kick down button once, shift down and press button again, shift up.
· Mode 2 (down only) : Press kick down button every time, shift to lower gear respectively.
※ Refer to page 7-46.
③ Wiper speed

75793CD18
· Setting wipe speed 1 to 4.
75793CD18A

④ Fan-auto mode

75793CD110

75793CD111 75793CD112

· Select reverse interval or reverse time.

· Set reverse interval (30~300 min) or reverse time (30~300 sec).
※ Default : Interval (60 min), time (120 sec)
※ Refer to page 7-44, fan control switch.

7-31
⑤ AEB
Actual gear window

75793CD19

75793CD19A

· AEB mode controls the disk clearance of the transmission, automatically.

· To start AEB setting, press and hold for 3 seconds.
· To cancel AEB setting, press , or .
· If "OK" in actual gear window, press , or to complete AEB setting.
· Display during AEB mode
Symbol Meaning
ST Start AEB
K1~K4, KV, KR Calibrating clutch K1~K4, KV or KR respectively
OK* Calibration for all clutches finished

Spanner and Kx* Kx couldn't be calibrated, AEB finished

Engine speed too low
△E
- Raise engine speed
Engine speed too high
▽E
- Lower engine speed
Transmission oil temperature too low
△T
- Heat up transmission
Transmission oil temperature too high
▽T
- Cool down transmission
FO* Output speed not zero

FN* Shift lever not in neutral position

FP* Parking brake not applied

* : Transmission stays in neutral, you have to restart the TCU (ignition off/on).

⑥ Speed meter

75793CD20

75793CD20B 75793CD20A

· Press and hold for 3 seconds.

· To change the pulse value, press or .
· To change the position, press .
※ Only for the serviceperson.

7-32
(3) Monitoring
① Fault code

75793CD23

75793CD23C 7709S3CD23D

75793CD23E 7709S3CD23

7709S3CD23G

75793CD23H 75793CD23I

75793CD23J

· Monitor the fault code of the Machine / ECU / TCU .

※ Not define will be indicated in case of that there's no fault.

7-33
② Machine monitoring

75793CD24

7709S3CD24A 7709S3CD24B

· Monitor the status of the machine.

· To check the item in main display, choose it and press .
· The right icon shows ON / OFF status.

③ Record monitoring

75793CD25

75793CD25A 75793CD25C

· Hour meter
- Total : total hour meter
To show the item in the main display, select "ON"
and press (this item could not reset).
- Latest : the latest hour meter after reset.
To show the item in the main display, select "ON"
and press . 75793CD25D

To reset the latest hour meter, select "initializing" and

press .

75793CD25F 75793CD25H

· ODO meter
- Total : total ODO meter
To show the item in the main display, select "ON"
and press (this item could not reset).
- Latest : the latest ODO meter after reset.
To show the item in the main display, select "ON"
and press .
75793CD25J
To reset the latest odometer, select "initializing" and
press .

7-34
 (4) Management
① Machine security

75793CD26

75793CD26A 75793CD26B

· ESL system setting

- ESL : Engine Starting Limit
- ESL mode is designed to be a theft deterrent or will pre-
vent the unauthorized operation of the machine.
- If the ESL mode was selected Enable, the password will
be required when the start switch is turned ON.
- Disable : Not used ESL function
Enable : The password is required whenever the 75793CD26C

operator start engine.

Interval mode : The password is required when the opera-
tor start engine first. But the operator can
restart the engine within the interval time
without inputting the password.
The interval time can be set maximum 2
days.
※ Default password : 00000
* 75793CD26D

· Interval setting
- If set interval setting to 5 minutes,
ESL system is activated after 5
minutes.
Therefore, the password does not
need to restart engine within 5
minutes. 75793CD26J 75793CD26K

7-35
· Change password
- Input 5 to 10 digits and press *.

75793CD26G 75793CD26H
Enter the current password.

75793CD26L
Enter the new password.

75793CD26N 75793CD26M
The new password is stored Enter the new password
in the MCU. again.

7-36
② Maintenance

75793CD27

75793CD27A 75793CD27B

75793CD27D 75793CD27C

· Alarm ( ) : Warning
Replacement : The elapsed time will be reset to zero.
Change cycle : The change or replace cycle can be changed in the unit of 50 hours.
· To change cycle, press or .
· Change or replace interval
No Item Interval
1 Engine oil 500
★1
2000
2 Hydraulic oil ★2
5000
3 Pilot line filter element 250
4 Hydraulic oil return filter 250
5 Engine oil filter 500
6 Fuel filter element 500
7 Fuel pre-filter 500
8 Hydraulic tank air breather 250
9 Radiator coolant 2000
10 Transmission oil and filter 1000
11 Axle oil (front and rear) 1500
★1
: Conventional hydraulic oil
★2
: Hyundai genuine long life hydraulic oil

7-37
③ Machine information

75793CD28 HL730-9S

75793CD28A 7309S3CD28B

75793CD28C 75793CD28D

· Version
- Software versions of MCU, cluster and monitor can be
checked.
· Status info
- The machine status can be checked.

75793CD28E

④ Service contact

75793CD29

75793CD29A 75793CD29B

· The phone number of the service man can be checked and changed.

⑤ Service menu

75793CD30

75793CD30A 75793CD30B

· The software of monitor can be downloaded.

7-38
(5) DISPLAY SET UP
① Clock

75793CD32

75793CD32A

· To set time, press or .

· To move position, press .

② Display
· Brightness setting

75793CD33

75793CD33A

75793CD33B 75793CD33C
Manual (1st~8th step)

75793CD33D 75793CD33E

Auto (day / night)

※ If "Automatic" is chosen, brightness for day and night can be differently set up. Also by
using the bar in lower side, users can define which time interval belongs to day and night.
(in bar figure, gray area represents night time while white shows day time)

7-39
 · Display type

75793CD33F 75793CD33G 75793CD33H

A type

75793CD33I
B type

③ Unit

75793CD34

75793CD34A 75793CD34B

· Temperature : ˚C ↔ ˚F
· Distance : km ↔ mile
· Pressure : bar ↔ Mpa ↔ kgf/m2 ↔ psi

7-40
④ Rear camera

75793CD35

75793CD35A 75793CD35B

75793CD35C 75793CD35D

75793CD35E 75793CD35F

· Reverse mode
- If transmission engages the reverse gear (R1~R3), the camera mode is displayed
automatically in main display.
· Active camera
- Three cameras can be installed on the machine.
- The display order can be set by this menu.
· If the camera was not equipped, this menu is not useful.
· In main display, if the button is pushed, the first ordered display camera will be viewed.

⑤ Language

75793CD36

75793CD36A 75793CD36B

· User can select preferable language and all display are changed the selected language.

7-41
3. SWITCHES

Cab ceiling LH side

Mirror defrost switch(option) A

M
Rear wiper/washer switch
Beacon switch(option) M

USB socket
Fan control switch
Emergency test switch(opt)

Main light switch

Work lamp switch
Hazard switch
Kick down switch
T/M shift mode switch Parking brake switch
Clutch cut off mode switch Ride control switch(opt)
Multi function switch

P
Horn button
Starting switch
Engine mode switch

7309S3CD29

1) STARTING SWITCH
(1) There are three positions, OFF, ON and START.
· (OFF) : None of electrical circuits activate.
· (ON) : All the systems of machine operate.
· (START) : Use when starting the engine.
Release key immediately after starting.
※ If you turn ON the starting switch in cold weather, the fuel warm-
77073CD41
er is automatically operated to heat the fuel by sensing the cool-
ant temperature. Start the engine in 1~2 minutes after turning
ON the starting switch. More time may take according to ambi-
ent temperature.
※ Key must be in the ON position with engine running maintain
electrical and hydraulic function and prevent serious machine
damage.

7-42
2) HAZARD SWITCH
(1) Use for parking, or loading the machine.
ON
OFF (2) Both turn signal lights will flash simultaneously.
※ If the switch is left ON for a long time, the battery may be dis-
charged.

75793CD42

3) PARKING BRAKE SWITCH

Safety button (1) When the switch is pressed to ON position, the parking brake will
ON start to operate and the cluster warning lamp will comes ON.
Release
Lock
(2) Press the release position in order to disengage the parking brake.
Unlock
※ When operating the gear selector lever, be sure to release the
P

parking brake. If the machine is operated with the parking brake

75793CD44 engaged, the brake will overheat and may cause the brake sys-
tem to go out of order.
※ This switch can be set to ON or Release position only when the
safety button is pulled to the unlock position.

4) MAIN LIGHT SWITCH

(1) This switch use to operates the clearance lamp and head light by
two step.
·First
First step : Clearance lamp and cluster illumination lamp
comes ON. Also, all indicator lamp of switches
come ON.
·Second
Second step : Head light comes ON.
75793CD45

5) WORK LAMP SWITCH

(1) This switch use to operates the front and rear work lamps by two
step.
·First
First step : Front work lamp located on the cab comes ON.
·Second
Second step : Rear work lamp located on the cowl comes ON.

75793CD46

6) REAR WIPER AND WASHER SWITCH

(1) The switch use to operates the rear wiper and washer by two step.
OFF ·First
First step : The rear wiper operates.
ON
·Second
Second step : The washer liquid is sprayed and the rear wiper is
operated only while pressing. If release the switch,
return to the first step position.
75793CD47

7-43
7) FAN CONTROL SWITCH
(1) This switch use to control the cooling fan.
OFF
AUTO (2) This switch has three positions.
MANUAL ·AUTO
UTO : The fan automatically work in reverse according to set
up interval and time.
※ Refer to page 7-31.
·OFF
OFF : Only forward rotation is possible.
75793CD49
·MANUAL
MANUAL : The fan rotates reverse only while pressing this position.
If release the switch, return to the OFF position.
(3) On pressing the switch, the indicator lamp is turned ON.

8) MIRROR DEFROST SWITCH (option)

(1) If the mirror defrost switch is pressed in condition of key ON, it oper-
ates for 15 minutes. After 15 minutes, the defrost function stops
automatically.
(2) One more pressing the switch in operation also stops defrost func-
tion.
(3) On pressing the switch, the indicator lamp is turned ON.
75793CD48

9) BEACON SWITCH (option)

(1) This switch turns ON the rotary light on the cab.

75793CD50

10) RIDE CONTROL SWITCH (option)

OFF (1) AUTO
MANUAL Press in the bottom of the ride control switch in order to turn on the
AUTO automatic ride control. The automatic ride control automatically
turns on when the travel speed exceeds a preset speed of approxi-
mately 7 km/h. The automatic ride control automatically shuts off dur-
75793CD51 ing low speed travel (below 7 km/h).
(2) MANUAL
(2
Press in the top of the ride control switch in order to turn on the sys-
tem for ride control regardless speed. The ride control will smooth
the ride of the machine during travel.
(3) OFF
(3
Press the ride control switch to the middle position in order to turn
off the system for the ride control.

7-44
11) EMERGENCY TEST SWITCH (option)
(1) The emergency steering system can be manually tested. Push the
switch in order to determine if the emergency steering and the
emergency steering lamp are functional.
M

(2) When the switch is pressed, the emergency steering pump motor
will run. The emergency steering lamp will light. If the emergency
75793CD52
steering lamp does not light, do not operate the machine.

12) ENGINE MODE SWITCH

(1) The operator can adjust the machine's performance with this dial
S switch.
E P
· P (Power) : Maximum power output for hard digging operation
or hill climb.
· S (Standard) : General digging and loading operation.
· E (Econo) : Maximum fuel efficiency for general loading.
75793CD57

13) CLUTCH CUT OFF MODE SWITCH

(1) Four modes are available for operator's preference and job condition.
L M · OFF : The clutch cut off function is disable.
OFF H · L (Low) : The clutch is disengaged early for short-distance
and rapid loading.
· M (Medium) : The clutch is disengaged normally for general dig-
ging and loading operation.
· H (High) : The clutch is disengaged lately for slope ground.
M mode (2) The clutch cut off functions of the left brake pedal depend on the
L mode
position of the left brake pedal and the position of the clutch cut off
mode switch.

H mode Positions for clutch cut off function

Left brake pedal

Clutch cut off mode switch L M H
75793CD58 Left brake pedal L, M, H M, H H

14) TRANSMISSION SHIFT MODE SWITCH

(1) Four modes are available for operator's preference and job
A
.
. AN
AL
.
condition.
MAN AH
· MAN (Manual) : Machine is operated by selected gear on
lever.
· AL (Auto Light) : Automatic shifting point is fast for long-dis-
tance transportation and fuel efficiency.
75793CD59
· AN (Auto Normal) : Automatic shifting point is normal without
automatic kick-down to 1st gear for general
digging and loading operation.
· AH (Auto Heavy) : Automatic shifting point is normal with auto-
matic kick-down to 1st gear for more power-
ful operation.

7-45
15) HORN BUTTON
Horn button (1) If you press the button on the top of the multifunction switch, the
horn will sound.

7609S3CD16

16) CAB LAMP SWITCH

(1) This switch turns ON the cab room lamp.
DOOR ON ① DOOR
The lamp comes ON when the door is opened.
When the door is closed the lamp is OFF.
② ON
This switch is used to turn the lamp ON or OFF.
75793CD63

17) USB SOCKET

(1) MP3 files are played when a USB device is connected to the USB
port.
(2) In addition, the AUX port enables headphone and other devices.
AUX USB

HB1003CD63

18) KICK DOWN SWITCH

Kick down switch (1) Manual mode
It is effective 2nd speed to 1st speed only and recover to 2nd speed
quickly when push the switch one more time.
(2) Automatic mode
① Mode 1 (down/up)
It shifts down quickly from current gear to one step lower speed by
pushing the switch and recover to current speed quickly when push
7609S3CD24
the switch one more time.
② Mode 2 (down)
It shifts down from current gear to one step lower speed when
push the switch every time.
The kick down function is released in only 1st speed.
※ Refer to page 7-31 for the kick down setting.
※ The normal autoshift function continues after the kick down
switch is released.

7-46
19) MULTI FUNCTION SWITCH
O J ⅠⅡ (1) Front wiper and washer switch
① When the switch is in J position, the wiper moves intermittently.
② When placed in Ⅰ or Ⅱ position, the wiper moves continuously.
③ If you push the grip of the lever, washer liquid will be sprayed and
the wiper will be activated 2-3 times.
73033CD29
※ Check the quantity of washer liquid in the tank. If the level of
the washer liquid is LOW, add the washer liquid (in cold, winter
days) or water. The capacity of the tank is 1 liter.

Up (2) Dimmer switch

① This switch is used to turn the head lights direction.
M
② Switch positions
Down ·Up : To flash for passing
·Middle : Head lights low beam ON
73033CD30 ·Down : Head lights high beam ON
③ If you release the switch when it's in up position, the switch will
return to middle.

Left turning (3) Turning switch

① This switch is used to warn or signal the turning direction of the
machine to other vehicles or equipment.
② Push the lever up for turning left, pull the lever down for turning
Right turning right.
73033CD31

7-47
GROUP 4 ELECTRICAL COMPONENT SPECIFICATION

Part name Symbol Specifications Check item

Gravity
12V × 100Ah 1.280 over : over charged
Battery
(2EA) 1.280 ~ 1.250 : normal
1.250 below : discharged

Rated load : 24V Coil resistance

Battery relay 100A (continuity) breaked : approx 50Ω
1000A (30seconds) connected :∞Ω

CR-1

Resistance between ring termi-

Fusible link 24V nal and each connector pin
0Ω: normal
CN-60 (40A)
CN-95 (80A)

H BR ACC ST C
23 56
H 0 I II 4
Resistance between each pin
B-BR : 24V 1A
Key off : ∞Ω(for each pin)
Start key 0, I 1
B-ACC : 24V 10A
B Key on : 0Ω(for pin 1-2 & 1-3)
B-ST : 20V 40A
1 2 3 4 5 6 Start : 0Ω(for pin 1-5)

CS-2

A
- S +

Pa
Voltage
B
Pressure sensor C
- Pin A, B : 24V
Pin B, C : 1~5V
CD-3 CD-26 CD-39 CD-40

T/M filter 1 Resistance

N.O Type
pressure sensor 2 Pa ∞Ω: normal (open)

CD-48

7-48
 Part name Symbol Specifications Check item

1
Parking brake Resistance
2 24V 1A
solenoid normal : 15~25Ω
CN-71

Air cleaner Pa Max load : 6W Resistance

pressure switch N.O Type ∞Ω: normal (open)
CD-10

Ride control 2 ※ Check LED lamp

valve / Fan sole- 1 24V 1.2A ※ Check resistance
noid about 24Ω
CN-136 CN-154 CN-155

Resistance at fuel levels

full level : 200Ω
1 9/12 level : 500Ω
Fuel sender -
2 6/12 level : 800Ω
3/12 level : 1100Ω
CD-2
empty : 1300Ω

1 2 1
Resistance at normal position
Relay 2
3 24V 20A about 200Ωbetween pin 1-3
(4pin)
4 4 3 ∞Ω between pin 2-4
AC RY(H1)
CR-2 CR-26 AC RY1
CR-5 CR-30 AC RY2

30
87a 87 85
86 Resistance
87
normal : about 160Ω
Relay 85
87a 30 86 24V 20A (for pin 85~86)
(5pin)
0Ω(for pin 30~87)
CR-5 CR-37 CR-46
CR-25 CR-40 CR-59 ∞Ω(for pin 30~87)
CR-35 CR-41 CR-60

7-49
 Part name Symbol Specifications Check item

2 3 4
1
Resistance
5 normal : about 160Ω
Relay 2
1 5 4 24V 20A (for pin 1~2)
(5 pin) 3
0Ω(for pin 3~4)
CR-2 CR-4 CR-26 CR-38 CR-58
CR-3 CR-7 CR-36 CR-55 CR-63 ∞Ω(for pin 3~5)

2 Resistance
Hydraulic C
- normal : ∞Ω
temperature 1
105。C over : 0Ω
CD-1

1 Resistance
Speaker 4Ω 20W
2 normal : 4Ω

CN-23(LH)
CN-24(RH)
7

3
1
10

4
12

9
11

1 8 7 11 Resistance at switch off position

Switch ∞Ωbetween pin 1-5 and 2-6
24V 8A
(Locking type) 12 10 4 9 3 12 0Ωbetween pin 5-7 and 6-8
CS-17 CS-41
CS-23 CS-76
12
12

Resistance at switch off position

3
4

Switch
∞Ωbetween pin 1-5 and 2-6
(Non-locking 24V 8A
1
11

9
7

0Ωbetween pin 5-7 and 6-8

11
12

type)
9
4

6
1
3

CS-21 CS-36

Work lamp
1
Work lamp, 24V 65W
2
Room lamp, Number plate lamp Resistance
Numbaer plate CL-1
CL-1 CL-21CL-6
CL-32 CL-22
CL-35 24V 10W normal : 1.2Ω
lamp CL-5 CL-22 CL-33 CL-23
CL-5 CL-21 CL-36 Room lamp
CL-6 CL-23
24V 10W

7-50
 Part name Symbol Specifications Check item

M 24V 70W Resistance

Beacon lamp
(H1 TYPE) normal : 1.1Ω
CL-7

2 24V
24V Resistance
DC/DC 1 GND 12V 3A 8.8Ω(for pin A-B)
Converter 3 12V
12V
7.7Ω(for pin B-C)
CN-138

Operation by external power

source
Horn 24V 2A - conncet 24V power to (+)
CN-20 CN-25 terminal
- ground the (-) terminal

2 Resistance
PA
Receiver dryer 24V 2.5A 0Ω: 2.1±0.3~27±2kgf/cm²
1
∞Ω: ~2.1±0.3, 27±2~kgf/cm²
CN-29
REMOCON GND
SPK FRT RH+

SPK FRT LH+

SPK FRT RH-
SPK FRT LH-

REMOCON+

Resistance
BACK UP+
TEL MUTE
ANT 12V

Radio & USB

24V 20W+20W Power ON : 4Ω+4Ω
GND

GND
ACC

ILL+
ILL-

NC

NC

player
(for pin 1-6, 4-8)
10
11
12
13
14
15
16
8
1
2
3
4
5
6
7

CN-27

24V 0.5A Resistance

Back up buzzer
110dB normal : 5.2Ω
CN-65

7-51
 Part name Symbol Specifications Check item

M 1 Resistance
Washer pump 2 24V 2.5A normal : 26.4 Ω
(for pin1-2)
CN-103
CN-22 (FR)CN-22
CN-103 (RR)

E 3 1
Pf 2 2
B 1 3
4 24V 1.5A
Hi 4 5
Wiper motor Lo 5 6
2-speed -
M
Auto parking
CN-21 (FR) CN-102 (RR)

B
A Coil resistance
Cigar lighter 24V 5A 1.4W
1 normal : about 1MΩ

CL-2

B+
G
1 P
3~
2 L
U
Voltage
Alternator 3 FI 24V 70A
4 NC normal : 24~28V
CN-74

M
Nippondenso
Starter Operating or not
24V-3.7kW
B+ M
CN-45

1 Resistance
Aircon
24V 79W
compressor normal : 13.4Ω
CN-28

7-52
Part name Symbol Specifications Check item

Coil resistance
normal : 1-2Ω
Start relay 24V 300A Switch connection
∞Ωat normal open position
CR-23 0Ωwhen engaged

M Resistance at each switch posi-

1
Blower 24V 9.5A tion
2 normal : 0.5-2Ω

Resistance
Door switch 24V 2W
normal : about 5MΩ

CS-1 CS-55

3 E
G 24V
2 B
Flasher unit 1 L
85 ~ 190 C/M -
50dB
CR-11

6 Lo
4 Hi 24V 75W/70W
5 (H4 TYPE) Resistance
Head lamp 3 C
E
24V 4W normal : a fewΩ
2
ABL

1 T (T4W)
CL-3 CL-4

4 C
24V 5W
3 T
Combi lamp (R5W)
2 E -
(rear) 2×24V 21W
1 S
(P21W)
CL-15 CL-16

7-53
 Part name Symbol Specifications Check item

Continuous capaci-
ty :
Master switch 180Amp -
Push in capacity :
CS-74 1000Amp

2
24V 200mA
Warning buzzer 1 -
90±5dB (ℓm)
CN-26

Resistance
Preheater 24V 200A
0.25~0.12Ω
CN-80

A A

B Resistance
Resistor 4W
C B A - B : 120Ω
CN-99

7-54
GROUP 5 CONNECTORS

1. CONNECTOR DESTINATION
Connector No. of Connector part No.
Type Destination
number pin Female Male
CN-5 DEUTSCH 48 I/conn (Frame harness-Main harness) DRB16-48SAE-L018 DRB12-48PAE-L018
CN-6 DEUTSCH 60 I/conn (Frame harness-Main harness) DRB16-60SBE-L018 DRB12-60PBE-L018
CN-7 AMP 15 I/conn (Main harness-Cab harness) 2-85262-1 368301-1
CN-9 AMP 12 I/conn (Cab harness-Main harness) 2-85262-1 368301-1
CN-10 DEUTSCH 24 I/conn (Front harness-Frame harness) HD34-24-23PE HD36-24-23SE
CN-11 DEUTSCH 8 I/conn (Main harness-Aircon harness) DT06-8S DT04-8P
CN-12 AMP 15 I/conn (Frame harness-Bottom harness) 2-85262-1 368537-1
CN-13 DEUTSCH 12 I/conn (Frame harness-Engine harness) DT06-12S DT04-12P
CN-14 DEUTSCH 12 I/conn (Frame harness-Grill harness) DT06-12S DT04-12P
CN-19 Econoseal J 6 I/conn (Emer steer harness-Frame harness) S816-006002 S816-106602
CN-20 MOLEX 2 Horn 36825-0211 -
CN-21 AMP 6 Front wiper motor 936257-1 -
CN-22 KET 2 Front washer tank MG640605 -
CN-23 KET 2 Speaker (LH) 7123-1520 -
CN-24 KET 2 Speaker (RH) 7123-1520 -
CN-25 MOLEX 2 Horn 36825-0211 -
CN-26 250 2 Warning buzzer S810-002202 -
CN-27 MK II 16 Radio and USB player PK145-16017 -
CN-27A MK II 8 USB connector 174984-2 -
CN-28 NMWP 1 Aircon compressor PB625-01027 -
CN-29 KET 2 Receiver drier MG640795 -
CN-36 - - Fuse box 21Q7-10910 -
CN-45 Ring term - Starter R14-12 ST 710384-2
CN-56 AMP 20 Cluster 174047-2 -
CN-57 AMP 20 Monitor 174047-2 -
CN-58A DEUTSCH 40 MCU DRC26-40-SA -
CN-58B DEUTSCH 40 MCU DRC26-40-SB -
CN-60 MTA 2 Fusible link (40A) 07.00910 03.21000
CN-65 DEUTSCH 2 Back up buzzer DT06-2S -
CN-71 DEUTSCH 2 Parking solenoid DT06-2S-EP06 -
CN-74 PACKARD 4 Alternator 1218-6568 -
CN-80 Ring term - Preheater R14-6 -
CN-83 NMWP 2 Aircon fan PB625-02027 -

7-55
Connector No. of Connector part No.
Type Destination
number pin Female Male
CN-93 DEUTSCH 50 ECM DRC26-50S-04 -
CN-94 DEUTSCH 4 ECM power DTP06-4S-EP06 -
CN-95 MTA 2 Fusible link (80A) 07.00960 03.21000
CN-96 PACKARD 2 Fuel heater 2-967325-3 -
CN-99 DEUTSCH 2 Resister DT04-3P-EP10 -
CN-100 Econoseal J 3 Boom kick out S816-003002 S816-103002
CN-101 Econoseal J 3 Bucket leveler S816-003002 S816-103002
CN-102 AMP 6 Rear wiper motor 936257-1 -
CN-103 KET 2 Rear washer tank MG640605 -
CN-110 DEUTSCH 2 Joystick DT06-2S -
CN-112 - 16 Gear box 21L7-60290 -
CN-114 DEUTSCH 6 Joystick DT06-6S -
CN-126 DEUTSCH 9 Data link HD10-9-96P -
CN-136 AMP 2 Ride control solenoid 85202-1 -
CN-138 250 3 DC/DC Converter S810-003202 -
CN-139 250 2 12V socket S810-002202 -
CN-140 Econoseal J 3 I/conn (Front harness-Quick coupler harness) S816-003002 S816-103002
CN-141 Econoseal J 6 I/conn (Ride control harness-Front harness) S816-006002 S816-106002
CN-149 DEUTSCH 2 Mirror heat (LH) DT06-2S DT04-2P
CN-150 DEUTSCH 2 Mirror heat (RH) DT06-2S DT04-2P
CN-154 AMP 2 Fan speed solenoid 85202-5 -
CN-155 AMP 2 Fan reverse solenoid 85202-1 -
CN-156 PACKARD 2 Seat heater 1205-2641 1205-2647
CN-157 AMP 60 T/M control unit 962175 -
CN-158 PACKARD 4 Gear shift lever - 1201-0974
CN-159 PACKARD 4 Gear shift lever 1201-5797 -
CN-162 Econoseal J 6 Pedal S816-006002 -
CN-170 250 2 Seat heater S810-002202 -
CN-244 DEUTSCH 3 PTC CAN 2 DT06-3S-E008 DT04-3P-EP10
CN-246 KET 1 PTC power - MG620659-5
CN-250 Econoseal J 4 Rear view camera S816-004002 S816-104002
·Relay
CR-1 Ring term - Battery relay S820-104002 -
CR-2 AMP 5 Horn relay VCFM-1002 -
CR-3 HELLA 5 Front work lamp relay 8JA003526-001 -
CR-4 AMP 5 Wiper relay (Hi) VCFM-1002 -
CR-5 HELLA 5 Safety relay 8JA003526-001 -

7-56
Connector No. of Connector part No.
Type Destination
number pin Female Male
CR-7 HELLA 5 Aircon relay 8JA003526-001 -
CR-11 HELLA 5 Flasher unit 8JA003526-001 -
CR-23 Ring term - Start relay ST 710289-2 ST 710384-2
CR-24 Shur 1 Preheater relay S822-014000 -
CR-25 HELLA 5 ECM power relay 8JA003526-001 -
CR-26 AMP 5 Wiper relay (low) VCFM-1002 -
CR-36 AMP 5 Preheater relay VCFM-1002 -
CR-39 DEUTSCH 2 Emergency steering pump relay DT06-2S DT04-2P
CR-46 HELLA 5 Fuel warmer relay 8JA003526-001 -
CR-55 HELLA 5 Rear work lamp relay 8JA003526-001 -
CR-56 KET 4 Mirror heat relay MG610047-1 -
CR-58 AMP 5 Back up relay VCFM-1002 -
CR-60 AMP 5 Ride control speed relay VCFM-1002 -
CR-63 AMP 5 Stop lamp relay VCFM-1002 -
·Switch
CS-1 Shur 1 Door switch S822-014004 -
CS-2 SWP 6 Start key switch S814-006000 -
CS-5 Shur 1 Horn switch S822-014000 -
CS-11 SWP 8 Multi function switch S814-008000 -
CS-12 SWP 6 Multi function switch S814-006000 -
CS-17 SWF 12 Parking switch 589790 -
CS-21 SWF 12 Main light switch 589790 -
CS-23 SWF 12 Beacon switch 589790 -
CS-35 SWF 12 Rear wiper switch 589790 -
CS-36 SWF 12 Work lamp switch 589790 -
CS-41 SWF 12 Hazard switch 589790 -
CS-42 DEUTSCH 3 Clutch cut off dial switch - DT06-3S-E008
CS-55 SWF 12 Ride control switch 589790 -
CS-59 DEUTSCH 3 Transmission shift dial switch - DT06-3S-E008
CS-73 SWF 12 Fan reverse switch 589790 -
CS-74 Ring term 4 Master switch ST710287-2 S820-205000
CS-75 SWF 12 Emergency steering test switch 589790 -
CS-76 SWF 12 Mirror heater switch 589790 -
CS-80 DEUTSCH 3 Econo mode dial switch DT06-3S-E008 -

7-57
Connector No. of Connector part No.
Type Destination
number pin Female Male
·Light
CL-1 KET 3 Room lamp MG651032 -
CL-2 250 3 Cigar lighter S810-003202 -
CL-3 DEUTSCH 6 Head light (LH) DT06-6S -
CL-4 DEUTSCH 6 Head light (RH) DT06-6S -
CL-5 DEUTSCH 2 Work light (LH) DT06-2S-EP06 -
CL-6 DEUTSCH 2 Work light (RH) DT06-2S-EP06 -
CL-7 250 2 Beacon lamp S810-002202 -
CL-15 SWP 4 Combi lamp (RR, LH) S814-004000 -
CL-16 SWP 4 Combi lamp (RR, RH) S814-004000 -
CL-21 SWP 2 Numberplate lamp S814-002000 -
CL-22 DEUTSCH 2 Work light (LH) DT06-2S -
CL-23 DEUTSCH 2 Work light (RH) DT06-2S -
CL-24 SWP 2 Turn lamp (LH) S814-002000 -
CL-25 SWP 2 Turn lamp (RH) S814-002000 -
CL-30 KET 2 Room lamp MG610392 -
CL-32 DEUTSCH 2 Rear work light (RH) DT06-2S-EP06 DT04-2P-E005
CL-33 DEUTSCH 2 Rear work light (LH) DT06-2S-EP06 DT04-2P-E005
·Sensor, sender
CD-1 AMP 2 Hyduaulic oil temp sendor 85202-1 -
CD-2 SWP 2 Fuel sendor S814-002000 -
CD-3 DEUTSCH 3 Brake fail pressure switch DT06-3S -
CD-4 DEUTSCH 4 Stop lamp / clutch cut off pressure switch DT06-4S-EP06 -
CD-10 Ring term 2 Air cleaner switch GP890469 -
CD-17 AMP 2 Engine pick-up sensor 85202-1 -
CD-26 DEUTSCH 3 Parking pressure switch DT06-3S -
CD-27 AMP 2 Turbin pick up sensor 85202-1 -
CD-39 DEUTSCH 3 Main pump pressure switch DT06-3S -
CD-40 DEUTSCH 3 Steering pump pressure switch DT06-3S -
CD-41 DEUTSCH 4 Boom down rpessure switch DT06-4S
CD-45 DEUTSCH 2 WIF sensor DT06-2S-EP06 -
CD-46 AMP 3 Output speed sensor 282087 -
CD-47 AMP 2 Gear chain senser 85202-5 -
CD-48 AMP 2 Oil filter 282080 -
CD-49 AMP 2 Converter sensor 85202-1 -
CD-73 AMP 2 Speed sendsor 174352-2 -

7-58
2. CONNECTION TABLE FOR CONNECTORS
1) 58-L TYPE CONNECTOR
No. of
Receptacle connector (female) Plug connector (male)
pin

1 1

S813-030100 S813-130100

1 2 1 2

S813-030200 S813-130200

7-59
 2) PA TYPE CONNECTOR
No. of
Receptacle connector (female) Plug connector (male)
pin

2 5 1 3

1 3 2 5

S811-005002 S811-105002

3 7 1 4

1 4 3 7
S811-007002 S811-107002

4 9
1 5

1 5
4 9
S811-009002 S811-109002

5 11 1 6

11

1 6 5 11
S811-011002 S811-111002

7-60
No. of
Receptacle connector (female) Plug connector (male)
pin

6 13 1 7

13

1 7 6 13
S811-013002 S811-113002

1 9
8 17

17

1 9 8 17
S811-017002 S811-117002
110 21 1 11

21

1 11 1
10 21

S811-021002 S811-121002

7-61
3) J TYPE CONNECTOR
No. of
pin Receptacle connector (female) Plug connector (male)

1 2
1

2 12
S816-002001 S816-102001

2 3 1

3 1 2

S816-003001 S816-103001

3 1 4 2

4 2 3 1

S816-004001 S816-104001

8 5 2
6 3 1

8 5 2 6 3 1
S816-008001 S816-108001

7-62
4) SWP TYPE CONNECTOR
No. of
pin Receptacle connector (Female) Plug connector (male)

1 1

S814-001000 S814-101000

2 1

1 2

S814-002000 S814-102000

3 1

2 1 23

S814-003000 S814-103000

2 4 1 3

1 3 2 4

S814-004000 S814-104000

7-63
No. of
pin Receptacle connector (female) Plug connector (male)

3 6 1 4

3 6
1 4
S814-006000 S814-106000
4 8 1 5

4 8
1 5
S814-008000 S814-108000

4 12 1 9

12

4 12
1 9

S814-012000 S814-112000

3 14 11
1

14

1 11 3 14

S814-014000 S814-114000

7-64
 5) CN TYPE CONNECTOR
No. of
pin Receptacle connector (female) Plug connector (male)

1 1

S810-001202 S810-101202

2 2

1 1

S810-002202 S810-102202

3 2

1 2 1 3

S810-003202 S810-103202
2 4 1 3

1 3 2 4

S810-004202 S810-104202

7-65
No. of
pin Receptacle connector (female) Plug connector (male)

3 6 1 4

1 4 3 6
S810-006202 S810-106202

4 8 1 5

1 5 4 8
S810-008202 S810-108202

7-66
6) ITT SWF CONNECTOR
No. of
pin Receptacle connector (female) Plug connector (male)

10

1 12

11
SWF589790

7) HW090 SEALED CONNECTOR

No. of
pin Receptacle connector (female) Plug connector (male)

6 3

4
6

6189-0133

8) MWP02F-B CONNECTOR
No. of
pin Receptacle connector (female) Plug connector (male)

2 1

2
PH805-02028

7-67
9) AMP ECONOSEAL CONNECTOR
No. of
pin Receptacle connector (female) Plug connector (male)

12
1

12
13 24
36
25
24 36 1
13
36
25
344111-1
344111-1 344108-1
344108-1

10) AMP TIMER CONNECTOR

No. of
pin Receptacle connector (female) Plug connector (male)

85202-1

11) AMP 040 MULTILOCK CONNECTOR

No. of
pin Receptacle connector (female) Plug connector (male)

12 1 6

7 12
174045-2

7-68
12) KET 090 WP CONNECTORS
No. of
pin Receptacle connector (female) Plug connector (male)

2 1

MG640795

13) ITT SWF CONNECTOR

No. of
pin Receptacle connector (female) Plug connector (male)

2
10

1 10

SWF593757

14) MWP NMWP CONNECTOR

No. of
pin Receptacle connector (female) Plug connector (male)

1
1

NMWP01F-B

7-69
 15) DEUTSCH DT CONNECTORS
DT 06 - 3S - ★★★★

Modifications (see below)

Number of contacts (P : Pin, S : Socket)
04 : Receptacle, 06 : Plug
Deutsch connetors
※ Modification
E003 : Standard end cap - gray
E004 : Color of connector to be black
E005 : Combination - E004 & E003
EP04 : End cap
EP06 : Combination P012 & EP04
P012 : Front seal enhancement - connectors color to black for 2, 3, 4 & 6pin

No. of
pin Receptacle connector (female) Plug connector (male)

1 2 2 1
2

DT06-2S DT04-2P

2 1 1 2

3 3

DT06-3S DT04-3P

4 1 1 4

3 2 2 3

DT06-4S DT04-4P

7-70
No. of
pin Receptacle connector (female) Plug connector (male)

6 1 1 6

4 3 3 4

DT06-6S DT04-6P

4 5 5 4

1 8
8 1

DT06-8S DT04-8P

7 6
6 7

12

1 12 12 1

DT06-12S DT04-12P

7-71
16) ECONOSEAL J TYPE CONNECTORS
No. of
pin Receptacle connector (female) Plug connector (male)

S816-001002 S816-101002

1 2 1
2

S816-002002 S816-102002

S816-003002 S816-103002

S816-004002 S816-104002

7-72
No. of
pin Receptacle connector (female) Plug connector (male)

S816-006002 S816-106002

S816-008002 S816-108002

10

S816-010002 S816-110002

12

S816-012002 S816-112002

7-73
No. of
pin Receptacle connector (female) Plug connector (male)

15

368301-1 2-85262-1

17) METRI-PACK TYPE CONNECTOR

No. of
Receptacle connector (female) Plug connector (male)
pin

12040753

18) DEUTSCH MCU CONNECTOR

No. of
Receptacle connector (Female) Plug connector (Male)
pin

5
1 6
11 1
10
2
3
11 4
5
21
6
40 21 31
32
7
8
9
33 10
34
35

31 36
37
20
30
20
38
39
35 40

36
30
40

DRC26-40SA/B/C

7-74
GROUP 6 TROUBLESHOOTING

1. WHEN STARTING SWITCH IS TURNED ON, CLUSTER AND MONITOR LAMP DOES NOT
LIGHT UP
·Before carrying out below procedure, check all the related connectors are properly inserted and the
fuse [CN-36] No.12 is not blown out and ON/OFF of bulb.
·After checking, connect the disconnected connectors again immediately unless otherwise
specified.

Cause Remedy
YES
Defective cluster Replace
Check voltage Defective monitor Replace
between CN-56
(1), CN-57(1) and
chassis
Disconnection in Repair or
NO
wiring harness or replace
poor contact (after clean)
between CN-56
(1), CN-57 (1)
and fuse No. 12

MONITOR

CN-57

CLUSTER
FUSE[CN-36]
1
No.12
CN-56

Check voltage
YES 20 ~ 30 V
NO 0V
7609A7EL24

7-75
2. WHEN BATTERY LAMP LIGHTS UP (engine is started)
·Before carrying out below procedure, check all the related connectors are properly inserted.
·After checking, connect the disconnected connectors again immediately unless otherwise
specified.
Cause Remedy
YES
Check voltage Defective Replace
YES controller
between CN-58A
(B36) and chassis
NO Disconnection in Repair or replace
Voltage : 27.5~30V wiring harness or (after clean)
poor contact
Check voltage between CN-58A
YES between CN-6
(B36) and CN-6 (49)
(49) and chassis
YES
Voltage : 26~30V Disconnection in Repair or replace
wiring harness or (after clean)
Check voltage poor contact
Check voltage between CN-13 between CN-13
NO
between (8) and chassis (8) and CN-6 (49)
alternator
terminal "2" and Disconnection in Repair or replace
chassis NO
wiring harness or (after clean)
Voltage : 26~30V poor contact
Starting switch : ON
between CN-13
(8) and alternator
terminal " 2 "

Defective alternator Replace

NO

CONTROLLER(MCU)

49
ALTERNATOR
B36 8 " 2 " TERMINAL
CN-6 CN-13
CN-58A
Check valtage
YES 20 ~ 30 V
NO 0V 75797EL30

7-76
3. WHEN PARKING SOLENOID DOES NOT WORK
·Before carrying out below procedure, check all the related connectors are properly inserted and the
fuse [CN-36] No.29 is not blown out.
·After checking, connect the disconnected connectors again immediately unless otherwise specified.

Cause Remedy
YES
Defective parking Replace
Check voltage brake solenoid
YES between CS-17
Check voltage (4) and chassis
YES Disconnection in Repair or replace
between CN-5
Voltage : 20~30V NO wiring harness or (after clean)
(30) and chassis
Check voltage
poor contact
between CN-71 Voltage : 20~30V
between CS-17
(2) and chassis
(4) and CN-5 (30)
Starting switch : ON
Parking switch : ON-OFF YES
Voltage : 20~30V Disconnection in Repair or replace
wiring harness or (after clean)
poor contact
Check voltage between CN-12
between CN-12 (13) and CN-5
NO
(13) and chassis
(30)
Voltage : 20~30V
Disconnection in Repair or replace
NO
wiring harness or (after clean)
poor contact
between CN-12
(13) and CN-71
(2)

YES
Difective parking Replace
Check voltage
switch
between CS-17
NO
(7) and chassis
Disconnection in Repair or replace
Voltage : 20~30V NO
wiring harness or (after clean)
poor contact
between CS-17
(7) and Fuse
No.29

PARKING SWITCH
8 FUSE [CN-36]
7
4 No.29
CN-5 CN-12
CS-17
30 13 2
1
CN-71

7609A7EL31

7-77
4. TRANSMISSION IS NOT RETURNED TO NEUTRAL WHEN PARKING BRAKE IS APPLIED
·Before carrying out below procedure, check all the related connectors are properly inserted and the
fuse [CN-36] No.29 is not blown out.
·After checking, connect the disconnected connectors again immediately unless otherwise
specified.
Cause Remedy
YES
Defective T/M Replace
control unit

Check voltage YES

Disconnection in Repair or replace
between CN-157
wiring harness or (after clean)
(21) and chassis
poor contact
Starting switch : ON Check voltage between CN-157
Parking switch : ON between CS-17
Voltage : 20~30V NO (3) and chassis (21) and CS-17(3)

YES
Voltage : 20~30V Defective switch Replace
Parking switch : ON Check voltage
between CS-17
NO
(7) and chassis
Disconnection in Repair or replace
NO
Voltage : 20~30V wiring harness or (after clean)
poor contact
between CS-17 (7)
and fuse No.29

PARKING SWITCH
8 FUSE[CN-36]
7
3 No.29
T/M CONTROL UNIT
CS-17
21

CN-157

Check resistance
YES MAX 1Ω
7609A7EL32
NO MIN 1MΩ

7-78
5. MACHINE DOES NOT TRAVEL
·Before carrying out below procedure, check all the related connectors are properly inserted and the
fuse [CN-36] No.11 (transmission controller) is not blown out.
·After checking, connect the disconnected connectors again immediately unless otherwise
specified.
·Wiring diagram : See page 7-17.
Cause Remedy
YES
Defective clutch Replace
cut-off mode
Check resistance
YES switch
between CD-4
and chassis
Is there continuity
NO
between CN-157
(38) and chassis? Defective T/M Replace
NO
control unit

Is voltage between
Defective T/M Replace
CN-157(21) and NO
chassis 20-28V? control unit

Starting switch : ON YES

Parking switch : OFF Defective Replace
Clutch cut-off parking switch
switch : ON Is there continuity
between CS-17(3)
YES
and chassis?

Disconnection Repair or replace

NO
wiring harness (after clean)
or poor contact
between CN-157
(21) and CS-17 (3)

Check resistance
YES MAX 1Ω
NO MIN 1MΩ

7-79
6. WHEN STARTING SWITCH IS TURNED ON, WIPER MOTOR DOES NOT OPERATE
·Before carrying out below procedure, check all the related connectors are properly inserted and the
fuse [CN-36] No.28 is not blown out.
·After checking, connect the disconnected connectors again immediately unless otherwise
specified. FUSE BOX
SERVICE SOCKET 1 20A
25
SPARE 20A
26
WORK LAMP_REAR 20A
27
Cause Remedy Br WIPER 20A
28
PARK
YES 20A
29
Check voltage Defective front Replace JOYSTICK-DETENT 10A
30
30A
YES between front wiper motor PRE-HEAT, FUEL WARMER
31
FAN REVERSE, ATT. 20A
wiper motor and RIDE CONTROL 10A
32
33
chassis Poor connection of Replace JOYSTIC_SWITCH 10A

Check voltage Voltage : 20~30V

NO 34

YES chassis
between CN-21(5) Starting switch : ON CN-36
Wiper switch : 1st
and chassis
Voltage : 20~30V
WIPER RY HI
Starting switch : ON Disconnection in Repair or replace Y
4
Check voltage Wiper switch : 1st NO B 3 2
1
YES between CS-12 wiring harness or (after clean) R
5
Br
(4) and chassis poor contact Br
2
3 4 5 1
between CN-21(5) CR-4
Voltage : 20~30V and CR-26(3)
Starting switch : ON WIPER RY LO
Wiper switch : OFF G
4 3 2
W
1
Y
FRONT WIPER 5
Y Y Y
3E 1 2
G LW W
Defective wiper Repair or replace 2Pf
B
2
B 3 4 5 1
NO 1B
L
3
R CR-26
Check voltage switch or (after clean) R
4
W
4 Hi 5
CS-12 (6) disconnection in M
5 Lo 6
CN-21
wiring harness or CN-102
Voltage : 20~30V poor contact
Starting switch : ON
Wiper switch : 1st
between CS-12(4)
and CR-26(4).

Disconnection in Repair or replace

NO
wiring harness or (After clean)

LOr

LW
Gr
Br

Br
G
poor contact
between CS-12(6)
and fuse [CN-36]

CS-11
CS-12
CS-5

CN-58A
WIPER INT SIG A23

A31

B02
1
2
3
4
5
6

8
7
6
5
4
3
2
1
No.28

HO

RW

BVi
BY

4BWG
Gr

W
G
L

WIPER RLY
Y

6
2
6
1

3
5

WASH SIG
C

Hi
J

C
W

II

II
J

Hi Lo
I
O

B+
C
MCU

F
L
R
O
L
R

Y 7 Lo

B 5
WB 8
BG 3

BW 2
MULTI FUNCTION SWITCH

7309S7EL33

7-80
7. WHEN STARTING SWITCH "ON" DOES NOT OPERATE
·Before carrying out below procedure, check all the related connectors are properly inserted and
and the fuse No.3 is not blown out.
·After checking, connect the disconnected connectors again immediately unless otherwise FUSIBLE LINK
MASTER SW CN-60
specified. 3R 105
3R 106
Cause Remedy CN-95
RW
YES
RW
Check voltage Defective cable Repair or replace
CS-74 BATTERY RY
YES between assembly (after clean) RW 80R
CN-60(1) and 80R
B BATTERY
chassis
Short circuit or Replace CR-1
Voltage : 20~30V NO DO-2
Check voltage defect of fusible RW
2
YES B
between CR-1 link or defective FUSE BOX
1

and chassis 10A BEACON 19 To starter

battery relay 15
20A WORK LAMP_FRONT
16 20
Voltage : 20~30V 20A MIRROR,SER.SOCKET2
17 21
20A ILL.LAMP
18
Disconnection in Repair or replace 20A HEAD LAMP
22
NO 19
Check voltage wiring harness (after clean) 20
10A BACK.STOP LAMP 23

YES between CS-2 21

20A HORN/CONVERTER 24
(1)[and CS-2(2)] or poor contact 30A AIR-CON/HEATER 1 25
22
and chassis between CS-2 23
20A FUEL WARMER 26
30A CIGAR LIGHTER
Voltage : 20~30V 24 27
(2) - CN-5(37)- W
28
CS-74-CR-1. 20A TURN LAMP 36
1
5A RADIO/ROOM LAMP 37
2
30A START KEY SWITCH R
3 38
Disconnection in Repair or replace 10A TCU 24V BATTERY
Check voltage NO 4 47
20A ECM 24V BATTERY
wiring harness (after clean) 5
48
and specific 6
20A MCU 24V BATTERY

gravity of battery or poor contact 7

20A AIR-CON/HEATER 2 CN-5
10A CLUSTER 24V BATTERY
Specific gravity : MIN 1.28
b e t we e n f u s e 8
3R
Voltage : MIN 24V No. 3 and CS-2
CN-36
(1) or defect of
start switch

Battery capacity Repair or replace

NO
too low (after clean)

RW
R
CS-2

2
6
5
4

1
B
0, I

1
H 0 I II

4
6
5

3
2
H
C ST ACC BR
START SWITCH

7579S7EL34

7-81
 FUSE BOX
1
8. WHEN STARTING SWITCH IS TURNED ON, WORK LAMP DOES NOT LIGHTS UP 2 GW
BEACON
WORK LAMP_FRONT
10A

20A
15
16
3
·Before carrying out below procedure, check all the related connectors are properly inserted, and MIRROR,SER.SOCKET2 20A
17
4 ILL.LAMP 20A
18
the fuse [CN-36] No.16, 27 is not blown out. 5 HEAD LAMP 20A
19
·After checking, connect the disconnected connectors again immediately unless otherwise 6 BACK.STOP LAMP 10A

20A
20
HORN/CONVERTER
specified. 7 21
AIR-CON/HEATER 1 30A

8 22
FUEL WARMER 20A
23
9 CIGARLIGHTER 30A
24
10
Cause Remedy 11
YES 12 SERVICE SOCKET 1 20A
25
Defective lamp Replace 20A

YES Check voltage

SEAT HEAT/AIR-RIDE
13 26
Y WORK LAMP_REAR 20A
between each FR WORK 1
W
14 27
B WIPER 20A
LAMP,LH 2
lamp and chassis 15
28
Disconnection in Repair or replace CL-5 PARK 20A
29
NO CN-7 JOYSTICK-DETENT 10A

Check voltage Voltage : 20~30V wiring harness or (after clean) FR WORK 1

W
30A
30
B PRE-HEAT, FUEL WARMER
Starting switch : ON poor contact LAMP,RH 2 31
between FAN REVERSE, ATT. 20A
YES between CL-6 (2),
CL-6 32
CN-7(14), RIDE CONTROL 10A
33
CN-6(33) and CL-5 (2), CL-22 OPTION JOYSTIC_SWITCH 10A
34
1
chassis (2), CL-23 (2) and CL-35
W
LOr
1 2
CN-7 (14), CN-6 2
B ILLUMINATION 1 5A
35
Check voltage Voltage : 20~30V 3
Starting switch : ON (33). FR WORK LAMP
between W
4 ILLUMINATION 2 5A
36
1
YES CR-3(5), B 5 CN-36
Disconnection in Repair or replace 2
CR-55(5) and NO CL-36 6
wiring harness or (after clean)
chassis 7
poor contact CL-32
RW
Voltage : 20~30V 1 8
between CN-7 2
B
Check voltage Starting switch : ON 9
(14) -CR-3 (5) and RR WORK LAMP
between 10
RW
CN-6 (33) - CR-55 1 11
B
CR-3(3), (5) 2 FR WORK LAMP RY
CL-33 12 4
CR-55(3) and B
1
3 2

chassis 13 W
Defective work Replace relay Y
5

Voltage : 20~30V
NO 14 2
lamp relay GW
3 4 5 1
Starting switch : ON RR WORK 8 15
CR-3
YES LAMP,LH CN-9
Disconnection in Repair or replace 1
RW 9
B RR WORK LAMP RY
2 10 31
wiring harness or (after clean) RR WORK CL-22 4
11 32 B 3 2
Check voltage poor contact LAMP,RH
RW RW
1
1 12 33 5
between fuse between CR-3 (3), 2
B VW
2
CN-14 34 Y
NO [CN-36] No. 16, CR-55 (3) and fuse CL-23 3 4 5 1
35 CR-55
27 and chassis [CN-36] No. 16, 27
59
Voltage : 20~30V 60
Starting switch : ON
Short circuit of Replace WORK LAMP SW
NO CN-6
fuse 12 11
1
3
Y
4
VW

6
LOr
6 7
LOr
4

9 9
3
7
R
11
12 1
12
B
CS-36

ILL & HEAD LAMP SW

12 11
1
3
4 CLUSTER
R 17 ILLUMINATION
6
6 LOr CN-56
7
4
MONITOR
R R
9 9 18 ILLUMINATION
3
7 CN-57
R
11
12 1
12
B
CS-21 7579S7EL35

7-82