INTERACTIVE SCHEMATIC

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EC-C2 E-C60
EC-C3

E-C61

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HOTKEYS (Keyboard Shortcuts)

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 UENR2535
December 2011

304 CR Mini Hydraulic Excavator

Electrical System
NAD1634-UP

© 2011 Caterpillar, All Rights Reserved Printed in U.S.A.

COMPONENT LOCATION
Schematic Machine
Component
Location Location
A/c Unit Atch C-4 5
Alarm - Travel Atch D-7 38
Alternator B-7 3
Battery 12V A-6 1
Beacon Atch D-6 9
Beacon Socket Atch D-6 9
Cluster Gage B-2 11
Control - Engine Gov Atch D-4 7
Control - Engine Shutoff Timer D-3 17
Engine - Gov Actuator Atch E-7 6
Fuse - Beacon
- Boom Lamp
- Cab Acc
- Eng Shutt Off Timer
D-3 20
- Fuel Prime Pump
- Heater
- Horn
- Key
- Monitor
- Solenoid
- Wiper
Fuse As - Box D-3 38
Fuse - Holder C-6 48
Fuse - Slow Blow B-6 48
Glow Plug C-7 22
Glow Timer E-3 23
Ground - Engine B-7 14
Heater Unit Atch C-4 5
Horn C-1 25
Lamp - Boom C-1 47
Lamp - Cab Atch E-1 10
Lamp - Canopy Atch E-5 50
Lamp - Dome Atch D-5 13
Motor - Starter B-7 37
Motor - Wiper C-2 42
Pump - Fuel Prime C-7 18
Radio Atch D-5 32
Relay - Boom Lamp A-5 4
Relay - Disable Start A-5 4
Relay - Glow A-6 4
Relay - Start A-5 4
Relay - Travel Alarm Atch (Cancel) A-4 4
Relay - Travel Alarm Atch (On) A-4 4
Sender - Coolant Temp C-7 12
Sender - Fuel A-5 19
Service Meter D-3 20
Solenoid - Ac Clutch Atch B-7 2
Solenoid - Eng Shutdown C-7 16
Solenoid - Hyd Lock D-2 27
Solenoid - PAT Valve (Atch) E-2 49
Solenoid - PAT Valve Select (Atch) E-2 49
Solenoid - Speed Select D-2 35
Switch - Gov Throttle Atch A-3 21
Switch - Heater Atch D-2 24
Switch - Horn B-2 26
Switch - Hydraulic Lock LH D-2 29
Switch - Hydraulic Lock RH B-2 34
Switch - Key B-2 28
Switch - Light D-2 30
Switch - One Touch Low Idle Atch E-1 31
Switch - Rfgt Low Press Atch B-5 33
Switch - Travel Alarm Cancel Atch D-2 39
Switch 1 - PAT Atch D-4 51
Switch 1 - Travel Press Atch D-1 40
Switch 1 - Wiper Washer Atch D-1 43
Switch 2 - Travel Press Atch D-1 40
Switch 3 - Travel Press Atch C-1 40
Switch 4 - Travel Press Atch C-1 40
Switch -Eng Press C-7 15
Tank - Washer Atch D-7 41
Terminal block C-6 48
CONNECTOR LOCATION

Schematic Machine
Connector Number
Location Location
CONN 1 C-5 4
CONN 2 B-5 4
CONN 3 B-5 4
CONN 4 B-5 4
CONN 5 C-4 7
CONN 6 A-3 44
CONN 7 C-2 47
CONN 8 C-2 46
CONN 9 E-2 45
CONN 10 E-2 45
WIRE DESCRIPTION

Wire Wire
Description
Number Color
Power Distribution Circuits
101 RD Bat (+) (Not Application Specific)
105 RD Key Sw
109 RD Alt Output (+) Term.
112 PU Main Power Rly Output
114 GN Warning Horn (Forward)
115 PK Aux Ckt
117 YL Aux Ckt
121 YL Back Alarm To Lamp
122 RD Aux Ckt
124 GN A/C
130 GN Aux Ckt
131 BR Aux Ckt
177 OR Main Brkr
180 GN Aux Ckt
190 PK Aux Ckt
Ground Circuits
200 BK Main Chassis
206 BK Bat Side Of Disconnect
Basic Machine Circuits
304 WH Starter Relay No. 1 Output
306 GN Starter Relay Coil To Neut Start SW Or Key SW
307 OR Key SW To Neutral Start SW Or VMIS Sensor Module
321 BR Backup Alarm Lamp Travel Alarm
322 GY Warning Horn (Forward)
327 PK Shutdown Solenoid
332 BU Shutdown SW To Shutdown Ctrl
Monitoring Circuits
403 GN Alternator (R) Term.
405 GY Opr Mon Oil Press. (Low Setting)
441 OR Eng Coolant Temp Gage
447 PK Fuel Level Gage
C444 YL Alternator Indicator Lamp
Accessory Circuits
506 PU Washer - Front
508 PU Radio Speaker - Left
509 WH Radio Speaker - Left (Commom)
511 BR Radio Speaker - Right
512 GN Radio Speaker - Right (Common)
515 GY Blower Motor (HI)
517 BU Blower Motor (Low)
519 PK Thermostat To Refrigerant Press. SW
521 YL A/C SW To Refrigerant SW
Lighting Circuits
603 PK Rotary Beacon
612 GY Backup Lamp
615 YL Cab Flood Lamp/Rops
616 BU Bucket Flood Lamp/Boom Flood Lamp
Control Circuits
E703 WH Travel Alarm Cancel
H740 OR HEX Governer Motor +
H741 WH HEX Governer Motor -
H742 PU HEX Governor Accel Input
H744 BU HEX Governor Low Idle
M729 PU Governer Motor Sensor Power
M730 YL Governer Motor Sensor Signal
M731 BU Governer Motor Sensor Return
817 WH Back-Up Alarm Relay
877 YL Glow Plug Magnetic SW To Glow Plug
C904 GN Relay to Relay
E953 GY Track Travel Speed SW to Solenoid
L987 WH Start Aid SW
L989 BU Oxygen Buffer Relay
N933 PU Low Idle Indicator (replaces D815-PU)
P969 BR Analog return(HEDC)
P977 PK Safety Sw to Safety Relay
R997 OR +5v Analog Sensor Power
 HARNESS and WIRE
Electrical Schematic Symbols
Symbols

Pressure Temperature Level Flow Circuit Breaker

Symbol Symbol Symbol Symbol Symbol

Symbols and Definitions

Fuse: A component in an electrical circuit that will open the circuit if too much current flows through it.

Switch (Normally Open): A switch that will close at a specified point (temp, press, etc.). The circle indicates that the component has
screw terminals and a wire can be disconnected from it.

Switch (Normally Closed): A switch that will open at a specified point (temp, press, etc.). No circle indicates that the wire cannot be
disconnected from the component.

Ground (Wired): This indicates that the component is connected to a grounded wire. The grounded wire is fastened to the machine.

Ground (Case): This indicates that the component does not have a wire connected to ground. It is grounded by being fastened to the
machine.

Reed Switch: A switch whose contacts are controlled by a magnet. A magnet closes the contacts of a normally open reed switch; it
opens the contacts of a normally closed reed switch.

Sender: A component that is used with a temperature or pressure gauge. The sender measures the temperature or pressure. Its
T
resistance changes to give an indication to the gauge of the temperature or pressure.

Relay (Magnetic Switch): A relay is an electrical component that is activated by electricity. It has a coil that makes an electromagnet
when current flows through it. The electromagnet can open or close the switch part of the relay.

Solenoid: A solenoid is an electrical component that is activated by electricity. It has a coil that makes an electromagnet when current
flows through it. The electromagnet can open or close a valve or move a piece of metal that can do work.

Magnetic Latch Solenoid: A magnetic latch solenoid is an electrical component that is activated by electricity and held latched by a
permanent magnet. It has two coils (latch and unlatch) that make electromagnet when current flows through them. It also has an
internal switch that places the latch coil circuit open at the time the coil latches.

Harness and Wire Symbols

Wire, Cable, or Harness Assembly Identification: Harness Identification Letter(s): (A, B, C, ..., AA, AB, AC, ...)
Includes Harness Identification Letters and Harness
Connector Serialization Codes (see sample).
Harness Connector Serialization Code: The "C" stands for
"Connector" and the number indicates which connector in the
harness (C1, C2, C3, ...).
AG-C4 L-C12
111-7898 3E-5179 L-C12
3E-5179
Part Number: for 1 Part Number: for
Connector Plug
Connector Receptacle
2

Plug Receptacle
Pin or Socket Number

5A
1 Deutsch connector: Typical representation
Component
of a Deutsch connector. The plug contains all Fuse (5 Amps) 9X-1123 Part Number
2 sockets and the receptacle contains all pins.
325-AG135 PK-14
1 Sure-Seal connector: Typical representation Harness identification code:
of a Sure-Seal connector. The plug and receptacle This example indicates wire group 325, Wire Gauge
2 contain both pins and sockets. wire 135 in harness "AG". Wire Color
 7 6 5 4 3 2 1

CONN 10
OPERATOR STATION OPERATOR STATION G-C6
7Y3967
P-C1
7Y3966
P-C3
7Y3967
616-G23 BU-16 1 615-P2 YL-18 1 RD-18 (10) ATCH CAB LAMP
1980852
CANOPY CANOPY H742-L7 PU-16 200-G15 BK-16 1
200-P1 BK-18
P C4
1 WH-18

H744-L8 BU-18 G-C5 P-C2 7Y3966

N933-L12 PU-18 7Y3966 7Y3967
(50) ATCH CANOPY LAMP R997-L14 OR-16 CONN 9
H-C2 P C8 P C6 1980852 P969-L13 BR-16
7Y3967 7Y3966 7Y3967
616-H5 BU-18 1 615-P3 YL-18 1 RD-18 190-L2 PK-16
190-L1 PK-14
200-H1 BK-18 1 200-P4 BK-18 1 WH-18 190-L3 PK-18
H-C3 P C9 P C7
7Y3966 7Y3967 7Y3966

CANOPY
180-G6 GN-16

CANOPY
E 180-G9 GN-16
200-G13 BK-16
200-G16 BK-16
E
G24 YL-16
H-C1 G25 GY-16
3E3382
616-H5 BU-18 1 OPERATOR STATION
2 506-G17 PU-16
200-H1 BK-18 200-H3 BK-18 3 S02-R14 GY-18 180-G8 GN-16
603-H4 PK-18 200-H2 BK-18 4 S01-R13 PU-18 180-G7 GN-16
200-H2 BK-18 603-H4 PK-18 5 S03-R15 BR-18
200-H3 BK-18 616-H5 BU-18 6 131-R3 BR-18
603-H4 PK-18 131-R4 BR-18
131-R5 BR-18
R C3 P969-L13 BR-16
131-R1 BR-18 7222-1424-40 H742-L7 PU-16

190-L1 PK-14
SOL A
CANOPY CANOPY 131-R3 BR-18 1 N933-L12 PU-18

L17
S01-R13 PU-18 2 R997-L14 OR-16
R C4 (49) ATCH PAT SOL
7123-1424-40 VALVE
131-R4 BR-18 1 1895670
S02-R14 GY-18 2
SOL B
2 5

A-C28 (23) GLOW TIMER

(49) ATCH PAT SELECT VALVE
(6) ATCH ENG GOV ACTUATOR OPERATOR STATION 4 1
7Y3958 1199896
1432269

308-A46 YL-16
200-A22 BK-18
3
A-C30 1 GND R C5 L-C6

200-A21 BK-18
1916227 1552269 7Y3967

112-A2 PU-12
L-C4 9X1054 2
NOTE B 1552273 3 131-R5 BR-18 1 190-L3 PK-18 1
MAIN RELAY
POT + 1 M729-L9 PU-16 H740-L5 OR-16 1151615 308-A45 YL-16 4 ON (KEY) S03-R15 BR-18 2
POT SIG 2 M730-L10 YL-16 H741-L6 WH-16 306-A40 GN-18 5 ST (KEY)
POT GND 3 M731-L11 BU-16 306-A41 GN-18 6 GROW RELAY H744-L8 BU-18 1
SPACE 4 M729-L9 PU-16 L987-A70 WH-18 L-C7
+M 5 H740-L5 OR-16 M730-L10 YL-16 A-C4 c0 7Y3967
-M 6 H741-L6 WH-16 M731-L11 BU-16 150-A17 RD-12 1552273 R C1 L-C8 VALVE GP (31) ATCH ONE TOUCH LOW IDLE SW
122-A76 RD-16 1 B+ 12V 7Y3966 7Y3966 1911390 1936359
200-L4 BK-18 200-A24 BK-18 2 GROUND A C32 A C30 NOTE B
327-A52 PK-16 7Y3967 7Y3967

1
3 SIG OUT
308-A44 YL-16 4 KEY ON
306-A41 GN-18 5 KEY ST E953-A69 GY-16 (35) SPEED SELECT SOL
(9) ATCH BEACON ATCH ANTENNA 6 200-A32 BK-18
1286985 XXXXXXX A-C16

R997-L14 OR-16
M731-L11 BU-16

P969-L13 BR-16
N933-L12 PU-18
H741-L6 WH-16
M730-L10 YL-16
H740-L5 OR-16
(17) ENGINE SHUTOFF TIMER CONTROL

M729-L9 PU-16

H742-L7 PU-16
H744-L8 BU-18
3E3364

200-L4 BK-18
G-C7

190-L2 PK-16
7Y3952 2317928
P977-A74 PK-16 1
(27) HYD LOCK SOL
122-G3 RD-16 1 (13) ATCH DOME LAMP (7) ATCH ENG GOV CONT 200-A31 BK-18 2
2 1396332 L-C3 1557553
200-G12 BK-16 1552264 NOTE B
603-G22 PK-16 122-G2 RD-16 190-L2 PK-16 1 RD +B 403-A54 GN-18
200-G14 BK-16 122-G3 RD-16 H744-L8 BU-18 2 BU L/I SW
180-G5 GN-16 G-C4 (32) ATCH RADIO 200-L4 BK-18 3 BK GND 200-A23 BK-18
(9) ATCH BEACON SOCKET 511-G20 BR-16 7Y3968 2034453 (ISJ) R997-L14 OR-16 4 WH IN 5V
2071686 512-G21 GN-16 1 H742-L7 PU-16 5 GN IN SIG
NOTE C 509-G19 WH-16 511-G20 BR-16 2 RH SPK (+) P969-L13 BR-16 6 BR IN GND A-C25
508-G18 PU-16 180-G5 GN-16 N933-L12 PU-18 7Y3952

OPERATOR STATION
3 +12 VOLT 7 YL L/I OUT
508-G18 PU-16 4 LH SPK (+) 8
5

1
2

195-A20 YL-16
512-G21 GN-16 H740-L5 OR-16
200-G12 BK-16
6
7
RH SPK (-)
GROUND H741-L6 WH-16
1
2
RD
BU
M+
M-
- + OPERATOR STATION (43) ATCH WIPER WASHER SW 1
122-G2 RD-16 8 +12V MEM M729-L9 PU-16 3 GN POT 5V 112-A4 PU-10 2229363

512-G21 GN-16
511-G20 BR-16
200-G12 BK-16
200-G14 BK-16
603-G22 PK-16
122-G2 RD-16
122-G3 RD-16
509-G19 WH-16 9 LH SPK (-) M731-L11 BU-16 4 YL POT GND 112-A5 PU-10
ANTENNA M730-L10 YL-16 5 WH POT SIG (20) SERVICE METER C548-A90 PK-16 G-C3
6T7337 124-A77 GN-14 7Y3958 W

180-A18 GY-16
6
P
L-C2 323-A51 WH-18 180-G7 GN-16 1 L
G-C8 3E3382 105-A1 RD-10 G24 YL-16 2
7Y3952 114-A10 RD-18 G25 GY-16 3
508-G18 PU-16 1 + 125-A12 RD-14 506-G17 PU-16 4
509-G19 WH-16 122-A11 RD-16 180-G8 GN-16
D D
2 - 5
149-A13 RD-16 A-C20 6
H B B
ATCH SPEAKER LH 7Y3954
L (24) ATCH HEATER SW
2034455 200-A82 BK-18 1 BU/BK
(38) BOX AS.-FUSE M 0996220
231-7924 517-A86 BU-18 2 BU/WH
(20) FUSE(5A) 515-A85 GY-18 3 BK
B
131-R5 BR-18 141-2759
131-R4 BR-18 (20) FUSE(10A)
131-R3 BR-18 113-8490
ATCH PAT CONT 131-R1 BR-18 (20) FUSE(15A) (29) HYD LOCK SW LH
N c3 131-R2 BR-18
1462829 1552273 (51) ATCH PAT SW 1 113-8491 2500989
N C6 A C23
1462825
+ BATTERY RD/GN 1 131-R2 BR-18 S01-R13 PU-18
7123-7923-40 1552261 OPERATOR STATION
SOL(L) WH/YL 2 S02-R14 GY-18 S02-R14 GY-18 TILT(L)
1 150-A15 RD-10 1 10A 1 308-A48 YL-16 1
SOL(R) RD/YL 3 S01-R13 PU-18 S03-R15 BR-18 TILT(R)
WH 2 L02-R10 WH-18 2 10A 1 330-A53 YL-16 2
SELECT VALVE BU/YL 4 S03-R15 BR-18 L14
200-R8 BK-18 ANGLE(L)
RD 3 L01-R9 RD-18 150-A16 RD-10 1 15A 1
(41) ATCH WASHER TANK 5 L01-R9 RD-18 ANGLE(R)
BU 4 L04-R12 BU-18 2 5A 1 (40) ATCH TRAVEL PRESS SW 1
1917524 E-C7 SW TILT(L) WH 6 L02-R10 WH-18 L02-R10 WH-18 GN 5 L03-R11 GN-18 3 10A 1 K-C2 1327748
7Y3952 SW ANGLE(L) BU 7 L04-R12 BU-18 L03-R11 GN-18 BK 6 200-R8 BK-18 1 5A 1 (30) LIGHT SW 1552269

OPERATOR STATION
1 506-E17 PU-18 8 L04-R12 BU-18 2 5A 1 2366782 817-K7 WH-18 1
PUMP 2 200-E4 BK-18 SW TILT(R) RD 9 L01-R9 RD-18 112-A3 PU-10 3 5A 1 A-C21 200-K1 BK-18 2

L987-A70 WH-18
7Y3957

C548-A90 PK-16
L03-R11 GN-18

323-A51 WH-18
306-A40 GN-18

403-A54 GN-18

124-A77 GN-14
SW ANGLE(R) GN 10

122-A76 RD-16
122-A11 RD-16

114-A10 RD-18
125-A12 RD-14
149-A13 RD-16
200-A22 BK-18
200-A24 BK-18
200-A23 BK-18

327-A52 PK-16
200-A21 BK-18

150-A16 RD-10
308-A44 YL-16
308-A45 YL-16
308-A46 YL-16

105-A1 RD-10
112-A4 PU-10
112-A5 PU-10

150-A15 RD-10
200-A36 BK-18

RD-12
112-A2 PU-12
11 2 WH-18

RD-10
RD-10
RD-10
GROUND BK 12 200-R7 BK-18 616-A63 BU-18 3 YL-18
195-A20 YL-16 200-A35 BK-18 4
321-E8 BR-18 200-R7 BK-18 129-A78 BU-16 1 10A 1 A625-A66 BR-18 1 BK-18 (40) ATCH TRAVEL PRESS SW 2

150-A17
150-A14
150-A16
150-A15
200-E5 BK-18 200-R8 BK-18 180-A18 GY-16 1 10A 2 RD-18 K-C3 1327748
200-R6 BR-16 180-A19 GN-16 1 10A 1 1552269
(38) ATCH TRAVEL ALARM 603-A89 PK-18 1 10A 2 (39) ATCH TRAVEL ALARM CANCEL SW 817-K8 WH-18 1

512-G21 GN-16
511-G20 BR-16
603-G22 PK-16
200-G12 BK-16
200-G14 BK-16
180-G5 GN-16
122-G3 RD-16
122-G2 RD-16
1612539 506-G17 PU-16 113-A6 OR-18 1 5A 3 1992428 200-K3 BK-18 2
603-G22 PK-16 A-C22
616-G23 BU-16 1552272

OPERATOR STATION
122-G3 RD-16 E703-A68 WH-18 1 WH-18
122-G2 RD-16 616-A64 BU-18 4 YL-18 (40) ATCH TRAVEL PRESS SW 3
ENGINE 200-G13 BK-16
180-G6 GN-16
180-G5
180-G6
GN-16
GN-16
200-A38 BK-18
200-A37 BK-18
3
BK-18
K-C4
1552269
1327748

817-K6 WH-18

817-K10 WH-18
2

817-K7 WH-18
817-K8 WH-18
817-K9 WH-18
180-G7 GN-16 180-G9 GN-16 122-G2 RD-16 CONN 5 200-A31 BK-18 817-K9 WH-18

200-K2 BK-18
BU-18 1

200-K1 BK-18
200-K4 BK-18
200-K5 BK-18
200-K3 BK-18
E-C13 200-G16 BK-16 180-G8 GN-16 122-G3 RD-16 G-C1 A-C24 200-A32 BK-18 200-K4 BK-18 2
7Y3967 180-G8 GN-16 180-G7 GN-16 3E3382 1552273
1 327-E12 PK-16 180-G9 GN-16 122-G1 RD-14 1 122-A75 RD-16
506-G17 PU-16 180-G4 GN-14 180-G4 GN-14 2 129-A78 BU-16 200-A34 BK-18 (40) ATCH TRAVEL PRESS SW 4

129-A78 BU-16
206-E6 BK-16 200-G15 BK-16 200-G16 BK-16 200-G10 BK-16 200-A81 BK-16 200-A83 BK-18

L987-A70 WH-18
1 3 K-C5

C548-A90 PK-16
323-A51 WH-18
124-A77 GN-14

180-A19 GN-16

306-A40 GN-18

403-A54 GN-18
1327748

122-A75 RD-16

149-A13 RD-16
122-A76 RD-16
122-A11 RD-16

114-A10 RD-18

125-A12 RD-14

150-A14 RD-10

200-A21 BK-18
200-A22 BK-18
200-A23 BK-18
200-A24 BK-18

327-A52 PK-16

603-A89 PK-18
308-A44 YL-16
308-A45 YL-16
308-A46 YL-16
113-A6 OR-18
105-A1 RD-10
112-A2 PU-12
112-A3 PU-10
112-A4 PU-10
E-C14 616-G23 BU-16 200-G15 BK-16 506-G17 PU-16 4 506-A84 PU-18 200-A35 BK-18 1552269

112-A5PU-10
(16) ENG SHUTDOWN SOL 7Y3967 122-G2 RD-16 200-G14 BK-16 603-G22 PK-16 5 603-A89 PK-18 200-A36 BK-18 817-K10 WH-18 1
1958411
180-G5 GN-16 200-G13 BK-16 616-G23 BU-16 6 616-A94 BU-16 200-A37 BK-18 200-K5 BK-18 2
200-G12 BK-16 200-G12 BK-16 200-A38 BK-18
(15) ENG PRESS SW 603-G22 PK-16 200-G11 BR-14 200-A82 BK-18
1958453
200-G14 BK-16 330-A53 YL-16 CONN 8
122-G3 RD-16 200-G10 BK-16 308-A48 YL-16 K-C1
405-E14 GY-18 200-G11 BR-14 515-A85 GY-18 3E3364
517-A86 BU-18 817-A65 WH-18 1 817-K6 WH-18
616-A62 BU-18 200-A33 BK-18 2 200-K2 BK-18
616-A94 BU-16
SPEED SELECT SW
(5) ATCH A/C UNIT 2445728
1919470 A-C9 616-A63 BU-18
1552273 616-A64 BU-18 180-A19 GN-16 1

OPERATOR STATION
(12) COOLANT TEMP SENDER ATCH GROUND CAB 1 200-A79 BK-14 A625-A66 BR-18 E953-A69 GY-16 2
2230309 G-C9 WATER VALVE MOTOR ACTUATOR 2 C548-A93 PK-16 E703-A68 WH-18
7Y3952 COMPRESSOR RELAY 3 519-A87 PK-18 E953-A69 GY-16 A-C31
441-E16 OR-18 511-G20 BR-16 1 4 124-A77 GN-14 P977-A74 PK-16 7Y3967
+ ATCH SPEAKER RH BLOWER MOTOR

L987-A70 WH-18

E703-A68 WH-18
E953-A69 GY-16
A625-A66 BR-18
C548-A90 PK-16

P977-A74 PK-16
323-A51 WH-18
ENGINE

124-A77 GN-14

180-A19 GN-16

306-A40 GN-18

403-A54 GN-18
149-A13 RD-16
RD-16

122-A75 RD-16

114-A10 RD-18
125-A12 RD-14
150-A14 RD-10

515-A85 GY-18
616-A62 BU-18
ENGINE

BU-16
PU-18
BU-16

129-A78 BU-16

517-A86 BU-18
616-A94 BU-16
BK-16
PK-18

603-A89 PK-18

200-A25 BK-18
200-A21 BK-18
200-A23 BK-18
200-A24 BK-18
200-A22 BK-18

327-A52 PK-16

200-A31 BK-18
200-A32 BK-18
200-A34 BK-18
200-A82 BK-18
200-A83 BK-18
308-A44 YL-16
308-A45 YL-16
308-A46 YL-16

308-A48 YL-16
330-A53 YL-16
512-G21 GN-16 - 521-A88 YL-18 322-A50 GY-18 (25) HORN

113-A6 OR-18
105-A1 RD-10
T° 2 2034455 COMPRESSOR RELAY 5 1
6 2459398

CONN 7

122-A75
129-A78
200-A81
506-A84
603-A89
616-A94
F-C1
(18) FUEL PRIME PUMP (5) ATCH HEATER UNIT 3E3364 (47) BOOM LAMP
C 2110804 E- 111
7Y3952
2178515 NOTE C A-C8
7Y3954
616-A61 BU-18
200-A28 BK-18
1
2
616-F2 BU-18
200-F1 BK-18
2330099
C
1 +BATTERY 1 C548-A92 PK-16
PUMP 2 LOW 2 517-A86 BU-18
HIGH 3 515-A85 GY-18

OPERATOR STATION
323-E10 WH-18

405-E14 GY-18

506-E17 PU-18
200-E3 BK-18

206-E6 BK-16

321-E8 BR-18
200-E4 BK-18
200-E5 BK-18
327-E12 PK-16

200-A29 BK-16
200-A30 BK-14
200-A79 BK-14
200-C4 BK-16
200-G16 BK-16
RELAY PANEL 180-G9 GN-16

E703-A68 WH-18
L987-A70 WH-18

E953-A69 GY-16
A625-A66 BR-18
C548-A90 PK-16

P977-A74 PK-16

WH-18
323-A51 WH-18
124-A77 GN-14

403-A54 GN-18
306-A40 GN-18

180-A19 GN-16
114-A10 RD-18
125-A12 RD-14
149-A13 RD-16
150-A14 RD-10

515-A85 GY-18
506-A84 PU-18

616-A62 BU-18
517-A86 BU-18
200-A25 BK-18

327-A52 PK-16

BK-14
BK-18
BK-14
BK-18
BK-18
BK-18
BK-16
BK-18
BK-18
308-A43 YL-16
308-A47 YL-16
308-A44 YL-16
308-A45 YL-16
308-A46 YL-16
308-A48 YL-16

330-A53 YL-16
113-A6 OR-18
105-A1 RD-10
CONN 1
200-A29 BK-16
200-A30 BK-14
200-A79 BK-14
200-R6 BR-16

L
206-E6 BK-16

200-L4 BK-18

200-C4 BK-16
200-E2 BK-16

E-C1 A-C5 G-C2

817-A65
200-A80
200-A33
GND

200-A30
200-A31
200-A32
200-A34
200-A81
200-A82
200-A83
1552252 3E5179 7Y3957
MOTOR
(48) TERMINAL-BLOCK 1 1 G24 YL-16
7Y-5499 304-E7 WH-14 2 304-A39 WH-14 °T 3 200-G13 BK-16 SYMBOL DESCRIPTION

OPERATOR STATION
(48) FUSE HOLDER 321-E8 BR-18 3 321-A49 BR-18 P B+
4 180-G6 GN-16
185-1290 323-E9 WH-18 4 323-A51 WH-18 321-A49 BR-18 2 G25 GY-16
(22) GLOW PLUG FUSE(5A) 139-5345 327-E12 PK-16 5 327-A52 PK-16 403-A54 GN-18
1992356 CIRCUIT CONNECTED
403-E13 GN-18 6 403-A54 GN-18 405-A55 GY-18
877-WB1 YL-6 877-E20 YL-18 1 5A 1 405-E14 GY-18 7 405-A55 GY-18 439-A56 YL-18 (42) WIPER MOTOR
441-E16 OR-18 8 441-A57 OR-18 441-A57 OR-18 1396351
877-E19 YL-10 506-E17 PU-18 9 506-A84 PU-18 323-A51 WH-18 N-C2 N-C1 CIRCUIT NOT CONNECTED
200-E2 BK-16 GROUND CHASSIS 521-E18 YL-18 10 521-A88 YL-18 327-A52 PK-16 7Y3957 1207724
206-E6 BK-16 439-E15 YL-18 11 439-A56 YL-18 506-A84 PU-18 1 N3 YL-16 1 ELECTRICAL CONNECTION TO
191- RD-6 109-E1 RD-6 304-E7 WH-14 C444-E21 YL-16 12 C444-A67 YL-16 521-A88 YL-18 3 200-N2 BK-16 3
321-E8 BR-18 C444-A67 YL-16 4 180-N1 GN-16 4 MACHINE STRUCTURE
(48) SLOWBLOW FUSE 323-E9 WH-18 304-A39 WH-14 113-A7 OR-18 2 N4 GY-16 2
327-E12 PK-16 113-A9 OR-18 INTERNAL ELECTRICAL CONNECTION
439-E15 YL-18

250-3109
877-E19 YL-10

403-E13 GN-18 RELAY PANEL 125-A12 RD-14 TO SURFACE OF COMPONENT

101-1 RD-00 1 50A 1 405-E14 GY-18 149-A13 RD-16
E C10 101-2 RD-00 1 50A 1 439-E15 YL-18 200-C4 BK-16 200-A29 BK-16
CONNECTOR

OPRATOR STATION
7Y3952 E C9 441-E16 OR-18 200-A30 BK-14

E703-A68 WH-18
L987-A70 WH-18
CONN 2

A625-A66 BR-18
C548-A90 PK-16

P977-A74 PK-16
817-A65 WH-18
323-A51 WH-18
124-A77 GN-14

306-A40 GN-18

403-A54 GN-18
125-A12 RD-14
150-A14 RD-10
149-A13 RD-16

515-A85 GY-18

114-A10 RD-18
506-A84 PU-18
517-A86 BU-18
616-A62 BU-18
L B 7Y3995

200-A83 BK-18
200-A82 BK-18
200-A80 BK-14
200-A30 BK-14

327-A52 PK-16

200-A25 BK-18
308-A47 YL-16

308-A43 YL-16
330-A53 YL-16
506-E17 PU-18 200-A79 BK-14 (28) KEY SWITCH

105-A1 RD-10
1 (33) ATCH-RFGT LOW PRESS SW
2 R P 1 403-E13 GN-18 521-E18 YL-18 1251642 M-C2 M-C1 C-C14 306-A40 GN-18 124-A77 GN-14 9G7641
H#

OR-18
OR-18
OR-18
OR-18
200-CE1 BK-0 E C444-E21 YL-16 1321847 3E3364 1552269 307-A42 OR-16 200-A79 BK-14 CIRCUIT GROUPING DESIGNATION
(3) ALTERNATOR 150- RD-10 C548-M1 PK-16 1 C548-A91 PK-16 308-A47 YL-16 517-A86 BU-18 R
G-C10
1992358 519-M2 PK-18 2 519-A87 PK-18 323-A51 WH-18 515-A85 GY-18 308-A43 YL-16 XXXXXXX
CIGAR LIGHTER
RELAY PANEL 327-A52 PK-16 519-A87 PK-18 180-G9 GN-16 1 1396341 ATCH WIRE, CABLE, COMPONENT

113-A9
113-A8
113-A7
CONN 3

113-A6
C OFF
403-A54 GN-18 521-A88 YL-18 S ON NOTE B
C-C1 A-C1 405-A55 GY-18 C548-A92 PK-16 307-A42 OR-16
150-A14 RD-10

3E5179 1552252 ST G-C11

(14) ENGINE GROUND 441-A57 OR-18 C548-A93 PK-16 XXXXXXXX
113-C1 OR-18 113-C1 OR-18 1 113-A7 OR-18 447-A58 PK-18 105-A1 RD-10
B SPLICE
L5
125-C2 RD-14 125-C2 RD-14 2 125-A12 RD-14 439-A56 YL-18 113-A7 OR-18 200-G16 BK-16
149-C3 RD-16 149-C3 RD-16 3 149-A13 RD-16 506-A84 PU-18 113-A9 OR-18 BLADE, SPADE, RING OR SCREW
200-C4 BK-16 304-C8 WH-14 4 304-A39 WH-14 519-A87 PK-18 125-A12 RD-14
304-C8 WH-14 306-C10 GN-18 5 306-A40 GN-18 521-A88 YL-18 149-A13 RD-16 (34) HYD LOCK SW RH TERMINAL
150-WA1 RD-10 306-C10 GN-18 307-C11 OR-18 6 307-A42 OR-16 616-A59 BU-16 200-A30 BK-14 2500989
323-E11 WH-18 150-WA1 RD-10 307-C11 OR-18 308-C12 YL-16 7 308-A47 YL-16 817-A65 WH-18 200-A79 BK-14 NOTE B
C444-E21 YL-16 323-E9 WH-18 308-C12 YL-16 447-C13 PK-18 8 447-A58 PK-18 A625-A66 BR-18 306-A40 GN-18 330-A53 YL-16
200-E4 BK-18 447-C13 PK-18 616-C14 BU-16 9 616-A59 BU-16 C444-A67 YL-16 308-A47 YL-16 P977-A72 PK-16
200-E3 BK-18 200-E5 BK-18 616-C14 BU-16 A625-C15 BR-18 10 A625-A66 BR-18 C548-A91 PK-16 323-A51 WH-18
200-E4 BK-18
200-E5 BK-18
200-E3 BK-18 A625-C15 BR-18
L987-C16 WH-18
L987-C16 WH-18
P977-C17 PK-18
11
12
L987-A70 WH-18
P977-A73 PK-16
E703-A68 WH-18
L987-A70 WH-18
327-A52 PK-16
403-A54 GN-18 A-C11
7Y3967
(26) HORN SW ABBREV COLOR
206-E6 BK-16 200-E2 BK-16 P977-C17 PK-18 506-A84 PU-18 105-A1 RD-10 1936358
321-E8 BR-18 206-E6 BK-16 P977-A73 PK-16 519-A87 PK-18 113-A8 OR-18 114-A10 RD-18
RD RED
1
323-E10 WH-18 304-E7 WH-14 P977-A72 PK-16 521-A88 YL-18 114-A10 RD-18
323-E9 WH-18 321-E8 BR-18 P977-A74 PK-16 616-A62 BU-18 200-A29 BK-16
B 323-E11 WH-18 327-E12 PK-16
403-E13 GN-18
405-E14 GY-18
200-A28
322-A50
BK-18
GY-18
817-A65 WH-18
A625-A66 BR-18
C548-A93 PK-16 105-A1 RD-10
200-A28 BK-18
200-A25 BK-18
200-A26 BK-18
322-A50 GY-18 1
A-C12
7Y3967
WH WHITE B
327-E12 PK-16 441-E16 OR-18 113-A9 OR-18 616-A59 BU-16 C548-A92 PK-16 113-A8 OR-18 200-A27 BK-18 OR ORANGE
ENGINE

405-E14 GY-18 506-E17 PU-18 321-A49 BR-18 616-A60 BU-18 C548-A90 PK-16 114-A10 RD-18
149-C3 RD-16
ENGINE

113-C1 OR-18
125-C2 RD-14

441-E16 OR-18 521-E18 YL-18 817-A65 WH-18 616-A62 BU-18 C548-A91 PK-16 200-A25 BK-18 (11) CLUSTER GAGE
YL YELLOW
A-C14
CONN 4
L987-C16 WH-18
A625-C15 BR-18

2483862
P977-C17 PK-18
306-C10 GN-18
307-C11 OR-18

1636659
616-C14 BU-16
447-C13 PK-18

506-E17 PU-18 E703-A68 WH-18 308-A43 YL-16 307-A42 OR-16

304-C8 WH-14

308-C12 YL-16
200-C7 BK-18
200-C6 BK-18
200-C5 BK-18
200-C4 BK-16

C444-E21 YL-16 A-C6 J-C1 E703-A68 WH-18 330-A53 YL-16 308-A43 YL-16 616-A60 BU-18 1 BACK LIGHT

PK PINK
1552272 3E3376 L987-A70 WH-18 322-A50 GY-18 405-A55 GY-18 2 ENG OIL PRESS. SW
521-E18 YL-18 113-A9 OR-18 1 113-J1 OR-18 200-A28 BK-18 P977-A74 PK-16 330-A53 YL-16 439-A56 YL-18 3 HEATER RELAY
321-A49 BR-18 2 321-J4 BR-18 322-A50 GY-18 200-A28 BK-18 405-A55 GY-18 4 ONE TOUCH LOW IDLE
RELAY PANEL

BK BLACK
RELAY PANEL

817-A65 WH-18 3 817-J6 WH-18 616-A59 BU-16 200-A29 BK-16 200-A28 BK-18 439-A56 YL-18 5
E703-A68 WH-18 4 E703-J7 WH-18 616-A60 BU-18 307-A42 OR-16 200-A29 BK-16 441-A57 OR-18 113-A8 OR-18 6 + BATTERY 12V
616-A62 BU-18 322-A50 GY-18 307-A42 OR-16 447-A58 PK-18 7
1 405-A55 GY-18 322-A50 GY-18 616-A60 BU-18 200-A26 BK-18 8 GRD GY GRAY
101-CA2 RD-00

E-C12 616-A61 BU-18 439-A56 YL-18 616-A60 BU-18 C444-A67 YL-16 9

7Y3967
113-J1 OR-18
441-A57 OR-18
447-A58 PK-18
405-A55 GY-18
447-A58 PK-18
P977-A72 PK-16 447-A58 PK-18
441-A57 OR-18
10
11
FUEL TANK UNIT
COOLANT TEMP SENDER PU PURPLE
(2) ATCH AC CLUTCH SOL 321-J4 BR-18 616-A60 BU-18 439-A56 YL-18 C444-A67 YL-16 12 ALT CHRAGE
1919028 817-J6 WH-18
E703-J7 WH-18
C444-A67 YL-16
P977-A72 PK-16
441-A57 OR-18
C444-A67 YL-16
BR BROWN
E-C8 150-A14 RD-10 P977-A72 PK-16
205-7460
GN GREEN
G
1 304-E7 WH-14
S
200-A27 BK-18
BU BLUE
113-C1 OR-18
L987-C16 WH-18

A-C15

OPERATOR STATION
306-C10 GN-18
A625-C15 BR-18

200-C5 BK-18

P977-C17 PK-18
307-C11 OR-18
616-C14 BU-16

MTR BAT
447-C13 PK-18

7Y3966
304-C8 WH-14
308-C12 YL-16

101-CA01 RD-00
306-C9 GY-16
149-C3 RD-16
200-C6 BK-18

200-C7 BK-18
306-C9 GY-16
125-C2 RD-14

NOTE A
MOTOR
(37) STARTER MOTOR (4) GLOW RELAY
HARNESS AS.
1968322 1199895
CONN 6 IDENT PART NO. LOC NOTE
113-J1 OR-18
331-J5 OR-18 113-J2 OR-18 N933-L12 PU-18 1 N933-A71 PU-18 A 248-1980 C-6
C 113-J3 OR-18 L-C5
7Y3966
A-C13
7Y3967
248-1979 C-6
D
A 5 5
5 2 NOTE A 248-1984 C-6
2 2
ENGINE
B
4 1 C 248-1982 C-8
1 1 321-J4 BR-18
4
3
4
3
3
J-C2 E 248-1983 D-9
C-C8 C-C4 7Y3958
9X1054 3E5519 F 209-8170 E-2
(4) ATCH TRAVEL ALARM RELAY(ON)
877-E19 YL-10 (4) BOOM LAMP RELAY (4) DISABLE START RELAY 2391182 G 230-7377 E-7 B
150-WA1 RD-10
1151615 1151615 214-3943 E-7 C
447-C13 PK-18

H 216-0058 I-8
E703-J7 WH-18
200-C6 BK-18

(4) START RELAY J 258-7765 C-8

2391182 E703-J9 WH-18 K 199-2425 F-1
5 2 J-C3
4 1
3E3376 N933-L12 PU-18 L 214-2093 H-11
1 (21) ATCH GOV THROTTLE SW
3 331-J5 OR-18
3
1952658 NOTE B L-C1
M 191-8082 A-10
4 1552267
P 186-4575 I-2
2 POT (GND) BR A P969-L13 BR-16
(4) ATCH TRAVEL ALARM RELAY(CANCEL)
POT (+B) WH B R997-L14 OR-16 R 210-4772 F-11
2391183
POT (SIG) GN C H742-L7 PU-16 CABLE AS.
817-J6 WH-18
CA 250-2051 A-11
CC 191-6236 A-11
OPERATOR STATION CE 171-0498 D-12
C C13 (19) FUEL SENDER WIRING AS.
1552269 1916228 WA 250-2044 B-10
WB 250-2047 D-11
A A
447-C13 PK-18 1
200-C6 BK-18 2
200-CC1 BK-00 WIRE GROUP COLOR DESCRIPTIONS
GROUND CIRCUIT.
WIRES THAT HAVE BATTERY VOLTAGE
WHEN THE KEY SWITCH IS OFF.
NEG POS
150-A14 RD-10 WIRES THAT HAVE BATTERY VOLTAGE
WHEN THE KEY SWITCH IS ON.
(1) 12V BATTERY STARTING CIRCUIT.
FRONT FRAME GND 1535656
START AID CIRCUIT.
GAUGE CLUSTER.
ENGINE CONTROL CIRCUIT.
TURN SIGNAL / WIPER / WASHER CIRCUIT.
HEATER AND AIR CONDITIONER CIRCUIT.
THIS SCHEMATIC IS FOR THE 304 CR EXCAVATOR ELECTRICAL SYSTEM
MEDIA NUMBER: UENR2535
A: STD A-C13(N933 PU-18) A-C15(200 BK-18)
B: ISJ
C: OSJ
SCHEMATIC PART NUMBER: 208-5085, CHANGE: 03, VERSION: X
NOTE A: IN CASE OF STANDARD CONNECT TO A-C36(N933 PU-18) Components are shown installed on a fully operable machine with the key and engine off, transmission shifter
AND A-C35(207 BK-18).
NOTE B: ISJ ONLY in neutral and with parking brake set.
NOTE C: OSJ ONLY
Refer to the appropriate Service Manual for Troubleshooting, Specifications and Systems Operations.

7 6 5 4 3 2 1
MACHINE COMPONENT LOCATION
VIEW ALL CALLOUTS

44 21 37 4 48 3 2 49 12
25 34 19 11 13 1 5
22
46
28
26
9
42
18
16
14
27 15

40 35

51 41

45 6

10 39 17 23 33 32 43 7 30 24 38
50 20 31 29

45 50 10 24 44 39 43 21 13 32 9
38

28
3
47 5 29 1 42 33 51 26 31 30 11
22
12
18
49
37
41

15

48

40 19 46 23 17 7 4 16 14 6
25 34 35 20 27