Service Training

Linde IC Engined Truck

H40D H40T H45D H45T H50-500T
H50-500D

Series 394

Edition 01/2005

This service document is provided for use only and remains the exclusive property of Linde AG,
Linde Material Handling Division.

Service Training – 394 804 2401 EN – 01/2005

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History of changes

Edition 10/2004 Edition 01/2005

• Chapter 1: Adjustment in the valve gear • Documentation for LPG engine added.
module: VW 5415 thrust piece not applicable. • Chapter 2: Hydraulic circuit diagram separa-
ted in A4 format.
• Chapter 6: Electric circuit diagrams separated
in A4 format.
• Chapter 8: Correction in the heading of the
table for forward tilting of mast and other
editorial changes.

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Header

The Company
Everything began in the year 1904. Carl von basis of service and flexibility. We provide this
Linde and Hugo Güldner founded the “Güldner worldwide in cooperation with our marketing
Motorenwerke”, the precursor of our company. and service organisations. With vehicles which,
No-one could imagine how dynamically this busi- in the final analysis, are nothing else than the
ness would expand in the decades to follow. technical answer to their needs. Closeness to the
Today Linde Material Handling has over seven customer is more than a word in this respect. It is
factories in Germany, France and Great Bri- lived reality.
tain and a production site in China. More than
Linde is one of the world’s leaders in the sectors
600 patents - many of them milestones in ma-
of material handling technology and hydraulics.
terial handling engineering - attest to unrivalled
The primary aim of our efforts is to offer our clients
innovative power, the basis for the success today
a convincing value for their money.Our decades
and tomorrow.
of experience in material flow and the synergetic
Today, the Linde plant II in 63701 Aschaffenburg benefits of a large company allow us to tap new
is one of the largest and most modern production potential again and again. The most recent
facilities in the world. New assembly structures example is the Linde 39X with hydrostatic direct
with only one direction of flow, trolleys without drive. A fork truck which links the fascination
drivers, new supply systems, vacuum filling of the of technology and economy as no other forklift
working hydraulics: The points were set correctly does.
from the start to achieve maximum productivity
We want to achieve a lot. We will give ever-
and quality. The distances are short, as one
ything to achieve it. To be in a strong position in
might expect. In the entire assembly process, a
tomorrow’s market you need more than yester-
Linde fork truck only travels approx. 2000 metres.
day’s success. You need to be willing to work on
It is therefore one of the fastest even before it
yourself permanently. In research and develop-
sees the light of day.
ment. In operations. And last, but not least, in
People are always at the centre of our work, no service. In this respect, we have created the best
matter what we plan, no matter what we do. On conditions with our main plants in Aschaffenburg
the one side are our employees, who receive a and the plants in Kahl, Weilbach and Ballenstedt.
lot of room for development. On the other side
Bruno Kulick
are our customers. They measure us on the
Management
basis of productivity and quality, but also on the

Structure of the training document

This training document is based on the related Section Content
seminar in the training centre and supplements Product information
it. The training document alone and without the 00
Diagnosis
accompanying training is not suited for self-study. Motor
In order to allow you find the answer to problems 01 Internal combustion engine
at hand in the training document in case of a Electric motor
necessary repair, we want to give you some Gearbox
information on how and where you can find the Hydrostatic drive axle
02
desired information. Mechanical drive axle
Drives
The training document is divided into numbered
main sections. These main sections are again Body
divided into subsections which in turn are also 03 Chassis
divided into more detailed subsections of the Operator’s compartment
related section. The numbers and headings of Running gear
the main sections and the subsections comply Steering system
with internal guidelines and are retained for Mechanical guidance
04
reasons of standardizations and continuity. Inductive guidance
Wheels and tyres
Overview of the main sections and (summarised) Brake system
their content:

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Header

Section Content of the truck.This means that individual “modules”

Controls are strung together as independent units. This
05 Controls - general is another reason why training in a our training
Display elements centre is indispensable.
Electrical / electronic installation We point out that a list of all the special tools and
Electrical / electronic installation test equipment used for this vehicle, including
06
- general part number, use and illustration, can be retrie-
Electronic controls ved in the diagnostic software “Truck Expert”
Hydraulic system according to type.
Working hydraulics With the introduction of the new form of the trai-
07
Hydraulic controls ning documents in the year 2004, we have made
Valves a new index. This index should also make it
Load lifting system easier to find the desired information fast. In
Load lifting system - general this connection we would like to ask you to in-
Mast form us under the e-mail address “service.trai-
08
Cylinders ning@linde-mh.de” if you miss an entry in the
Fork carriage index or if you discover a technical or formal er-
Attachments ror. We are also not free of errors and mistakes
Options and accessories and we are thankful for any support.
09 Options and accessories -
Thank you very much in advance for your assis-
general
tance and cooperation.
The training document has a modular structure,
it does not successively describe the structure

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Header

Explanation of the levels of danger notices

This document contains danger notices depicted
using international pictograms in the following le- CAUTION
vels and using the syntax “Description of Danger” Non-compliance may result in damage to or
with the possible consequences, as long as they destruction of the material.
do not already ensue from the type of danger,
Description of how to avoid possible damage or
and “Avoiding Danger” with explanations on how destruction.
to avoid danger.

NOTE
DANGER
Special attention should be paid to technical
There is direct danger to life or the danger interconnections which might not be apparent
of severe, life-threatening injuries and/or
even to a specialist.
significant property damage. Description of
cause of danger.
Description on how to avoid the existing danger. ENVIRONMENT NOTE

Follow the notices indicated here since non-

WARNING compliance may lead to environmental damage.
There is risk of severe injuries or large-scale
property damage. Description of the risk of injury
or the significant property damage.
Description on how to avoid the risk of injury or
significant property damage.

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Table of contents

0 Product information
The BR 394 diesel truck . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-1
The truck series 394 H 40 - H 50 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-1

Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-4
LTC - basic structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-4
LTC traction control codes, release 1.0.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-9
LTC - Lift Control Codes, Version 1.0.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-12
LTC codes of composite instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0-14

1 Engine
LPG engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Description of transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Technical data for BMF VR6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1
Engine block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Ribbed V-belt - installation and removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2
Compression - test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
Cylinder head - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4
Engine valve timing BMF - check and adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Cylinder head cover - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19
Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
Cooling system of BMF engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20
Coolant - draining and filling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
Coolant thermostat - housing disassembly and assembly . . . . . . . . . . . . . . . . . . . . . . 1-25
Engine electrical system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26
Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26
LPG installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
LPG installation - functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27
Vaporiser - functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29
Mixer - functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31
LPG shut-off valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-33
Gas failure cut-off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-34
LPG system leakage test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-35
Catalytic converter without Lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-36
Mixer - basic setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-36
Catalytic converter with Lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-39
Exhaust gases - composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-39
Lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-40

Diesel engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-46

Description of transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-46
Technical data for BJC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-46

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Table of contents

Special features of the 1.9-litre BJC engine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-47

The electronic engine control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-48
Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-49
Coolant temperature sending unit 0B1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-49
Engine speed sensor 0B2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51
Fuel temperature sending unit 0B3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-53
Intake pipe temperature and intake pipe pressure sensor 0B4 . . . . . . . . . . . . . . . . . . . 1-56
Needle stroke sensor 0B5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-58
Height sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-59
Control sleeve position sensor 0B3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-60
Actual speed sensor 1B1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-63
Preheating system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-64
Pre-heater system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-64
Engine glow plugs 0R1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-65
Fuel supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-67
Fuel metering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-67
Fuel quantity positioner 0B3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-70
Fuel shut-off valve 0Y1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-72
Injection timing device- replacement of O-ring on cover . . . . . . . . . . . . . . . . . . . . . . . . 1-72
Start of injectionvalve 0Y2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-73
Start of injection - governing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-76
Start of injection - dynamic check and adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-77
Injection nozzles - two-spring nozzle holder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-80
Injection nozzles - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-82
One-way restrictor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-83
Injection system - overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-85
Injection system - supply voltage check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-86
Injection pump - removal and installation, toothed belt replacment . . . . . . . . . . . . . . . . 1-87
Injection pump - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-93
Injection pump - pump and toothed belt adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-97
Engine block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-99
Ribbed V-belt - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-99
Crankshaft oil seal on pulley end - removal and installation . . . . . . . . . . . . . . . . . . . . 1-102
Crankshaft sealing flange - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . 1-106
Cylinder head - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-109
Cylinder head - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-111
Cylinder head - compression check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-113
Valve gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-114
Oil sump - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-116
Hydraulic bucket tappets - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-118
Camshaft - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-120
Vacuum pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-121
Mass air flow sensor 0B6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-123
Solenoid valve for charge pressure limitation 0Y4 . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-126
Charge air system with turbocharger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-130

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Table of contents

Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-133
Coolant thermostat - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-133
Water pump - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-134
Water pump - check wear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-135
Coolant - draining and filling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-136
Engine electrical system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-138
Alternator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-138
Replacing the engine control unit / immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-139
Self-test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-140
Self-test - introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-140
Self-test - fault finding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-141
Standardised data blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-148

2 Transmission
Description of transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Technical data of travel drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1
Linde Truck Control (LTC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
System overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3

Travel drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4

Travel drive - introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-4
Hydraulic pump control with electronic control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5
Start of delivery of the pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-11
Bypass valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
Discharge device . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-14
Hydraulic fan drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-17

Hydraulic truck diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18

Overview and explanations of diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-18
Hydrostatic travel drive - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-20
Hydraulic motor HMF 135 -02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-24
HPV 105 -02 pressures - tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-26

3 Chassis
Chassis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Axle suspension . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1

4 Undercarriage
Steering system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1
Steering system - functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1

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Table of contents

Brake system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4

Brake release valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4
Brake cables - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6
Brake valves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-10
Brake system - check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-13

6 Electrical system/electronic system

Central electrical system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-1
Arrangement of the interface connectors console - truck . . . . . . . . . . . . . . . . . . . . 6-1
Layout of relays and fuses for standard and optional equipment . . . . . . . . . . . . . . . 6-2
Composite instrument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-4
Positions of the working lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-8

7 Hydraulics
Working hydraulics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Functional description of control valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
Circuit diagram of working hydraulics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-6
Hose layout pump - control valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8
Hose layout control pressure supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
Hose layout for lifting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-10
Hose layout for tilting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
Hose layout return flow to oil reservoir . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-12
Hose layout in auxiliary hydraulics for standard mast . . . . . . . . . . . . . . . . . . . . . . 7-13
Hose layout in auxiliary hydraulics for duplex and triplex mast . . . . . . . . . . . . . . . 7-14

8 Loading system
Mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Mast - identification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
Mast - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
A dusting the lift chain (all series) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-2
Adjustment of roller clearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Roller clearance - fork carriage in inner mast, type 189 . . . . . . . . . . . . . . . . . . . . . . 8-4
Roller clearance - middle and inner mast, type 189 . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Outer Mast Roller Clearance, Type 189 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Removal of slide pads - standard mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-6
Removal of slide pads - duplex mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-8
Removal of slide pads - triplex mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-10
Lift cylinder (outer) - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-13

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Table of contents

Lift cylinder (centre) - removal and installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-14

Lift cylinder - sealing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-16
Tilt angle sensor - adjustment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-17
Tilt cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-20
Hose reel - removal, hose change, sealing, installation . . . . . . . . . . . . . . . . . . . . . 8-30

Annex

9 Circuit diagrams
Hydraulic circuit diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1
Hydraulic wiring diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-1

Electrical circuit diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-2

Circuit Diagram Standard Equipment, LPG Engine, Sheet 1 . . . . . . . . . . . . . . . . . . . 9-3
Circuit Diagram Standard Equipment, LPG Engine, Sheet 2 . . . . . . . . . . . . . . . . . . . 9-5
Circuit Diagram Standard Equipment LPG Engine, Sheet 3 . . . . . . . . . . . . . . . . . . . 9-7
Circuit Diagram Standard Equipment Diesel Engine, Sheet 1 . . . . . . . . . . . . . . . . . 9-9
Circuit Diagram Standard Equipment Diesel Engine, Sh. 2 . . . . . . . . . . . . . . . . . . 9-11
Circuit Diagram Standard Equipment Diesel Engine, Sheet 3 . . . . . . . . . . . . . . . . 9-13
Wiring diagram for optional lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-15
Wiring diagram for options, lighting higher . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-17
Wiring diagram for optional equipment, truck data management . . . . . . . . . . . . . 9-19
Wiring diagram for optional heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-21
Wiring diagram for optional soot filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-23
Circuit diagram for optional wipers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-25

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The BR 394 diesel truck

The truck series 394 H 40 - H 50

Power is redefined with the new generation of prevents dust and foreign particles from penetra-
fork trucks H 40, H 45 and H 50 for very heavy ting the assemblies. The engine bonnet can be
duty: Unequalled operating comfort increases opened wide, additional access covers make the
productivity, which, together with fuel economy fast servicing easier.
and low service costs, translates into superior
economy. Engine

Design of operator’s compartment The low-noise diesel engines convince with their
state-of-the-art engine technology: high torque,
The operator’s compartment, developed accor- fuel economy, low exhaust emissions (NOx, CO,
ding to the ergonomic findings, has an automo- HC), low soot emissions.
bile-type quality, options like radio, heating and
air conditioning are perfectly integrated in the ca- Drive
bin, numerous places to put things complete the
picture. The indicators and switches installed in No clutch, no transmission, no brake: The step-
the canopy console of the truck are easily acces- less Linde hydrostatic drive excels especially in
sible. All mast functions can be operated sensi- extreme applications due to its low-wear techno-
tively with the Linde Load Control; the two levers logy.
integrated in the arm rest respond to the sligh-
test movement of the finger. Also fatigue-free Electronic / electrical system
is the Linde dual-pedal control for fast reversing
The Linde Truck Control (LTC) adjusts the engine
without shifting the feet; annoying road bumps
speed intelligently to the particular demand of the
are damped by the rubber-mounted drive axle. A
hydraulic system and can be adapted individually
low driving noise relieves the operator and envi-
to any task. All safety-related truck components
ronment and ensures, together with an excellent
such as microprocessors exist twice; a selft-test
panorama view, the high safety standards.
makes servicing easier. The protection of the
control unit and electric cables against moisture
Chassis and dirt complies with the highest automotive
The unit of overhead guard and chassis (Linde standard and also increases functional reliability.
ProtectorFrame) guarantees the greatest pos-
sible stability and protection. The closed chassis

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0 Product information
The BR 394 diesel truck

Steering • The line safety valve prevents that the fork

carriage drops uncontrolled with the load if a
The hydrostatic steering responds without nearly lifting hydraulics supply line is damaged.
any play. The ergonomic steering wheel with
• Duo-sensitive safety belt.
adjustable tilt angle fits easily and precisely in the
driver’s hands. Good driving characteristics in curves and pre-
cise steering are naturally characteristic of this
Mast series.

Overhead tilt cylinders allow the full load capa- Standard equipment
city and a high residual capacity even at high
lift heights. Slim mast channels ensure unobst- • Hydraulically cushioned full suspension seat
ructed view on the load and environment, main- with a comprehensive range of settings.
tenance-free rubber-mounted coupling points • The Linde double pedal control for all driving
dampen impacts and vibrations and the electro- motions and the Linde Load Control for relaxed
nic limitation of the tilt angle bring the mast gently and precise operation of all mast functions.
and quietly in the end position.
• Air filter with integrated cyclone separator
Brake • High-performance hydraulic filter concept for
maximum purity of the oil and the optimum
Three independent brake systems ensure grea- service life of all hydraulic components.
test possible safety: • Anti-glare display with indicators, for example,
• Gentle hydrostatic braking as soon as the for fuel level, time, operating hours, service
accelerator is released means wear-free information and indicator lights for all important
deceleration in everyday operation. truck functions.
• Emergency braking by depressing the brake • Various places to put things for writing utensils,
pedal (hydrostatic braking and added dece- beverage cans, etc.
leration by maintenance-free multiple disc • SE tyres.
brake. • Standard mast, lift h3 = 3100/3000 mm (H 40,
• Automatic application of the parking brake H 45 / H 50).
when the engine of the vehicle is shut off. • Forks, I = 1000 mm.
• Fork carriage width b3 = 1350 mm.
Safety is our prime concern
Particular highlights are: Options
• Excellent ergonomics freeing the operator • Single-pedal model with directional switch in
of all unnecessary tedious tasks so that the the arm rest.
operator can work nearly fatigue-free. • Standard masts with lifting heights ranging
• The hydrostatic drive brakes automatically from 3000 to 5400 mm.
when the accelerator pedal is released. • Duplex masts (full free lift) with lifting heights
• The noise level is very low, signals from the ranging from 3030 to 4130 mm.
surroundings can be heard well. • Triplex masts (full free lift) with lifting heights
• All safety-related truck components exist twice ranging from 4525 to 6315 mm.
(redundant) for highest functional safety. • Load screen.
• High degree of safety and stability due to the • Single and double auxiliary hydraulics for all
Linde ProtectorFrame. mast types.
• Superb visibility through the mast, excellent • Single-lever operation of the lifting hydraulics.
overall visibility and visibility upwards through
• Various fork lengths.
the overhead guard.
• Overhead guard can be extended as far as the
• Full load capacity up to high lift heights and
operator’s compartment with roof, front and
high residual capacity.
rear windscreens and doors (also with tainted
panes).
• Wiper-wash system for front, rear and roof
windscreens.

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The BR 394 diesel truck

• Seats with improved comfort (lordotic support, • Road kit.

seat heater) and adjustment settings. • Integrated soot filter for diesel.
• Warm water heating with integrated pollen • Dust ejector.
filter.
• Acoustic alarm when reversing, omnidirectio-
• Air conditioning with integrated pollen filter. nal strobe and turn signal lights.
• Radio with cassette deck and loudspeakers. • Volumetric filling with low-fuel level warning in
• Roof blind, clipboard, interior lighting, steering the display.
column also height-adjustable. • Bio diesel fuel (RME) capability.
• Truck lighting, working lights. • Custom painting
• Mirror.

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0 Product information
Diagnosis

LTC - basic structure

1 Joysticks 6 Internal combustion engine

2 Display 7 Pedal group
3 Mast 8 Directional control switch
4 Directional control valve block 9 Integrated traction/lift control
5 Traction pump

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Diagnosis

System communication - overview and

position of modules

1 VW module
2 LTC module
3 CAN bus (communication)
4 Display

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Diagnosis

LTC modules - difference between diesel and LPG trucks

1 LP gas, no engine diagnosis 7 VW diagnosis (ISO)

2 LPG shut-off valve 8 engine control
3 Ignition control unit 9 Injection system
4 Internal combustion engine 10 Internal combustion engine
5 Diesel, with engine diagnosis 11 Immobilizer
6 CAN bus

Engine electronics - overview

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Diagnosis

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0 Product information
Diagnosis

1 Joysticks 12 Engine speed sensor

2 Display 13 Engine control unit
3 CAN bus I 14 VW diagnosis
4 CAN diagnostic connector 15 CAN bus II
5 Tilt angle sensor mast 16 Fan
6 Mast 17 Immobilizer
7 Traction pump 18 Fuel shut-off valve
8 Directional control valve block 19 Pedal group
9 Pump control 20 Directional control switch
10 Internal combustion engine 21 Integrated traction/lift control LTC module
11 Injection system

LTC - system overview

1 Display 5 Immobilizer
2 CAN bus I 6 VW engine control unit
3 CAN diagnostic connector 7 CAN bus II
4 VW diagnosis (ISO) 8 Integrated traction/lift control LTC module

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Diagnosis

Composite instrument - fault codes

The error codes are shown in the text field (1)
(2x11 characters) and in case an “optional soot
filter” is fitted, its residual capacity.
The sequence in which the error codes are shown
depends on the one hand on the code letter (T
before L before D... error) and on the other hand
from the sequence in which the error numbers
are transmitted on the CAN. If more faults have
occurred than can be shown, the list must be
scrolled with the button.
In the event of characters “<” in the text field scroll
with the left button to the left and in the event of
characters “>” in the text field scroll with the right
button to the right.
Priority of error code display: T before L before D
before F before R before X before Y before Z 1 Text field

T Traction
L Lift
D Display
F Soot filter
R Recorder (data logger)
X, Y, Z CSM 1 to 3

An engine fault message is indicated by a flas-

hing of the preheating indicator.

NOTE

Error codes and possible remedial action are

outputted and evaluated via the diagnostic pro-
gram“Pathfinder”.

LTC traction control codes, release 1.0.0

Conditions
Error accelerator potentiometer zero position or 5 V potentiometer supply fault after
1
ignition ON
2 Accelerator potentiometer in zero position
3 Brake pedal not yet actuated after ignition ON
4 Seat not occupied
5 Speed restriction active
6 Directional control switch in zero position (single-pedal model)
8 Brake pedal depressed half way
9 Brake pedal depressed fully
10 Intervention by working hydraulics requested
11 Control unit in programming mode

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0 Product information
Diagnosis

13 Safety relay: Voltage under 8 V

14 Terminal 15: Voltage under 8 V
16 Intervention by data logger requested
17 Intervention by soot filter requested
18 Door not closed (only in trucks with door switch)
19 Teaching of accelerator potentiometer not yet performed

Warnings
Signals of seat switch and accelerator potentiometer not plausible for more than 2 se-
104
conds
124 Seat switch signals overlapping for more than 5 s
130 Coolant temperature sending unit: Signal outside of valid range
134 Hydraulic oil sensor: Signal outside of valid range
150 Throttle plate solenoid: Current too low (LPG trucks only)
157 Fan bypass valve: Current too high
158 Fan bypass valve: Current too low
159 Throttle plate solenoid: Current too high (LPG trucks only)
160 Throttle plate solenoid never activated (LPG trucks only)
167 Power stage of fan bypass valve always activated
168 Power stage of fan bypass valve never activated
169 Throttle plate solenoid always activated (LPG trucks only)
175 Fault in throttle plate solenoid circuit (LPG trucks only)
179 Fault in the fan bypass valve circuit
180 No data from safety processor

Problem
220 Invalid truck type
221 Production test not OK
222 EEPROM error
Directional control switch: Direction signal overlaps zero setting signal for more than
225
10 s
The switch-controlled speed limitation function is activated and the corresponding sig-
226
nals of the switch (change-over contact) are not compatible.
Accelerator: Signals of reference potentiometer and watchdog potentiometer not plau-
231
sible
232 Accelerator: Reference potentiometer cable breakage or short
233 Accelerator: Reference potentiometer cable breakage or short
235 Directional control switch: Signals not plausible
236 Directional control switch: All inputs open (eg coded connector missing)
237 Brake: Semi-actuation signals not compatible
238 Brake: Normally closed contact switch 1 and switch 2 not plausible
239 Seat switch: Signals not plausible
240 Power stage of LPG shut-off valve never activated (LPG trucks only)
241 5V supply voltage for sensor too low
243 Safety relay does not close
244 Safety relay does not open

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Diagnosis

245 Power stage release: Activation and feedback not plausible

246 Power stage of release valve never activated
247 Release valve: Current too low
248 Speed sensing fault
249 LPG shut-off valve: Current too low (LPG trucks only)
250 Throttle plate solenoid: Current too low (LPG trucks only)
251 Brake valve: Current too high (only for trucks with retarder brake)
252 Brake valve: Current too low (only for trucks with retarder brake)
253 Pump forward: Current too high
254 Pump forward: Current too low
255 Pump reverse: Current too high
256 Pump reverse: Current too low
259 Throttle plate solenoid: Current too high (LPG trucks only)
260 Throttle plate solenoid never activated (LPG trucks only)
261 Power stage of brake valve always activated (trucks with brake valve only)
262 Power stage of brake valve never activated (trucks with brake valve only)
263 Power stage for pump forward always activated
264 Power stage for pump forward never activated
265 Power stage for pump reverse always activated
266 Power stage for pump reverse never activated
269 Throttle plate solenoid always activated (LPG trucks only)
270 Safety processor detects deviating signal from speed sensor
271 Safety processor detects deviating value to 5V supply voltage
272 Safety processor detects deviating signal from truck accelerator potentiometer
273 Safety processor detects deviating signal current pump forward
274 Safety processor detects signals deviating from directional control switch
275 Fault in throttle plate solenoid circuit (LPG trucks only)
276 Fault in brake valve circuit (trucks with retarder brake only)
277 Fault in pump forward circuit
278 Fault in pump reverse circuit
340 Power stage of LPG shut-off valve always activated (LPG trucks only)
345 Release valve: Maximum current exceeded
346 Power stage of release valve always activated
347 Release valve: Current too high
348 Gas shut-off valve: Maximum current exceeded (LPG trucks only)
349 LPG shut-off valve: Current too high (LPG trucks only)
350 Throttle plate solenoid: Current zero with power stage activated (LPG trucks only)
352 Brake valve: Current zero with power stage activated (only for trucks with retarder brake)
354 Pump forward: Current zero with power stage activated
356 Pump reverse: Current zero with power stage activated
Safety processor detects deviating feedback signal at PWM power stages for IC engine
370
actuators
Safety processor detects deviating feedback signal at PWM power stage for hydrostatic
371
actuators
372 Safety processor detects deviating signal at operator inputs

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0 Product information
Diagnosis

373 Safety processor detects deviating signal for pump reverse current
374 Safety processor detects deviating signal pedal coding
380 No data from safety processor
481 Safety processor: truck speed too high
482 Safety processor: truck speed too low
Safety processor: pump control in forward direction not plausible in relation to accelera-
483
tor potentiometer
Safety processor: pump control in reverse direction not plausible in relation to accelera-
484
tor potentiometer
484 Safety processor: Activation of pump reverse not plausible to accelerator potentiometer
488 Safety processor: LPG shut-off valve activated at speed 0 (LPG trucks only)
490 Safety processor: Switch-off test fault

LTC - Lift Control Codes, Version 1.0.0

States
1 Power On, procedure not completed
2 Joystick neutral
3 Tilting at the stop, end position damping active or programmed position reached
4 Programmed end position exceeded
5 Invalid truck type
7 Door not closed (only on trucks with door switch)
11 Control unit in programming mode
12 Safety processor not active
14 Terminal 15: Voltage under 8 V
15 EEPROM fault
16 Mast positioning active
17 Seat switch not actuated
18 not
19 No teaching of joysticks
20 Switching from 2nd to 3rd auxiliary hydraulics results in implausible signals briefly

Warnings
141 Incompatibility between signal/reference signal seat switch
146 Seat switch: Seat not occupied for more than 2 seconds
180 No data from safety processor

Faults
220 Tilt sensor cable breakage
221 Reference potentiometer tilt sensor incompatible
222 Joystick not in neutral position for more than 2 sec after Power On
230 Cable breakage joystick lifting/lowering
231 Cable breakage joystick tilting
232 Cable breakage joystick AUX1
233 Cable breakage joystick AUX1
235 Incompatibility between signal/reference potentiometer lifting/lowering

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 Product information 0
Diagnosis

236 Incompatibility between signal/reference potentiometer tilting

237 Incompatibility between signal/reference potentiometer AUX1
238 Incompatibility between signal/reference potentiometer Aux2
239 Incompatibility between signal/reference signal seat switch
247 Switching from 2nd to 3rd auxiliary hydraulics constantly results in implausible signals
250 Monitoring PWM (pulse width modulation) lifting/lowering
251 Monitoring PWM tilting
252 Monitoring PWM AUX1
253 Monitoring PWM AUX2
254 Solenoid current lifting/lowering too low
255 Solenoid current tilting too low
256 Solenoid current AUX1 too low
257 Solenoid current AUX2 too low
258 Solenoid current lifting/lowering too high
259 Solenoid current tilting too high
260 Solenoid current AUX1 too high
261 Solenoid current AUX2 too high
262 Voltage at lifting solenoid permanently high
263 Voltage at lowering solenoid permanently high
264 Voltage at forward tilting solenoid permanently high
265 Voltage at backward tilting solenoid permanently high
266 Voltage at solenoid AUX1+ permanently high
267 Voltage at solenoid AUX1- permanently high
268 Voltage at solenoid AUX2+ permanently high
269 Voltage at solenoid AUX2- permanently high
270 Voltage at lifting solenoid permanently low
271 Voltage at lowering solenoid permanently low
272 Voltage at forward tilting solenoid permanently low
273 Voltage at backward tilting solenoid permanently low
274 Voltage at solenoid AUX1+ permanently low
275 Voltage at solenoid AUX1- permanently low
276 Voltage at solenoid AUX 2+ permanently low
277 Voltage at solenoid AUX 2- permanently low
280 Safety relay always Off
281 Safety relay always Off after Power On
282 Safety relay always On
283 Safety relay always On after Power On
284 Lowering release valve current too low although activated
285 Lowering release valve current too high although not activated
286 Lowering release valve current very high
287 Lowering release valve always OFF
288 Lowering release valve always ON
289 Safety valve current low although activated
290 Lowering release valve current too high although not activated
291 Lowering release valve current very high

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0 Product information
Diagnosis

292 Safety valve always OFF

293 Safety valve always ON
294 5V power supply too low
295 Production test not OK
350 Safety processor detects deviating lifting/lowering joystick signal
351 Safety processor detects deviating tilting joystick signal
352 Safety processor detects deviating joystick AUX 1 signal
353 Safety processor detects deviating joystick AUX 2 signal
354 Safety processor detects deviating PWM of lifting/lowering joystick
355 Safety processor detects deviating tilting PWM
356 Safety processor detects deviating AUX 1 PWM
357 Safety processor detects deviating AUX 2 PWM
358 No teaching of tilt angle limit stops in safety processor
359 Safety processor detects deviating tilt angle signal
380 No data from safety processor
410 Safety processor: Lifting, PWM high though joystick signal low
411 Safety processor: Lowering, PWM high although joystick signal low
412 Safety processor: Forward tilt, PWM high though joystick signal low
413 Safety processor: Backward tilt, PWM high though joystick signal low
414 Safety processor: AUX1+, PWM high though joystick signal low
415 Safety processor: AUX1-, PWM high though joystick signal low
416 Safety processor: AUX1+, PWM high though joystick signal low
417 Safety processor: AUX2-, PWM high though joystick signal low
418 Safety processor: Safety valve switch-off test unsuccessful
419 Safety processor: Safety relay switch-off test unsuccessful
420 Safety processor: Lowering release valve switch-off test unsuccessful
421 Safety processor: Internal signals PWM lifting/lowering incompatible
422 Safety processor: Internal signals PWM tilting incompatible
423 Safety processor: Internal signals PWM AUX1 incompatible
424 Safety processor: Internal signals PWM AUX2 incompatible
425 Safety processor: Internal PWM signals error
426 Safety processor: Forward tilt driven although mast outside of the front electric stops
Safety processor: Backward tilt controlled although mast outside of the behind electric
427
stops

LTC codes of composite instrument

Warnings
152 General fault of composite instrument
154 Composite instrument CAN interface over 200 ms in the bus-off condition
156 Traction control / heartbeat message missing for over 400 ms
158 Lift control / heartbeat message missing for over 400 ms
160 Soot filter control / heartbeat message missing for over 400 ms
162 Data logger / heartbeat message missing for over 400 ms
164 CSM 2 CAN / heartbeat message missing for over 400 ms

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 Product information 0
Diagnosis

166 CSM 2 CAN / heartbeat message missing for over 400 ms

168 CSM 3 CAN / heartbeat message missing for over 400 ms
182 Display button pressed for over 120 s
184 Oil pressure control signal shorted to earth and engine speed < 10 rpm.
UD alternator < 8.2 V for t > 300 ms and engine speed > 900 rpm or if battery charging
186
warning light signal OFF and engine speed < 10 rpm.
188 Air filter restricted signal shorted to earth and engine speed < 10 rpm
Signal of differential pressure of hydraulic system oil micro-filter shorted to earth and
190
engine speed < 10 rpm
192 Selected characteristic does not match the signals of the fuel level sending unit

Service Training – 394 804 2401 EN – 01/2005 0-15

0 Product information
Diagnosis

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Description of transmission
Technical data for BMF VR6
type of engine Engine type VW BMF (with Impco LPG system)
Number of cylinders 6 in V-type arrangement 15°
Cubic capacity 3189 cm3
Power 55 kW at 3200 rpm
Compression ratio 11.25 : 1
Desired pressure = 10 - 13 bar
Compression
Wear limit 7.5 bar
Maximum admissible pressure difference 3 bar
Lower idle speed 1000+50 rpm
Upper idle speed during travel 2700 rpm
Upper idle speed during lifting 2800 rpm
Rated speed 1900 rpm at Md = 225 Nm
Speed limitation 3050 rpm
Valve clearance hydraulically self-adjusting, 4 valves per cylinder
with maintenance-free chain und two adjustable
Valve drive camshafts, with roller-type finger at intake and
exhaust
Ignition Electronic firing order
firing point 20° BTDC at 1000 rpm
Firing order 1-5-3-6-2-4
Lubricating oil pressure at 1000 rpm and an oil
> 1.7 bar at 1500 rpm
temperature of 80°C
Lubricating oil pressure at 2000 rpm min 3 - 4.5 bar
Oil pressure switch Switching range at 0.85 - 0.55 bar
Cylinder 1 Opposite power takeoff side
NGK 12 KR 7B, VW No. 101905606 A
spark plugs at maintenance interval of 1000 hours Spark plug gap 0.85 mm
Tightening torque: 20 Nm
approx. 6.6 litres in total
Engine oil quantity
Oil change quantity approx. 6 litres
start of opening: 80 °C
Thermostat
fully open at 105 °C
Vaporiser: Cobra
Impco LPG system Mixer: CA 100
Solenoid shut-off valve with filter

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Engine block
Ribbed V-belt - installation and
removal

Ribbed V-belt
¾ Remove the engine cover.
¾ Mark the running direction of the ribbed V-belt.

Right-hand side in direction of travel

1 Spring-loaded idler pulley
2 Alternator
3 Air conditioning
4 Crankshaft
5 Water pump
6 Ribbed V-belt

¾ Screw the M8 x 50 screw into the threaded

hole -arrow- of the spring-loaded idler pulley
until the tension of the ribbed V-belt is relieved.
¾ Remove the ribbed V-belt.

Ribbed V-belt - installation

¾ Check the alternator, A/C compressor and
vane pump for security.
¾ Check the reflection pulley for ease of move-
ment.

NOTE
When installing the V-ribbed belt, please make
sure the belt is installed in the correct running
direction.

¾ Install the ribbed V-belt and screw the M8

screw out of the spring-loaded idler pulley
again.
¾ Check that the belt is properly positioned in the
pulleys.

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Compression - test
Required special tools
• Spark plug spanner 3122 B
• Puller T10095 A
• Mounting tool T10118
• Torque spanner 5 - 50 Nm
• Compression tester VAG 1763

Prerequisites for testing

• Engine oil temperature at least 30 °C.
• The battery voltage must be at least 11.5 V.
• All electrical loads such as rear window hea-
ting must be switched off.
• The air conditioning system of the truck, if fit-
ted, must be switched off.

Test procedure
¾ Start the engine and remove the plug from the
gas supply shut-off valve.
¾ Pull the connectors from the ignition coils 1 - 6.
Use the mounting tool T10118 to unlock the
connector catches.
¾ Install the mounting tool T10118 to the catch
button (arrow) and carefully remove the con-
nector.
¾ Slide the puller T10095 A on from the straight
side of the connector in the arrowed direction
and pull the ignition coil and power stage out.
¾ Remove the spark plugs with the spark plug
spanner 3122 B.
¾ Have a second engineer depress the accele-
rator fully.
¾ Check the compression with the compression
tester VAG 1763.

NOTE

Use the tester as described in the operating in-

structions supplied with the tester.

¾ Actuate the starter until the tester no longer

indicates a rise in pressure.

Compression readings
New: 10 - 13 bar
Wear limit: 7.5 bar

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Admissible difference between all cylinders:

3 bar
¾ Install the spark plugs with the spark plug
spanner 3122 B and torque to 20 Nm.
¾ Install the ignition coils with power stages.

Cylinder head - removal and installation

1 Cylinder head cover 4 Bracket

2 Torque: 10 Nm 5 Torque: 10 Nm
3 O-ring 6 Oil filler cap

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 Engine 1
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7 Oil filler neck 24 Torque: 8 Nm

8 Body-bound rivet 25 Sealing ring
9 Torque: 10 Nm 26 Bracket
10 Distance sleeve and sealing ring 27 Coolant thermostat, housing
11 Torque: 23 Nm 28 Sealing ring
12 Bracket for knock sensor connector 29 Hall sensor
13 Lift bracket 30 Cover
14 Camshaft chain 31 Bracket
15 Valve for camshaft adjuster, intake 32 Torque: 60 Nm
16 Valve for camshaft adjuster, exhaust 33 Exhaust camshaft positioner
17 Bracket for cable loom 34 Bracket for camshaft chain
18 O-ring for oil passage sealing 35 Intake camshaft adjuster
19 Hall sensor 36 Cylinder head gasket
20 Cain tensioner, torque 40 Nm 37 Cylinder head
21 Sealing ring 38 Tensioner
22 Torque: 10 Nm 39 Cylinder head bolt
23 Bracket for cable loom and earth lead 40 Gasket for cylinder head cover

Check the cylinder head for flatness

Required gauges and test equipment
• Ruler
• Feeler gauge
Maximum permissible distortion: 0.05 mm

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Cylinder block - removal and installation

Required special tools
• Camshaft setting jig T10068 A
• Torque spanner 5 - 50 Nm
• Torque spanner 40 - 200 Nm
• Hose clamp pliers VAS 5024 A
• Puller T10095 A
• Polydrive key 3452
• Oil pan
• Sealant AMV 174 004 01
• Sealant AMV 176 501

Cylinder block - removal

WARNING

When opening the expansion reservoir, hot

steam or hot coolant can emerge and cause
severe scalding.
Cover the filler cap with a cloth and open it care-
fully.

¾ Open the expansion reservoir filler cap and

refit it to reduce the pressure in the cooling
system.
¾ Drain the coolant.
¾ Remove the coolant expansion reservoir.
¾ Remove the coolant thermostat housing.

NOTE

Before disconnecting the plugs, mark them to

identify their assignment to a component.

¾ Disconnect the plug from the following compo-

nents.
• Coolant temperature sending unit.
• Pump for continued coolant circulation.
• Injection valve for cylinders 1 to 6

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¾ Disconnect the connectors from Hall sensor

(1) (G40) and Hall sensor (2) (G163).
¾ Disconnect the connectors from valve 1 for
camshaft adjuster, intake (3) and from valve 1
camshaft adjuster, exhaust (4).
¾ Disconnect and place aside all other electric
cables from the cylinder head.
¾ Disconnect all connecting leads, coolant and
vacuum hoses from the cylinder head.
¾ Remove the ribbed V-belt.

¾ Turn the crankshaft in the direction of engine

rotation to the TDC mark of cylinder 1 at the fa-
stening screw of the vibration damper (arrow).
¾ Remove the cylinder head cover.

¾ Remove the camshaft chain tensioner (arrow).

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¾ Remove the fastening bolts (arrows) from the

cover and take the cover off.

¾ Mark the camshaft chainbefore removal (eg

with paint, arrow in running direction).
¾ First remove the exhaust camshaft adjuster.

¾ Remove the camshaft adjuster together with

the camshaft chain from the intake camshaft.

NOTE

Hold the camshaft in place only with a 32 mm

open-end spanner ( arrow). The camshaft setting
jig T10068 A should not be installed when tighte-
ning and loosening the camshaft adjuster.

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 Engine 1
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¾ Remove the fastening bolts (arrows) and take

the chain guide (1) out.
¾ Put the camshaft chain aside.

¾ Loosen the cylinder head bolts in the given

sequence from the outside to the inside and
remove them.

NOTE
Use key 3452 for polydrive cylinder head bolts.

¾ Carefully remove the cylinder head with the

help of a second mechanic.
¾ Put clean cloths into the cylinders to prevent
dirt and abrasive residues from getting bet-
ween the cylinder face and piston.
¾ Also prevent dirt and abrasive residues from
getting into the coolant.
¾ Carefully clean the mating faces of cylinder
head and cylinder block. Take care not to
cause any long scoring or scratches (if emery
paper is used, the grain should not be less than
100).
¾ Check the cylinder head for flatness.

Cylinder head - installation

NOTE

A LPG system from Impco is mounted at the en-

gine inlet. That is why the cylinder head does not
have any threads for the installation of the injec-
tion nozzles and can therefore not be replaced
with a cylinder head from a car.
• When a replacement cylinder head is to be in-
stalled, first oil all mating faces of support ele-
ments, roller finger pivots and the cam faces of

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the camshafts before fitting the cylinder head

cover.
• The plastic caps supplied for the protection of
the open valves should not be removed until
just before the installation of the cylinder head.
• When the cylinder head is replaced, the entire
coolant must be renewed.

¾ Carefully remove emery and grinding residues

and the cloths.
When the piston of cylinder 1 is not in the TDC
position:
¾ Turn the crankshaft in the direction of engine
rotation to the TDC mark of cylinder 1 at the fa-
stening screw of the vibration damper (arrow).
Simultaneously have a second mechanic ad-
vance the camshaft chain by hand.

NOTE

Do not take the new cylinder head gasket out of

its packing until it is actually mounted. Handle the
new gasket with utmost care. Damage will lead
to leakage.

¾ Position the new cylinder head gasket. The

lettering (part number) must be legible.
¾ Be sure that the studs in the stud holes 12 and
20 are installed and the cylinder head gasket
is fixed in place.
¾ Set the camshafts in the cylinder head to TDC
of cylinder 1.

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 Engine 1
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¾ The camshaft setting jig T10068 A must fit in

both shaft grooves.
¾ Prepare the cylinder head gasket for installa-
tion.

NOTE

The longer cylinder head bolts are screwed into

the centre holes in the cylinder head.

¾ Put the cylinder head in place, insert the new

cylinder head bolts and tighten them by hand.

¾ Tighten the cylinder head bolts in the se-

quence shown in the illustration as follows:
¾ First tighten all bolts to a torque of 30 Nm.
¾ Then tighten all bolts to a torque of 50 Nm.
¾ Subsequently turn all bolts a 1/4 turn (90°) with
a normal spanner.
¾ Finally turn all bolts again by a further 1/4 turn
(90°).
The rest of the installation is done in the reverse
order of removal.

NOTE

Be sure that the O-ring for sealing the oil passage

and the sealing ring are fitted in the cover.

¾ Install the cylinder head cover and suction

tube.

Engine valve timing BMF - check and

adjustment
Check valve timing
Required test aid:
• Camshaft setting jig T10068 A
¾ Remove the suction tube and cylinder head
cover.
¾ Remove the engine undershield.

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¾ Set the crankshaft at the fastening bolt of the

shock absorber to the TDC mark for cylinder
1 (arrow) by turning it in the sense of engine
rotation.

¾ The camshaft setting jig T10068 A must fit in

both shaft grooves.
If the camshaft setting jig can not be inserted:
¾ Turn the crankshaft once in the sense of rota-
tion of the engine.

NOTE
If the camshaft setting jig can still not be inserted,
turn the crankshaft in the engine’s sense of rota-
tion to about 5 mm after TDC of cylinder 1 (due to
tolerances of the drive chains).

¾ Check if the timing marks on the camshaft

adjuster are in line with the marks on the valve
gear casing:
marks (A) and (B) on the camshaft adjusters must
be in line with the notches (arrow) on the valve
gear casing (C).
The distance between tooth X (1) and tooth (2) on
the camshaft adjuster must be exactly 16 rollers
of the camshaft chain.

NOTE

The drawing shows the view with the cover remo-

ved.

If the timing marks are not in line:

¾ Adjust valve timing.
If the timing marks are in line:
¾ Install the cylinder head cover and suction
tube.

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 Engine 1
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Valve timing adjustment

NOTE
The chains can only be installed when the engine
is removed.

Required special tools and aids:

• Camshaft setting jig T10068 A
• Holding jig T10069
• Torque spanner 5 - 50 Nm
• Torque spanner 40 - 200 Nm
• Sealant AMV 004 01 01
• Sealant AMV 176 501

NOTE
The following procedure is described with the en-
gine removed. Depending on how far the engine
is disassembled, the adjustment can begin at the
appropriate spot. The oil sump is removed und
may only be installed after the sealing flange is
mounted.

Install the camshaft chain und chain tensioner

with turnbuckle for intermediate shaft drive:
¾ Adjust the position of the crankshaft to the
intermediate shaft.
For this the ground tooth of the drive spro-
cket (B) must be aligned with the bearing joint
(TDC cyl. 1).
¾ Install the two pins without collar for slide rail
(2) and tighten to 10 Nm.

NOTE
• In case the camshaft chain has already run,
observe the running direction mark.
• All fastening screws for the sprockets must be
replaced.

¾ Slide rail.(2) with chain (1) and both sprockets

(3) und (4).
marking at the sprocket (4) for camshaft chain
must be aligned with the notch (C) or (D) on the
intermediate shaft thrust washer.
The chain must run fully straight in the slide rail
from the crankshaft to the intermediate shaft.
¾ Screw the sprockets (3) and (4) to the interme-
diate shaft by hand.

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¾ Release the ratchet in the chain tensioner (A)

on the opposite side with a small screwdriver
and press the tensioning rail against the chain
tensioner.
¾ Install the tensioning rail and tighten to 8 Nm.
¾ Hold the vibration damperin position with hol-
ding jig T10069.

¾ Tighten the new fastening screw of sprockets

(3) und (4) for the intermediate shaft to 60 Nm
+ ¼ turn (90°).
¾ Remove the holding jig T10069.
¾ Recheck the position of the crankshaft (B) to
the intermediate shaft (C) or (D).
¾ Return the engine to TDC of cylinder 1.
Install the camshaft chain:
¾ Set the built-in camshafts in the cylinder head
to TDC of cylinder 1.

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 Engine 1
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¾ If needed, turn the camshafts (arrow) to the

correct position with a 32 mm open-end span-
ner. The camshaft setting jig T10068 A should
not be inserted.

¾ Now it should be possible to insert the cams-

haft setting jig T10068 A in both shaft grooves.
If the cylinder head is removed, install the cylinder
head and leave the camshaft setting jig T10068 A
inserted.
¾ Place the camshaft chain on the sprocket on
the intermediate shaft.
¾ Lead the chain between the tensioning rail and
the slide rail towards the valve gear casing.

¾ Screw on the camshaft adjuster of the intake

camshaft.

NOTE

Due to a setscrew (arrow), the two camshaft ad-

justers (marked: “24E” on the intake end and
“32A” on the exhaust end) can only be screwed to
the camshaft sprocket take-up in one position.

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¾ Turn the sensor wheel (1) on the intake cams-

haft adjuster clockwise against the stop (ar-
row) and screw the adjuster in this position to
the intake camshaft stable with the camshaft
chain installed.

¾ Make sure the camshaft chain contacts the

slide rail (1)“tightly” and does not “sag.”.
The “24E” mark (A) on the camshaft adjuster
must be in line with the notch (arrow) on the valve
gear casing (C).

¾ Count exactly 16 rollers on the camshaft chain

starting from the “24E” mark on the adjuster
to the right and mark this roller with a coloured
pen.

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¾ Turn the sensor wheel (1) on the exhaust

camshaft adjuster clockwise against the stop
(arrow) and hold the adjuster in this position
with the sensor wheel.

¾ Insert the thus positioned exhaust camshaft

adjuster with the marking “32A” in the camshaft
chain so that exactly 16 rollers as previously
counted are between the marks “24E” and
“32A” (1) and (2).
¾ Install the exhaust camshaft adjuster on the
exhaust camshaft and screw on by hand.
¾ Remove the camshaft setting jig T10068 A.
¾ Rotate the crankshaft twice in the sense of
rotation of the engine and check the engine
valve timing.

NOTE
When turning the crankshaft, the tensioning rail
instead of the chain tensioner must be pressed
by hand against the camshaft chain.
¾ Check this adjustment.
If the marks are not aligned:
¾ Repeat the valve timing adjustment.
If the marks are aligned:
¾ Hold the camshaft to be tightened with a 32 mm
open-end spanner (arrow).

NOTE

The camshaft setting jig T10068 A should not be

inserted.

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¾ Tighten new fastening screws (3) on the intake

and exhaust camshaft adjusters (4) and (2) to
60 Nm + ¼ turn (90°) (tighten can be done in
several steps).
¾ Install the sealing flange. To do this, clean the
sealing face of the sealing flange and coat with
sealant AMV 176 501.
¾ Insert the mounting jig T10122/2 in the sealing
ring.
¾ Slide the sealing ring over the mounting jig
T10122/2 on the crankshaft journal and the
slide the sealing flange further on the cylinder
block.

NOTE

Watch for the setscrews in the cylinder block.

¾ Tighten the fastening screws to a torque of

8 Nm.
¾ Remove the mounting jig T10122/2 from the
crankshaft journal.
¾ To do this, coat the sealing face with sealant
AMV 174 004 01.
¾ Coat the O-ring for sealing the oil passage with
oil and install with the sealing ring in the cover.
¾ Install the cover, install all fastening screws
and tighten them lightly.
¾ First tighten the M8 fastening screws to 23 Nm,
then the M6 fastening screws to 8 Nm.
¾ Install the chain tensioner for camshaft chain
installation and tighten to 40 Nm.
¾ Rotate the crankshaft twice in the sense of
rotation of the engine and check the engine
valve timing.
¾ Install the coolant control housing.
¾ Install the cylinder head cover and suction
tube.

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Cylinder head cover - removal and

installation
Required special tools
• Pliers for spring clamps VW VAS 5024 A
• Torque spanner 5 - 50 Nm
• Mounting tool T10118
• Puller T10095 A

Cylinder head cover - removal

¾ Disconnect the battery with the ignition swit-
ched off.
¾ All cable binders which were loosened or cut
open during removal must be attached at the
same place upon installation.
¾ Remove the engine cover.

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Cooling
Cooling system of BMF engine

1 Spring-loaded idler pulley 4 Crankshaft

2 Alternator 5 Water pump
3 Air conditioning 6 Ribbed V-belt

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 Engine 1
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Water pump after-running

1 Water pump for after-running

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Cooling system - hose routing

1 Restrictor Ø 3 mm, integrated in coolant expan- 5 Check valve

sion reservoir 6 Pump for continued coolant circulation
2 Expansion reservoir 7 Oil cooler
3 Radiator 8 Cylinder head
4 Heater 9 Vaporiser
4a If heater fitted, otherwise ports closed 10 Bleed screw

Only the coolant G 12 is allowed for the cooling

system of the engine type BMF. Please also refer
to “Coolant - draining and filling”
The engine type BMF has two water pumps.
The pump for continued coolant circulation pre-
vents the overheating of the coolant when the en-
gine is turned off. It starts delivering at a coolant
temperature of 95 °C and at under 90 °C it swit-
ches off again.

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 Engine 1
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NOTE
• When the engine is warm, the cooling system
is pressurised. If necessary, relieve any pres-
sure before doing repairs.
• Hose connections are secured with spring
clamps. In case of repair, only spring clamps
should be used.
• The mounting tool VAS 5024 or the pliers
VAG 1921 are recommended for fitting the
spring band clamps.
• Install coolant hoses without tension, avoi-
ding contact with other components (observe
marking on the coolant hose connection and
hose).

Coolant - draining and filling

Required special tools
• Pliers for spring clamps VW VAS 5024 A
• Antifreeze tester T10007

Coolant - draining

WARNING

When the expansion reservoir is opened, hot

steam may escape, causing severe scalding.
Cover the cap with a cloth and open it carefully!

¾ Open the sealing cap of the coolant expansion

reservoir.
¾ Use the pliers for spring band clamps
VW VAS 5024 to pull off the lower coolant
hose at the radiator.

NOTE
Please observe the regulations for discarding
coolant!

Coolant - filling

NOTE
• Only G 12 acc. to TL VW 774 D may be used
as coolant additive.Characteristic colour: lilac
• G 12 and coolant additives with the note “in ac-
cordance with TL VW 774 D” prevent damage
caused by frost and corrosion, lime deposits
and, moreover, raise the boiling temperature.
For these reasons, the cooling system should

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always be filled with antifreeze and anti-corro-

sion agent all the year round.
• Especially in countries with a tropical climate,
the coolant contributes, due its higher boiling
point, to operational reliability at high engine
loads.
• The antifreeze protection must be guaranteed
down to approx. -25 °C (in countries with Arctic
climate down to approx. -35 °C).
• Even during the warm season and in warm
countries, never reduce the concentration of
the coolant by adding water. The coolant addi-
tive portion should be at least 40%.
• If, for climatic reasons, a stronger frost pro-
tection is required, the amount of G 12 can be
increased, but only up to 60 % (frost protec-
tion down to approx. -40 °C), since this would
reduce the frost protection again and also the
cooling effect.
• If the radiator, heat exchanger, cylinder head
or cylinder head gasket were replaced, do not
reuse the coolant.
• To determine the current antifreeze concen-
tration, it is recommended to use the refracto-
meter T10007.

Recommended mixing ratio:

Percentage of
Frost protection to G 121 Water2
antifreeze
-25 °C 40 % 2.9 L 4.2 L
-35 °C 50 % 3.55 L 3.55 L

¾ Close the coolant drain plug.

¾ Fill in coolant up to the maximum mark on the
expansion reservoir.
¾ Close the expansion reservoir.
¾ Start the engine and increase engine speed to
approx. 2500 rpm for 3 minutes.
¾ Run the engine until the fan starts operating.

WARNING

When the expansion reservoir is opened, hot

steam may escape, causing severe scalding!
Cover the cap with a cloth and open it carefully.

¾ Check the coolant level, adding coolant if ne-

cessary.
1 The coolant quantity may vary depending on the truck equipment.
2 The coolant quantity may vary depending on the truck equipment.

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When the engine is at operating temperature, the

coolant level must be at the max mark; when the
engine is cold, it must be between the min and
max mark.

Coolant thermostat - housing disassembly and assembly

1 O-ring 6 Manifold
2 Clip 7 Gasket
3 Coolant thermostat housing 8 Coolant temperature sending unit
4 Screw, torque 8 Nm 9 Plug
5 Coolant thermostat

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Engine electrical system

Alternator
To exchange the three-phase alternator, the
freewheel pulley must be removed and installed
again.

Freewheel pulley - removal and installa-

tion
Required special tool
• Polygon head adapter 000 941 8015

Freewheel pulley - removal

¾ Remove the ribbed V-belt.
¾ Remove the protective cap on the freewheel
pulley.
¾ Put the hexagon socket (6 mm) on the drives-
haft of the three-phase alternator.

¾ Support the polygon head adapter

000 941 8015 17 with a ring spanner (17 mm)
and release freewheel pulley by turning
the driveshaft of the three-phase alternator
anticlockwise.

Freewheel pulley - Installing

¾ Insert the polygon head adapter 000 941 8015
in the freewheel pulley.
¾ Screw the freewheel pulley - at first manually
- against the stop onto the driveshaft of the
three-phase alternator.
¾ Support the polygon head adapter
000 941 8015 with a ring spanner (17 mm)
and tighten freewheel pulley by turning the
three-phase alternator anticlockwise with the
torque wrench.
Tightening torque: 80 Nm
¾ Refit the protective cap on freewheel pulley.
¾ Install the ribbed V-belt.

Terminal DFM on three-phase alternator

The signal at terminal DFM is only evaluated in
connection with the auxiliary heater. The signal
for free charging capacity is applied to alternator
terminal DFM.

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Self-test
Lack of plausibility or interruption are stored as
possible error causes.

Terminal DFM - additional signal

Contact 38 at controller 0N1
The DFM line connects the electronic control
unit 0N1 with the combined processor in which
the electronic immobilizer 0N2 (terminal W) is
integrated. The immobilizer signal is transmitted
over this cable. After each replacement of the
control unit the new code must be read into the
combined processor.

Self-test
The electronic control unit detects the interruption
of this line. The engine can no longer be started
in this case.

LPG installation
LPG installation - functions

1 LPG cylinder 2 Pressure reducing valve

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3 Fault light 12 Internal combustion engine

4 Electromagnetic shut-off valve with filter 13 Linde engine speed sensor for LTC
5 Coolant ventilation 14 Solenoid valve camshaft adjustment exhaust
6 Vaporiser / pressure regulator 15 LTC
7 Ignition lock 16 Phase sensor exhaust camshaft
8 Air filter 17 Phase sensor intake camshaft
9 Mixer 18 Solenoid valve camshaft adjustment intake
10 Throttle 19 VW engine speed sensor for ignition controller
11 Positioning magnet 20 Ignition controller

Vaporiser - operation Operation

The liquefied gas must be converted to a gaseous During operation, the throttle valve position is
state before it can mix with the air in the mixer to changed by the LTC traction controller (15), de-
produce an ignitable mixture. This conversion is pending on the speed and engine load. The
achieved with the vaporiser heated by the cooling resulting increase or reduction of the vacuum
water of the engine. controls the secondary diaphragm in the vapori-
ser, thus changing the gas flow and the mixture
Its operation is as follows:
ratio in the mixer (9).
The IMPCO vaporiser is a combined two-stage
When the vacuum increases due to a restricted
regulator with vaporiser. It receives the LP gas
air filter, this pressure counteracts the opening
from the solenoid with cleaning filter at container
pressure of the secondary diaphragm in the
pressure and reduces this pressure in two stages
vaporiser (6). This counterpressure closes the
to a pressure slightly below atmospheric pressure
control valve in the vaporiser (6) a little, reducing
(vacuum).
the flow of gas and preventing the mixture from
becoming too rich.
Function off position
• Ignition switch (7) opened. Shutdown
• Electromagnetic shut-off valve (4) closed. When disconnecting the ignition lock (7), the
• Throttle (10) in the mixer (9) closed. electromagnetic shut-off valve (4) is closed by
the ignition controller (20). At the same time, the
Function operating position LTC (15) activates the positioning magnet (11)
and the throttle (10) is aligned against the stop
• Ignition switch (7) closed. screw.
• Electromagnetic shut-off valve (4) closed.
A speed of 700 ± 100 rpm has to be set using the
stop screw to prevent the throttle from closing. All
Start travel and operating functions are shut down by
During the starting process, the ignition controller the LTC (15).
(20) receives a speed signal from the speed Furthermore, the ignition controller (20) allows
sensor (19) and opens the electromagnetic ignition sparks to reach the cylinder. Gas still
shut-off valve (4). At the same time, the LTC present in the LPG installation combusts with
control unit (15) opens the throttle (10) via the brief afterrunning of the engine occurring.
positioning magnets (11). Passing through the
open throttle, the engine vacuum reaches the If the afterrunning of the engine (12) lasts for
secondary diaphragm of the vaporiser/pressure more than 20 seconds, the ignition controller
regulator (6) via the piston of the mixer (9), (20) detects a leaky electromagnetic shut-off
opening the secondary valve. valve (4). The fault light (3) lights up. The ignition
controller (20) locks the release of ignition sparks
Depressurised gas now flows to the mixer via for 65 seconds after disconnection of the ignition
the secondary valve. The gas is mixed with air lock (7). The LPG cylinder must be closed at this
here and supplied as an ignitable mixture to the time.
cylinders.
The fault light (3) lights up again in the event of
fault at every start. It can be extinguished only by

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fixing the fault and when the fault display in the

E-control software diagnosis is deleted.

Vaporiser - functions

1 Primary valve 7 Bore

2 Secondary diaphragm 8 Primary diaphragm
3 Spring 9 Vaporising chamber
4 Lever 10 Heating passage
5 Vacuum hose port 11 Valve pin with spring
6 Secondary valve

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Vaporiser off position

When the vaporiser is in the off-position (engine
shut off), the primary valve (1) is open, the se-
condary valve (6) is closed by the spring (3). The
secondary valve (6) prevents the gas from flo-
wing out when the engine is shut off.
Vaporiser operating position
The primary valve (1) is controlled by the pres-
sure in the vaporising chamber (9), acting on the
primary diaphragm (8). This pressure passes
through the drilled passage (7) into the cham-
ber upstream from the diaphragm. The valve pin
(11) transfers the movement to the primary valve
(1) (area valve). The spring below the valve pin
(11) establishes the counterpressure. Behind the
primary diaphragm (8) there is atmospheric pres-
sure which is produced by the balancing hole.
With the engine running (throttle of mixer is open),
a vacuum is created in the fuel line to the mixer,
which opens the secondary valve (6) allowing the
LP gas to flow through the open primary valve (1)
into the vaporiser. The secondary diaphragm (2)
controls the secondary valve (6).
Due to the reduction of the LP gas pressure (ap-
prox. 10 bar in the LPG cylinder), the LP gas
expands to atmospheric pressure, causing it to
cool. To compensate for the cooling and to acce-
lerate the vaporisation, the vaporiser is heated.
The vaporiser is heated by cooling water passing
through the heating passage (10) in the vapo-
riser. Depending on the position of the throttle 1 Primary valve
(dependent on the position of the accelerator 2 Secondary diaphragm
pedal), the secondary diaphragm (2) is drawn in 3 Spring
more or less, which controls the opening of the 4 Lever
secondary valve (6). 5 Vacuum hose port
6 Secondary valve
Depending on engine speed and the load on 7 Bore
the engine, the vacuum behind the secondary 8 Primary diaphragm
diaphragm (2) in the secondary section of the 9 Vaporising chamber
vaporiser either increases or decreases. This 10 Heating passage
changes the gas flow on the secondary valve (6). 11 Valve pin with spring

If a restricted air filter increases the vacuum, this

vacuum counteracts the opening pressure of the
secondary diaphragm (2) through port (5). This
causes the secondary valve (6) to close a little,
reducing the gas flow and preventing the mixture
from becoming too rich.
When the engine is shut off, the vacuum at port
(5) increases. The secondary valve (6) closes
completely. No more gas can flow to the mixer.

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Mixer - functions

1 Gas inlet 7 Vacuum port for vacuum advance diaphragm

2 Full load mixture adjustment screw 8 Diaphragm
3 Vacuum port for shut-off valve 9 Flow control valve
4 Mixture outlet to intake pipe 10 Spring
5 Throttle plate 11 Suction air inlet
6 Idle mixture adjustment screw 12 Hose for vacuum control of diaphragm

The correct gas-air mixture ratio is important

for the proper operation of the engine. A mixing
valve (the mixer) is used for the correct metering
of the gas and air.

Method of operation
When the engine is started (throttle plate (5)
open), there is a vacuum in the space below the
piston (8), which is created during the intake
stroke of the engine piston. This vacuum is con-
ducted through a hose (12) to the underside of
the diaphragm (8) and moves it down against the

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LPG engine

pressure of the spring (10), and therefore the gas

metering valve (9). This movement can conti-
nue until the gas metering valve (9) is completely
open.
The vacuum fluctuates depending on the engine
speed and the position of the throttle plate (5). .
The gas metering valve (9) is connected to the
diaphragm (8) and formed so that for every po-
sition of the diaphragm (8) the correct amount
of gas is always metered and mixed with the air
flowing in. The mixer allows two limited mixture
adjustments.

Idle mixture adjustment

The air and gas passing the closed throttle plate
(5) when the engine is idling is constant.For the
idle adjustment a part of the inflowing air is guided
around the air intake valve. The idle is adjusted
with the idle mixture adjustment screw (6) with
which the gas-air mixture is made richer or leaner
during idle.

Full load mixture adjustment

This adjustment controls the mixing ratio when
the gas metering valve (9) is open. The adjust-
ment only takes effect when the engine reaches
the full load condition. The adjustment of the full
load mixture adjustment screw (2) can only be
carried out when the engine is under full load and
running at its speed limit (rated speed).
Between idle and full load conditions, the mixture
is formed by the form of the gas metering valve.
The gas metering valve (9) is formed so that the
mixture is lean when the load is low and enriched
progressively as the engine load and speed in-
crease.

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LPG shut-off valve

1 Shut-off valve
2 Solenoid valve connection
3 Vaporiser cover (no pushbutton)

The LPG shut-off valve consists of two compon-

ents:
• Shut-off valve The shut-off valve has a protec-
tive diode for the relay.
• Filter

CAUTION

Incorrect polarity when connecting the lines may

destroy the diode.
Positive and negative terminals must not be in-
terchanged.

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Gas failure cut-off

1 Warning light (0H1) 4 LPG shut-off valve (1Y6)

2 Ignition switch (S1) 5 Ignition coils (0T1) to (0T6)
3 Traction and lift control LTC (N1) 6 Electronic ignition control (0N1)

Method of operation The warning light (1) is then illuminated red. In

this case the shut-off valve on the LPG cylinder
When the LPG engine is shut off with the ignition must be closed immediately. Please also refer to
switch (4), all lift and driving function are cut out by the operating manual for series 394 T.
the LTC (5). The ignition control unit (2), however,
continues to apply power to the ignition coils (6). The diagnostic software displays the fault “Fuel
for a maximum of 65 seconds. The LPG shut-off run out longer than expected”.
valve (3) is closed immediately by the ignition ¾ Correct the problem.
control unit (2) when the ignition switch (4) is
turned off. ¾ Turn the ignition off and on.
Depending on the temperature of the LP gas, ¾ Delete the fault in the diagnostic software.
the engine can continue to run another 2 to 20 After an after-running of 65 seconds, the ignition
seconds maximum. control cuts off the current to the ignition coils. In
If the engine continues to run longer than 20 se- this case the engine is also shut off in the event of
conds, the gas failure cut-off is defective. Pos- a leak at the LPG shut-off valve.
sible cause is a leak at the LPG shut-off valve.

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LPG system leakage test

After the completion of the maintenance or re-
pairs, a leakage test must be carried out on the
LPG system.

Required test aids

• Leakage spray or soap solution
• Pressure gauge with ports, Part No. xxxxxx

Test procedure

NOTE

LPG trucks may only be repaired, serviced and

tested in well ventilated workplaces.
¾ Connect the pressure gauge to the hose Part
No. xxxx.
Do not forget to install a seal under the union nut.

¾ Connect the hose with pressure gauge to the

closed gas bottle.

WARNING

The test hose is too short and might suffer da-

mage if the gas bottle mount is pivoted out fully.
Do not carry out the inspection with the mounting
fully pivoted.

¾ Open the gas bottle with the engine stationary.

The gas pressure reading on the gauge should
range from about 5 to 10 bar. The pressure de-
pends on the temperature.
¾ Record the pressure reading.
¾ Check the entire high-pressure section with
leakage spray.

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¾ Check the gas bottle valve.

¾ Check the fittings.

¾ Check the gas outlet at the vaporiser.

There should be no bubbles forming.
Leave the LPG system unchanged for 10 minu-
tes. During this time there should be no great
change in temperature, otherwise the gas pres-
sure will change and the leakage test was use-
less.
¾ After 10 minutes read the gas pressure on the
pressure gauge again.
The gas pressure should be nearly identical to
the first reading.

NOTE
Gas diffuses through the hoses. This is the re-
ason for pressure drops after a longer standstill
of the fork truck, for example, overnight.

Catalytic converter without Lambda control

Mixer - basic setting
The engine must at operating temperature for the
test and adjustment.

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LPG engine

The firing point is set by the electronic ignition and

adjusted by the manufacturer. Desired 20 ±2°
BTDC in lower idle (1000 ±10 rpm).

Pretension of solenoid - adjustment

2 Adjusting rod 5 Solenoid

4 Lever 6 Solenoid shaft

¾ Remove the boot on the solenoid (5).

¾ Detach the adjusting rod (2).
¾ Determine dimension x at the solenoid shaft
(6). Example: 10 mm.
¾ Install the adjusting rod (2) on the lever (4).
¾ Adjust the adjusting rod (2) until the solenoid
shaft (6) has reached the dimension x +1 mm.
Example: 10 mm + 1 mm = 11 mm.
¾ Lock the adjusting rod (2) and install the boot.

Basic setting - throttle plate stop screw

¾ If the ignition is switched off, disconnect the
plug from the solenoid.
¾ Start the engine.

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LPG engine

¾ Check the speed with the stop screw.

Desired speed: 700 ±100 rpm
¾ If the ignition is switched off, install the plug on
the solenoid.

Basic setting gas installation

¾ Put the full load adjustment (tap) to (R).
¾ Fully close the idle screw.

CO content idle mixture

¾ Turn the idle mixture adjustment screw (1) in
against the stop.
¾ Connect the CO tester.
¾ Start the engine and test the CO content at
lower idle (1000 ±10 rpm) when the truck is at
operating temperature.
Desired value: If CO < 0.05 percent by volume,
lambda = 1.10 - 1.25.
If CO > 0.05 percent by volume, turn the idle mix-
ture adjustment screw(1) out one turn.

CO content - full load mixture

If CO < 0.05 percent by volume, a speed of n =
2800-100 rpm must be achieved.
If CO > 0.05 percent by volume,

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LPG engine

¾ turn the tap in the direction of (L) until CO < 0.05

percent by volume.
¾ Secure the adjustment screws and tap with
enamel.

Catalytic converter with Lambda control

Exhaust gases - composition

Exhaust gases - introduction Carbon monoxide (CO): Carbon monoxide

is a colourless and odourless gas. It has a
The fuel combustion in the cylinders of an engine considerably higher affinity to the hemoglobin
is more or less incomplete. The more incomplete (red blood dye) of the blood than does oxygen,
the burning, the greater the amount of pollutants and is thus toxic for the body.
in the exhaust gas. There is no such thing as a
complete combustion of fuel, even if there is ex- Nitrogen oxide (NO, NOX): Nitrogen oxide NO
cess oxygen in the air. To reduce the pollution of is a colourless gas oxidising to NO2 in the air. It
the environment, the exhaust gas characteristics is known as a severe hemotoxin, as it combines
of the spark ignition engine must be improved. with the hemoglobin in the blood to cause rapid
All measures for reducing pollutant emissions central paralysis. NO2 is a reddish-brown gas
limited by different laws and regulations have the with a sharp, pungent odour. It irritates the
aim of achieving a minimum of pollutant emissi- lungs and causes damage to the lung tissues.
ons with as much fuel economy as possible, with In combination with unsaturated hydrocarbons,
high performance and good driving characteris- nitrogen oxides cause smog formation under the
tics. influence of sunlight. NO and NO2 are designated
together as nitrogen oxides (NOx).
In addition to a high percentage of unharmful
matter, the exhaust gas of a spark ignition engine Hydrocarbons (HC): The exhaust gas contains
contains also contains components considered a variety of hydrocarbons:
to be harmful for the environment at least in higher Saturated hydrocarbons (paraffins) are almost
concentrations. The harmful part makes up about odourless, have a narcotic effect and cause a
one percent of the exhaust gases and it consists light irritation of mucous membranes.
of carbon monoxide (CO), nitrogen oxides (NOx)
and hydrocarbons (HC). The greatest problems Unsaturated hydrocarbons (olefins, acetylenes)
posed hereby are the opposite concentrations have a slightly sweetish smell and in some cases
of CO and HC on the one hand and NOx on the lead to an irritation of mucous membranes.
other, dependent on the air-to-fuel ratio. They play a considerable role in the formation
of smog, since in the presence of NO and under
Exhaust gases - properties the influence of sunlight they react further to form
oxidants and simultaneously also ozone.
The major components of the exhaust gases
Aromatic hydrocarbons have a characteristic
are nitrogen, carbon dioxide and water vapour.
odour. They are nerve toxins with a narcotic
These are non-poisonous.
effect, have a pungent smell and irritate eyes and
nose even at very low concentrations.

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Lambda control

1 Coolant temperature sending unit 10 Gas bottle/gas tank

2 Lambda sensor 11 Shut-off valve and filter
3 Three-way catalytic converter 12 Vaporiser
4 Speed sensor 13 Throttle plate actuator
5 Ignition coil 14 Control Valve
6 Control unit 15 Mixer
7 Diagnostic cable 300 365 2504 16 Pressure and temperature sending unit
8 Fault light 17 Air filter
9 Diagnostic software 18 Phase sensor

Lambda control - description

The lambda control in conjunction with the ca-
talytic converter represents the most efficient
exhaust gas cleaning process for spark ignition
engines available today.
The use of the three-way catalytic converter is es-
pecially effective. This catalyst is able to reduce
hydrocarbons, carbon monoxide and nitrogen
oxide by more than 90 % when the engine is ope-
rated in a very limited margin of error (±1 %) to
keep the stoichiometric air-fuel ratio to lambda =
1.
The stoichiometric air-fuel ratio is the theoretical
mass ratio of 14 kg of air to 1 kg of LP gas required

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for total combustion. The air ratio (lambda) indi-

cates how much the actual existing air-fuel mix-
ture deviates from the theoretical value.
Lambda = supplied mass air flow : theoretical
mass air flow
The lambda control controls the fuel quantity
so that the air-fuel mixture allows a nearly total
combustion.
Lambda sensor - structure and layout
The lambda sensor in the exhaust pipe uniformly
captures the exhaust flow from all cylinders. The
sensor ceramic is located in a housing, which
protects against mechanical influences and is
also used for mounting. The external part of the
ceramic monolith is located in the exhaust flow,
the internal part is in contact with the ambient air.

Lambda sensor - functional description 1 Contact

2 Protective ceramic tube
The ceramic material used becomes conductive
3 Sensor ceramic
for oxygen ions starting at about 300 °C. If the 4 Protective tube on exhaust gas end
amount of oxygen on both sides of the sensor is 5 Electric lead
different, an electric voltage is created between 6 Belleville spring
the two surfaces. This serves as a measure of the 7 Protective sleeve, on air end
difference in the oxygen concentration on the two 8 Housing (-)
sides of the sensor. The residual amount of oxy- 9 Electrode (+)
gen in the exhaust gas of an IC engine depends 10 Electrode (-)
to a large degree on the air-fuel ratio of the mix-
ture supplied to the engine. Even when operating
with excess fuel in the mixture, there is still some
oxygen in the exhaust gas. This relation makes
it is possible to use the oxygen concentration in
the exhaust gas as a measure of the air-fuel ratio.
The voltage supplied by the lambda sensor as
a result of the oxygen content in the exhaust is
800 - 1000 mV with a rich mixture (lambda < 1)
and only 100 mV with a lean mixture (lambda >
1). The transition from the rich to the lean range
is 450 - 500 mV.
In addition to oxygen concentration in the ex-
haust, the temperature of the ceramic body also
plays a crucial role as it influences the conducti-
vity of the oxygen ions. The characteristic curve
of the voltage supplied as a function of the excess
air factor is greatly influenced by the temperature.
The given values therefore apply for an operating
temperature of approx. 600 °C. The response
time for a change in voltage after a change in the
composition of the mixture also depends very
much on the temperature. If these response ti-
mes are in the range of seconds for a ceramic
temperature under 350 °C, the sensor already
responds in less than 1 ms at the optimum ope-
rating temperature of about 600 °C. That is why

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the Lambda control is shut off after the start of the

engine until the minimum operating temperature
of about 350 °C is achieved. During this time the
engine is operated under open-loop control. Ex-
cessive temperatures shorten the operating life.
The lambda sensor must therefore be installed
so that a temperature of 900 °C to 1000 °C is
not exceeded during a longer full load condition.
1200 °C are allowed for short periods.
Lambda sensor - heated
For this sensor type the temperature of the cera-
mic monolith at a low engine load (ie low exhaust
gas temperature) is determined by the electric
heater, at a high load by the exhaust gas tem-
perature. The heated lambda sensor allows
installation at a greater distance from the engine
so that even continuous full load work cycles are
unproblematic. The external heater allows ra-
pid heating so that the operating temperature is 1 Sensor housing
achieved within 15 - 60 s after the start of the en- 2 Ceramic support pipe
gine, thus enabling the lambda control. 3 Connecting cable
4 Protective pipe with slots
5 Active sensor ceramic
6 Contact
7 Protective sleeve
8 Heating element
9 Heating element terminals

Lambda control - functional description

The lambda sensor sends a voltage signal to
the electronic control (200 - 800 mV), which in
turn controls the control valve (1) with a PWM
(Pulse Width Modulation) signal. The control
valve is used to make the mixture either richer
or leaner. For this purpose a control threshold of
approx. 500 mV is programmed into the control.
If the voltage emitted by the lambda sensor is
below this value (mixture too lean), more LP gas
is added. If the limit is exceeded (mixture too
rich), the amount of LP gas is reduced again with
the control valve.
The modulation of the amount of LP gas is ef-
fected with the control valve, which actuates the
secondary diaphragm of the vaporiser according
to the PWM (Pulse Width Modulation) signal from
the control. If more LP gas (richer mixture) is re-
quired, the port (2) is closed. As a result, only
the slight vacuum of the intake air acts on the
secondary side of the vaporiser. The vaporiser
opens the secondary valve completely. 1 Control Valve
2 Port to vaporiser / pressure regulator (secondary
If more LP gas (richer mixture) is required, the diaphragm)
port (1) is opened. A large vacuum exists at the
secondary diaphragm, which further closes the
secondary valve, so that less LP gas flows to the
mixer and the mixture becomes leaner.

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The change in the air-fuel ratio, however, may

not be made abruptly, otherwise the truck would
tend to bucking. That is why is the electronic
control contains an integrator, which changes
the composition of the mixture slowly with a time
function. Some time elapses from the moment
the fresh mixture is formed in the LPG mixer un-
til the burned mixture is captured by the lambda
sensor (dead time). The dead time is caused by
the time the fresh mixture requires to reach the
engine, the time required for the work cycles of
the engine, the time required for the combusted
exhaust gas from the engine to reach the lambda
sensor and the response time of the lambda sen-
sor. This dead time makes a constantly exact
mixture impossible. The air-fuel ratio rather con-
stantly varies a few tenths of a percent around
lambda = 1. In case of a correct adjustment of
the integrator, however, the mean value of the
air-fuel ratio stays exactly within the converter
window, ie in a range in which the catalytic con-
verter achieves the maximum conversion.

Lambda control - functions of the control

The control
• controls the control valve
• assumes not only the lambda 1 control, but
also the ignition timing
• recognises the load condition of the engine via
a temperature and pressure sending unit. This
is important for determining the firing point and
for the formation of the mixture
• stores data and evaluates them. This allows
changes (wear or damages) to be detected
and measures to be taken
• reads the current lambda value and allows it to
be indicated on a display

NOTE

Except for the basic setting, the gas or ignition

system does not require any adjustments.

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Lambda sensor - control range

Three-way catalytic converter

The three-way catalytic converter has the cha-
racteristic of simultaneously removing all three
pollutants (CO, HC, NO) to a high degree. The
three-way catalytic converter combined with the
lambda control is the most effective pollutant re-
duction system currently available.

1 Lambda control range

2 Voltage characteristic of the lambda sensor
3 Air ratio lambda
4 Exhaust emission and sensor voltage

Three-way catalytic converter - construction

1 Steel housing 5 Lambda sensor

2 Support 6 Electronic control (computer)
3 Active catalytic layer 7 Control valve at vaporiser / pressure regulator
4 Three-way catalytic converter (NOx, HC, CO)

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Metal monolithsrequire a substrate coating of

aluminium oxide (“wash coat”), which enlarges
the effective surface area of the catalytic conver-
ter by about the factor 7000.
The effective catalytic layer on it is made of pla-
tinum and rhodium in three-way catalytic con-
verters. Platinum speeds up the oxydation of
hydrocarbons (HC) and carbon monoxide (CO),
rhodium reduces the nitrogen oxides (NOx).
The rare metal content in a catalytic converter is
approx. 2 to 3 grams.

Three-way catalytic converter - operating

1 Platinum and rhodium coating
conditions 2 Ceramic or metal monoliths (honeycomb)
A notable conversion of the pollutants only begins
at an operating temperature of over 250 °C. Ideal
operating conditions prevail at temperatures ran-
ging from approx. 400 °C to 800 °C. In the range
of 800 °C to 1000 °C, thermal aging is aggravated
significantly by the sintering of the noble metals
and substrate coating, which leads to a reduction
in the active surface area.
The period of operation in this temperature
range, therefore, exerts a great influence. Above
1000 °C thermal aging is severely aggravated
up to almost total ineffectiveness of the catalytic
converter.
Engine malfunctions, for example misfires, can
cause the temperature of the catalytic converter
to rise over 1400 °C. Such temperatures lead to
the complete destruction of the catalytic conver-
ter through melting of the substrate material. Re-
sidues from the engine oil (due to a high engine
oil consumption) can also lead to a destruction
(poisoning) of the catalytic converter.

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Diesel engine

Description of transmission
Technical data for BJC
Manufacturer VW
Type of engine BJC (TDI industrial engine with charge air cooler)
Number of cylinders 4
Cubic capacity 1896 cm3
Power 36 kW at 2600 rpm
Max. torque 215 Nm at 1800 rpm
Injection nozzle pressure 220 bar, wear limit 200 bar
Compression ratio 19,5 : 1
Compression 25 - 31 bar, wear limit 19 bar
Maximum admissible pressure difference 5 bar
Lower idle speed 1000 rpm
2700 rpm when driving
Upper idle speed
2800 rpm with working hydraulic system
Valve clearance Self-adjusting
Firing order 1-3-4-2
Position of cylinder 1 Opposite power takeoff side
Thermostat start of opening: 87 °C, fully open at
Thermostat
102 °C
Diesel fuel acc. to DIN EN 590, RME-based
Fuel
biodiesel possible
Number of teeth on flywheel 135
Oil pressure at 2000 rpm and an oil temperature of
At least 2 bar
80 °C

Explanation of engine identification: The Structure of engine number:Example: BJC /

engine identification letter and the engine number 002141 (type of engine / consecutive number)
are stamped on the left side of the cylinder block
above the fuel pump. There is also a plate on the
toothed belt cover.

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Special features of the 1.9-litre BJC

engine
• Distributor fuel injection pump with a pump
pressure of 800 bar. The distributor fuel injec-
tion pump is preset.

NOTE

The flange is pressed on to the driveshaft and

may not be removed.

• The intake passage is formed as a swirl pas-

sage. It imparts the intake air as a swirling
motion, thus providing for an intensive air swirl
in the combustion chamber.
• Specially shaped piston cavity (main combus-
tion chamber).
• Water pump installed in the cylinder block.
• Coolant thermostat installed in cylinder block.
• Plastic-coated injection lines as a protection
against corrosion.
• Vulcanised cylinder head cover gasket.
• Oil sump with silicone sealant.
• Change oil filter as paper cartridge.
• Vacuum pump drive driven by the camshaft.
Control unit for direct injection system
0N1
Due to the high requirements placed on fuel
economy and emissions, the injection rate and
injection timing are controlled electronically. This
job is assumed by the Electronic Diesel Control
(EDC). It determines the fuel rate and start of in-
jection of the distributor fuel injection pump and
controls the preheating time.

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Diesel engine

The electronic engine control unit

Sensor 10 Glow plugs (engine) 0R1

1 Needle stroke sensor 0B5 12 Solenoid valve for charge pressure limitation 0Y4
2 Engine speed sensor 0B2 13 Indicator light for preheating time H8
3 Mass air flow sensor 0B6 14 Fuel quantity positioner
4 Coolant temperature sending unit 0B1 15 Fuel shut-off valve 0Y1
5 Temperature and pressure sending unit 0B4 16 Start of injection valve 0Y2
6 Control sleeve position sensor 0B3 17 Additional signals for engine speed, fuel con-
7 Fuel temperature sending unit 0B3 sumption, air conditioning
8 Additional signals; air conditioning, terminal DFM
Plugs
Actuators 18 Diagnostic plug 6X2
9 Glow plug relay 0K1

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Sensor
Coolant temperature sending unit 0B1
The coolant temperature sending unit is located
in the coolant neck on the cylinder head. The
sensor is designed as a resistor with a negative
temperature coefficient (NTC). The momentary
value of the coolant temperature is transmitted to
the electronic control unit by a drop in voltage.

Coolant temperature sending unit - signal

evaluation
The signal for the coolant temperature is taken
into account for the calculation of the fuel quantity
to be injected, the start of injection and the prehe-
ating time.

Coolant temperature sending unit - sub-

stitute function
In case of a problem with this signal, the fuel
temperature is used as a substitute signal. The
maximum possible time is used for the prehea-
ting time.

Coolant temperature sending unit - self-

test
The following faults are stored as possible cause:
• short circuit to earth
• interruption/ short circuit

Coolant temperature sending unit - check

Required special tools

• Laptop with software
• Test adapter 7 917 299 010
• Multimeter
• Wiring diagram

Test procedure
¾ Connect the laptop and start the software.
¾ “Select Inputs and outputs - Group 07”. The
engine must be idling.
¾ Check the coolant temperature in Display
field 4. The temperature value should rise uni-
formly without interruptions.
In the event of a fault, the fuel temperature or the
value -4.5 °C is indicated instead.

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If Display field 4 does not show a realistic read-out

or shows the fuel temperature or the value -4.5 °C
instead, check the coolant temperature sending
unit and the line connections to the sensor as
follows:
¾ Terminate the communication between truck
and laptop.
¾ Turn off the ignition.
¾ Pull the plug from the sensor.
¾ Measure the resistance between contacts (1)
and (2) on the sensor.

¾ Read the desired resistance on the diagram

Diagram A shows the resistance values for the
temperature range 0 - 50 °C, diagram B the va-
lues for the temperature range 50 - 100°C.
Examples of readings
30 °C corresponds to a resistance of 1500 -
2000
80 °C corresponds to a resistance of 275 - 375
If the desired resistance is not obtained:
¾ Replace coolant temperature sending unit
0B1.
If the desired resistance is obtained:
¾ Connect the test adapter to the cable loom of
the engine control unit.
¾ Using the wiring diagram, check the lines bet-
ween the test adapter and the 4-pin connector
for interruptions.
Max cable resistance 1.5
¾ Also check the lines for line-to-line shorts,
short circuit to truck earth and to battery posi-
tive.
Desired resistance: 8
If no fault in the lines is detected:

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¾ Replace the control unit of injection system

0N1.

Engine speed sensor 0B2

The engine speed is one of the most important
parameters for calculation of the injection quan-
tity and the start of the injection process. The
inductive sensor 0B2 for the engine speed moni-
tors the angular position of the crankshaft. The
sensor wheel (a disc with four slots) is moun-
ted on the crankshaft. The correct position is
fixed with a dowel pin. The electronic control unit
measures the gap between two successive pul-
ses. The momentary value of the position of the
crankshaft is calculated by evaluating the four
impulses.

Engine speed sensor - signal evaluation

The speed signal is used for the calculation of fuel
quantity to be injected and the start of injection.
The signal of the engine speed sensor is used for
carrying out the functions exhaust gas recircula-
tion, preheating and signal to the preheating time
indicator light.

Engine speed sensor - self-test

Two possible fault causes are stored in the elec-
tronic control unit:
• Signal not plausible
• No signal

Engine speed sensor check

The engine speed sensor provides the en-
gine rpm and reference marks. When it fails, the
engine stops.

Required special tools

• Test adapter 7 917 299 010
• Multimeter
• Wiring diagram

Test procedure
¾ Turn off the ignition.

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¾ Disconnect the connector at the engine speed

sensor.

¾ Measure the resistance between contacts (1)

and (2) of the male connector.
Desired value 1.1 k to 1.6 k
If the specified value is not obtained:
¾ Replace engine speed sensor 0B2
If the desired value is obtained:
¾ Connect the test adapter to the cable loom of
the engine control unit
Max cable resistance 1.5
¾ Using the wiring diagram, check the lines bet-
ween the test adapter and 3-pin plug for shorts.
Desired value: 8
¾ Measure contacts 1, 2 and 3 for interruptions
• Contact 1 and socket 102
• Contact 2 and socket 110
• Contact 3 and socket 86
Max cable resistance 1.5
If no fault is detected in the lines:
¾ Replace control unit of fuel injection system

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Fuel temperature sending unit 0B3

The fuel temperature sending unit 0B3 (1)

measures the temperature of the fuel in the injec-
tion pump. The measuring result is transmitted to
the electronic control unit as a change in voltage.
The temperature of the fuel is very important,
because the density of the fuel depends directly
on its temperature. The fuel is pressed under
high pressure through the injection nozzles by
a small piston in the injection pump. The tem-
perature of the fuel must be known for the exact
determination of the injection rate and the start of
injection. The correct values can be calculated
with the known connection between temperature
and density.

Fuel temperature sending unit - signal

evaluation
The fuel quantity to be injected and the start of
injection are calculated on the basis of the signal
of the fuel temperature sending unit.

Fuel temperature sending unit - substi-

tute function
In case of a sensor failure, the electronic control
unit presets a constant value as a basis for calcu-
lation.

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Fuel temperature sending unit - self-test

The electronic control stores the following fault
causes:
• short circuit to earth
• Interruption/ short circuit

Fuel temperature sending unit - check

Required special tools

• Laptop with software
• Test adapter 7 917 299 010
• Multimeter
• Wiring diagram

Test procedure
¾ Connect the laptop and start the software
¾ Select menu item “Inputs and outputs -
Group 07”.
The engine must be running at idle speed.
If no realistic reading is shown in the Display field
or an operating temperature of -5.4 °C is indica-
ted, check the fuel temperature sending unit and
the cable connections to the sensor.
¾ Turn off the ignition.
¾ Disconnect the 10-pin connector of the fuel
temperature sending unit (connector to quan-
tity regulating unit of the injection pump).

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¾ Measure the resistance of the sensor at con-

tacts (4) and (7) of plug.
Diagram A shows the resistance values for the
temperature range 0 - 50°C, diagram B , the va-
lues for the temperature range 50 - 100°C.

¾ Read in the diagram

30 °C is in diagram A and corresponds to a resis-
tance of 1.5 - 2.0 k
80 °C is in diagram B and corresponds to a resis-
tance of 275 - 375
If the specified value is not obtained:
¾ Replace the injection pump
¾ Read out the fault history of the engine control
unit.
¾ If necessary, clear the fault history
If the desired value is obtained:
¾ Connect the test adapter 7 917 299 010 to
the cable loom of the engine control unit. This
does not connect the control unit.
¾ Using the circuit diagram, check the lines bet-
ween test adapter and the connector for inter-
ruptions
• Contact 7 and socket 111
• Contact 4 and socket 103
Line resistance: max 1.5
¾ Also check the lines for line-to-line shorts,
short to battery earth/engine earth and to bat-
tery positive
Desired value: 8
If no fault is detected in the lines:
¾ Replace the control unit for direct injection
system 0N1.

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Intake pipe temperature and intake

pipe pressure sensor 0B4
The sensor is located in the intake pipe. Its signal
provides information on the air temperature in the
intake manifold.
The signal of sensor 0B4 is used for control pur-
poses.

Intake pipe temperature and intake pipe

pressure sensor - Substitute function
In case of a failure of sensor 0B4, the electronic
control unit specifies a fixed value. In this case
the electronic control unit takes a value of approx.
20 °C as a basis for calculation.

Intake pipe temperature and intake pipe

pressure sensor - Self-test
The control unit stores two possible malfunctions:
• Short circuit to earth
• Interruption/ short circuit

Required special tools for the test

• Laptop with software
• Test adapter 7 917 299 010
• Multimeter
• Circuit diagram

Prerequisites for the test

The engine must run at idle speed.
¾ Connect the Laptop
¾ Start the software
¾ Select menu item “Inputs and outputs -
Group 7”.
If no realistic reading is shown in the display field
• or
• an operating temperature of 136.8 °C
is indicated, check the intake pipe temperature
sensor and the cable connections to the sensor
¾ Turn off the ignition

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¾ Disconnect the 2-pin plug from the intake pipe

temperature sensor 0B4

¾ Check the resistance between the contacts of

the intake pipe temperature sensor.
Area A shows the resistance values for the tem-
perature range 0 - 50 °C, area B, the values for
the temperature range 50 - 100 °C.
Examples of readings:
30 °C is in range A and corresponds to a resis-
tance of 1.5 - 2 k
80 °C is in range B and corresponds to a resis-
tance of 275 k to 375 k
If the specified value is not obtained:
¾ Replace intake pipe temperature sensor 0B4
¾ Read out the fault history of the engine control
unit
¾ If necessary, clear the fault history
If the desired value is obtained:
¾ Connect test adapter 7 917 299 010 to the
cable loom of the engine control unit. (The
engine control unit is not connected in this
case).
¾ Check lines between the test adapter and plug
for interruptions according to the circuit dia-
gram
• Contact 1 and socket 73
• Contact 2 and socket 54
Cable resistance: maximum 1.5
¾ Also check the lines for line-to-line shorts, for
shorts to battery negative and to battery posi-
tive
Desired value: ’
If no fault is detected:
¾ Replace the control unit for direct injection
system 0N1

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Needle stroke sensor 0B5

For the purpose of recording the start of the in-
jection, the injection nozzle of the 3rd cylinder
is equipped with needle stroke sensor 0B5.The
sensor monitors the actual time when the injec-
tion nozzle opens, and this signal is transmitted
to the control unit.The electronic control unit com-
pares the received signal with the characteristic
map for the start of injection and evaluates the
difference.
Needle stroke sensor - feature
The needle stroke sensor 0B5 consists of a sole-
noid (2), which is supplied with a constant current
by the control unit. As a result, a magnetic field
is created.Inside the solenoid there is a pressure
spindle (1) formed as an extension of the nozzle
needle. The movement of the pressure spindle
leads to a change in the voltage induced in the
solenoid.The time of induction of the voltage in
the coil is compared with the top dead centre
(TDC) signal by the control unit. The actual start
of injection is calculated from this difference.
Subsequently, the actual value for the start of in-
jection is compared with the desired value, and in
case of a deviation, the start of injection is correc-
ted accordingly.

Needle stroke sensor - substitute func-

tion
In case of a failure of the needle stroke sensor,
an emergency running program is started. With
this program, the start of injection is controlled
according to a specific characteristic map. The
injection quantity is also reduced.

Needle stroke sensor - check

The needle stroke sensor signal is required for
determining the start of injection. In case of a fai-
lure, the start of injection is controlled according
to speed and load; during regular operation, the
start of injection is controlled according to speed,
load and temperature.

Required special tools

• Test adapter 7 917 299 010
• Multimeter
• Wiring diagram

Test procedure
¾ Turn off the ignition.

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¾ Disconnect the needle stroke sensor connec-

tor.
¾ Measure the resistance between the contacts
of the male connector.
Desired resistance: 80 - 120
If the desired resistance is not obtained:
¾ Replace the injection nozzle of cylinder 3 with
needle stroke sensor 0B5.
If the desired resistance is obtained:
¾ Connect the test adapter to the cable loom of
the engine control unit. This does not connect
the control unit.
¾ Using the wiring diagram, check the lines bet-
ween test box and the 10-pin connector for
interruptions.
• Contact 1 and socket 109
• Contact 2 and socket 101
Line resistance: max 1.5
¾ Also check the lines for line-to-line shorts,
short circuit to truck earth and to battery posi-
tive.
Desired resistance: 8
If no fault in the lines is detected:
¾ Replace the control unit for direct injection
system 0N1.

Height sensor
The height sensor (1) is integrated in the control
unit for direct diesel injection 0N1. The measu-
rement is carried out directly in the control unit.
The height sensor contains a piezo-ceramic ele-
ment. If a force is applied to the piezocrystal, it
supplies a voltage. This voltage is a measure of
the air pressure. The air pressure depends on the
geographic height, ie the air pressure sinks with
increasing height. The charge pressure and the
exhaust gas recirculation are reduced in order
to prevent “black smoke”when the air pressure
drops.

Height sensor - signal evaluation

The electronic control unit calculates the charge
pressure limit value on the basis of the height
sensor signal.

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Height sensor - substitute function

In case of a failure of the height sensor, the
charge pressure is limited by a preset constant
value.

Height sensor - self-test

The electronic control unit stores any possible
faults.

NOTE

The height sensor cannot be repaired in case of a

malfunction. The electronic control unit must be
replaced.

Control sleeve position sensor 0B3

1 Coil with alternating voltage 4 Eccentric shaft

2 Iron core 5 Distributor fuel injection pump
3 Moveable iron ring 6 Fixed iron ring

Control sleeve position sensor - descrip-

tion
The sensor for the control sleeve position 0B3
monitors the angle of rotation of the eccentric
shaft of the fuel quantity positioner in the injection
pump. This sensor is a non-contact type sensor.

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Its signals are directly transmitted to the electro-

nic control unit. The sensor consists of two in-
ductive pick-ups, which work in accordance with
the differential transformer principle. The use of
non-contact pick-ups guarantees its correct ope-
ration independent of the surrounding medium
so that any water which might be in the fuel does
not lead to a falsification of the measuring result.
An alternating magnetic field is created by the al-
ternating voltage along an especially shaped iron
core. A moveable iron ring which can be moved
along the iron core is fixed on the eccentric shaft.
The alternating magnetic field changes in accor-
dance with the position of the moveable iron ring.
As a result, an alternating voltage is induced in
the coil. The phase shift of the induced voltage
in relation to the desired voltage is recorded as a
measure of the position of the fuel quantity positi-
oner. Temperature influences can be neglected,
since both voltages come from the same sensor
and are transmitted via the same line system.

Control sleeve position sensor - signal

evaluation
The sensor signal corresponds to the momentary
position of the fuel quantity positioner. It is used
for the comparison of the “actual position” of the
fuel quantity positioner with the position calcu-
lated by the electronic control unit. In case of a
difference between the desired and actual posi-
tion, the quantity regulating mechanism corrects
the position of the fuel quantity positioner.

Control sleeve position sensor - substi-

tute function
If the control unit does not receive a signal from
the sensor for control sleeve position 0B3, the
engine is stopped for safety reasons.

Control sleeve position sensor - test

The fuel quantity positioner is an electromagnetic
rotating actuator which is activated by the control
unit via a specific on/off ratio. The eccentric shaft
of the fuel quantity positioner moves the control
sleeve at the high-pressure piston, thereby deter-
mining the injection quantity.
The sensor for control sleeve position delivers
the control unit the position of the fuel quantity
positioner and so determines the volume of the
injection quantity.

Required special tools and aids

• Laptop with software

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• Test adapter 7 917 299 010

• Multimeter
• Wiring diagram

Prerequisites for the test

¾ Connect the laptop, start the software.
¾ Select menu item “Group 01 Inputs and out-
puts ”.
The engine must be running at idle speed.
¾ Check coolant temperature in Display field.
¾ Desired value: at least 80 °C
¾ Proceed with test only after coolant tempera-
ture is reached.
¾ Check the reading in the Display field (pump
voltage).
Engine identification letter BJC: Desired voltage:
1.86 V - 2.12 V
If the desired value is not reached, check the
sensor for control sleeve position and the fuel
quantity positioner.
Test
¾ Disconnect the 10-pin connector of the sensor
for the control sleeve position (connector to the
quantity regulating unit of the injection pump).

¾ Measure the resistance between contacts 1

and 2 and 2 and 3.
Desired value: 4.9 to 7.5 .
If the desired value is not obtained:
¾ Replace the injection pump
¾ Read out the fault history of the engine control
unit.
¾ If necessary, clear the fault history
If the desired value is obtained:
¾ Connect the test adapter to the cable loom of
the engine control unit. (The engine control
unit is not connected in this case).

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¾ Using the wiring diagram, check the lines bet-

ween the test adapter and plug for interrupti-
ons.
• Contact 1 and socket 108
• Contact 2 and socket 106
• Contact 3 and socket 99
Max cable resistance thereby 1.5
¾ Also check the lines for line-to-line shorts. Also
check the lines for short to battery earth, en-
gine earth and to battery positive
The desired resistance is 8
If no fault is detected:
¾ Replace control unit of fuel injection system

Actual speed sensor 1B1

Setting instruction
¾ Remove actual speed sensor.
¾ Turn flywheel until one of the teeth lies beneath
the borehole.
¾ Install actual speed sensor. Turn nut (1) down-
wards until the actual speed sensor rests on
the tooth of the flywheel.
¾ Set the clearance between actual speed sen-
sor and flywheel to s = 0.5+0.3 mm. Turn the
nut (1) by 0.75 to 1 rotation to the left.
¾ Bring nut (2) back to the installation and tighten
with 10 Nm
The functioning of the actual speed sensor can
be examined in the “Motor Data” window of the
diagnostic programme.

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Preheating system
Pre-heater system

1 Engine speed sensor 4 Glow plug relay

2 Sensor for coolant temperature 5 Glow plug
3 Control unit for direct diesel injection

High pressure and high temperature are ge- Pre-heater system - test
nerated in the combustion chamber during the
compression phase. This affects the combustion Required special tools
process substantially. Due to the small surface of
the combustion chamber, the heat dissipation is • Laptop with software
low. Pre-heating is only necessary at low tempe- • Multimeter
ratures. • Circuit diagram
Basically, there are three glow phases:
Prerequisites for testing
• Pre-heating time
• Glow time • The fuses must be okay.
• Post-heating time • The battery voltage must be at least 11.5 V.
• Earth connections okay.
Pre-heater system - control • All electric loads must be switched off.
The electronic control unit controls the pre-he- • No fault may be stored in the fault memory.
ater system. Pre-heating is only activated if the
coolant temperature is below +10°C. The colder Test Procedure
the coolant, the longer the pre-heating time. After
¾ Pull the connectors from the glow plugs.
pre-heating, the five-second waiting time is acti-
vated, during which glowing is active. Post-hea- ¾ Connect the multimeter for voltage measure-
ting is activated for about 30 s during the starting ments between a glow plug connector and the
procedure in case of coolant temperatures below battery earth/engine earth.
+20 °C. In total, a post-heating time of 90 seconds
¾ Carry out actuator diagnosis and energise the
is possible, depending on the coolant tempera-
glow plug relay
ture. In case of speeds exceeding 2500 rpm,
post-heating is switched off. The voltage value should vary between 0 V and
around the battery voltage.
Continue and finish the actuator test.
¾ Switch the ignition off.
If the voltage value does not vary as described:

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¾ Eliminate the fault in the lines to the glow plug ¾ Clear the fault memory if necessary.
relay (0K1) according to circuit diagram.
¾ Then poll the fault memory of the engine
control unit.

Engine glow plugs 0R1

The glow plugs (1)are arranged in such a way
that only their tips project into the combustion
chamber. A quick-connect coupling enables ra-
pid testing and replacement of the glow plugs.

Glow plugs - control

The relay for the glow plugs is switched via the
electronic control unit. It determines the prehe-
ating time, the glow-time and the post-heating
time.

Glow plugs - self-test

Faults in the preheating system are not stored.
The glow plugs and the preheating system are
tested with the function is used.“Actuator test”

Glow plugs - checking

Required special tools

• Diode test lamp
• Flexible head spanner VW 3229

Prerequisites for testing

• Battery voltage at least 11.5 V
• Ignition switched off

Test procedure
¾ Pull the connector from the glow plugs.
¾ Connect the line of the diode test light to bat-
tery positive (+) by using the auxiliary terminals
of the test aids set.

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¾ Place the probe of the diode test light succes-

sively on each glow plug.
• Diode lights up: glow plug ok.
• Diode does not light up: replace glow plug.
¾ Remove and install the glow plugs with the
flexible head spanner VW 3229.
Tightening torque: 15 Nm.

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Fuel supply
Fuel metering

1 Control unit for direct diesel fuel injection 5 Fuel temperature sending unit
2 Fuel quantity positioner 6 Coolant temperature sending unit
3 Additional signal 7 Speed sensor
4 Sensor for control sleeve position 8 Diagnostic plug 6X2

The electronic control unit controls the fuel quan-

tity positioner dependent on the parameters in-
jection rate, speed, torque, driving comfort and
starting. Depending on a stored characteris-
tic map value, the fuel quantity to be injected is
specified by various parameters transmitted by
sensors. Included in the control signal for the fuel
quantity positioner are also the following sensor
signals:
• LTC interrogation (CAN signal)
• Coolant temperature
• Fuel temperature
• Engine speed
• Control sleeve position

Executed functions
• Characteristic map value for injection quantity
• Control of idle and full load speed
• Overrun fuel cut-off
• Starting quantity control
• Smoke limitation

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Injection quantity characteristic map

The basis for the signal transmitted to the fuel
quantity positioner is a value taken from a cha-
racteristic map. This characteristic map signal
is modified by specific corrective factors in or-
der to modify the amount of fuel to be injected
as exactly as possible. The signal for the control
sleeve position is used as acknowledgement and
corrective value for the execution.

Governing idle and full load speed

Values for the idle- and full-load speed are spe- 1 Engine speed
cified in the controller unit. The full load speed 2 Fuel mass
is changed by the engine temperature, the con- 3 Start of injection
nection of electric loads and the air conditioning
compressor. The governing of the idle speed
starts when the engine speed data is taken from
its characteristic map, taking the coolant tem-
perature into account. This characteristic map
value is compared with actual engine speed. The
required injection quantity is calculated from the
difference. The maximum speed is always con-
stant. When this speed is reached, the injection
quantity is reduced progressively. If the speed
drops again, the injection quantity is increased.

Overrun fuel cut-off

The function overrun fuel cut-off cuts off the fuel
supply to the injection valves completely. This
function is always carried out when the idle speed
rises to over 1300 rpm without an increase in
speed being demanded.

Starting quantity control

The electronic control unit raises the injection
quantity when starting. The characteristic map
data for the injection quantity are raised in depen-
dence on the coolant temperature.

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Characteristic map for smoke

The quantity to be injected at any given time is
determined in accordance with the stored cha-
racteristic map for smoke.When the mass air flow
is too small, the injection quantity is reduced to
such a degree that no black smoke arises.

1 Engine speed
2 Mass air flow
3 Fuel mass

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Fuel quantity positioner 0B3

The fuel quantity positioner is located in the top
section of the injection pump. It translates the sig-
nals received from the electronic control unit into
a position change of the control sleeve. For this
purpose the received electric signals are transla-
ted into defined movements of the driveshaft with
eccentric ball-and-socket joint (1) by means of
the electromotive principle.
The driveshaft may carry out movements up to
a rotation angle of 60°. A spring provides for a
permanent righting moment of the driveshaft in
the direction of its initial position. The eccentric
ball-and-socket joint pushes the axially moveable
control sleeve on the distributor plunger back and
forth. During this process the control edge can be
fully opened (cut-off) and fully closed (full load).

Fuel quantity positioner - control

In the electronic control unit, the CAN signal of
the LTC controller and the signal for the engine
speed are used as parameters for controlling the
injection quantity.
In addition, the following corrective values are
taken into account:
• Coolant temperature
• Fuel temperature
On the basis of these parameters, the electronic
control unit calculates a manipulated variable,
1 Eccentric ball-and-socket joint
which is transmitted as a voltage to the fuel quan-
2 Control sleeve
tity positioner. 3 Distributor plunger
4 Leakage quantity
Fuel quantity positioner - substitute func-
tion
In case of a failure of the fuel quantity positioner,
the engine is stopped. In case of a failure of the
power supply the return moment of the spring
returns the driveshaft to its initial position. This
leads to the complete release of the control edge
of the distributor plunger and the engine stops.

Fuel quantity positioner - self-test

Any problems are detected in the electronic con-
trol unit.

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Fuel quantity positioner - check

¾ Disconnect the 10-pin connector to the quan-
tity regulating mechanism of the injection
pump.

¾ Measure the resistance between contacts 5

and 6 of the fuel quantity positioner.
Desired resistance: 0.5 - 2.5
If the desired resistance is not obtained:
¾ Replace injection pump
¾ Subsequently read out the fault history of the
engine control unit.
¾ If necessary, clear the fault history
If the desired resistance is obtained:
¾ Connect the test adapter to the cable loom of
the engine control unit. This does not connect
the control unit.
¾ Check the lines between the test adapter and
the 10-pin connector for interruptions accor-
ding to wiring diagram.
• Contact 5 and socket 1
• Contact 5 and socket 2
• Contact 6 and socket 116
• Contact 6 and socket 121
¾ Also check the lines for line-to-line shorts,
short to battery earth/engine earth and to bat-
tery positive.
If no fault in the lines is detected:
¾ Replace the control unit for injection system
0N1

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Fuel shut-off valve 0Y1

An auto-ignition engine can only be switched off
by cutting off the fuel supply. This is achieved
with the fuel shut-off valve 0Y1. The valve is loca-
ted in the top section of the injection pump. When
the power is cut off, it cuts off the fuel supply to the
distributor injection pump. The fuel shut-off valve
is a solenoid valve. The armature (3) also serves
as check valve. When the spool (1) is excited,
the armature is drawn in, the force of the spring
overcome and the flow of fuel released.

Fuel shut-off valve - control

The fuel shut-off valve is operated via a contact
of the electronic control unit. When the contact
opens, the power supply is interrupted and the
engine stops immediately.

Fuel shut-off valve - substitute function

In case of a failure, the vehicle is shut down im-
mediately as the fuel supply is cut off at once.

Fuel shut-off valve - self-test

A fault is registered by the electronic control unit.
When using the diagnostic software, the correct
state of the fuel shut-off valve is checked with the
help of the function “Actuator test”.

Injection timing device- replacement

of O-ring on cover
¾ Place a clean cloth underneath the injection
pump.
¾ Remove the cover screws (1) with a commer-
cial offset screwdriver for Torx head screws,
for example, Hazet 2115-T30.
¾ Remove and clean the cover (2).
¾ Replace the O-ring (3) and install the cover
with the existing shims (4).

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Start of injectionvalve 0Y2

1 Controller for direct fuel injection 0N1 8 Pin

2 Solenoid 9 Timing device plunger
3 Spring 10 Spring
4 Start of injection valve 0Y2 11 To suction side of vane-cell pump
5 Piston 12 Pressure roller
6 Fuel under pressure in pump interior 13 Injection pump
7 Cam plate

Valve 0Y2 for the start of the injection process is

mounted in the lower part of the injection pump. It
translates the on/off ratio into a change in the con-
trol pressure. This change acts on the part of the
timing device plunger which is not preloaded. The
valve is a solenoid valve. It consists of a piston, a
spring and a coil. In its neutral position, the piston
shuts off the fuel return flow through the force of
the spring. The return flow opening is opened by
the activation of the solenoid of the valve via the
electronic control unit. Due to the pressure of the
fuel acting on the piston and counteracting the
spring power, an equilibrium of forces is created
for each fuel pressure. This equilibrium provides
a defined position of the timing device plunger
and causes a shift in the start of injection. As a
result of the position change of the timing device
plunger, the pin is displaced.This displacement is
transmitted to the radially mounted cam in the in-
jection pump. Due to the connection between pin
and cam, the displacement of the pin is translated
into a specific angle. Consequently, the cam is

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turned into the direction “early” or “late” and the

start of injection is shifted accordingly.

Valve 0Y2 - control

For the calculation of the value for the signal to
the solenoid valve, the signal of the needle stroke
sensor is used as actual value parameter. The
electronic control unit transmits a pulse sequence
of constant frequency and a different phase angle
to the solenoid valve.

Valve 0Y2 - self-test

Malfunctions of the start of injection control are
stored in the fault history (interruption and short
circuit).

Valve 0Y2 - check

Required special tools

• Laptop with software
• Test adapter 7 917 299 010
• Multimeter
• Wiring diagram

Test procedure
¾ Connect the Laptop, start the software
¾ Select the menu item “Guided diagnosis - ac-
tuator test”. The engine must be running at idle
speed.
Activating the valve results in a clearly audible
change in the combustion noise (knocking).
Check the valve. If no change in the combustion
noise can be heard:
¾ Disconnect the 10-pin connector for the start of
injection valve (connector to the fuel quantity
positioner of the injection pump).

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¾ Measure the resistance between contacts 9

and 10 of the start of injection valve.
Desired resistance: 12 - 20
If the desired resistance is not obtained:
¾ Replace the start of injection valve 0Y1.
¾ Subsequently read out the fault history of the
engine control unit.
¾ If necessary, the clear the fault history
If the desired resistance is obtained:
¾ Connect the test adapter to the cable loom of
the engine control unit. This does not connect
the control unit.
¾ Using the wiring diagram, check the lines bet-
ween test box and the 10-pin connector for
interruptions.
• Contact 9 and socket 114
• Contact 10 and socket 1
• Contact 10 and socket 2
Max cable resistance 1.5
¾ Also check the lines for line-to-line shorts,
short to battery earth/engine earth and to bat-
tery positive.
Desired resistance: 8
If no fault in the lines is detected:
¾ Replace the control unit for the direct diesel
injection system 0N1

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Start of injection - governing

1 Controller for direct fuel injection 4 Engine speed sensor

2 Valve for start of injection 5 Needle lift sensor
3 Coolant temperature sending unit 6 Diagnostic plug 6X2

The start of the injection has an influence on

various engine characteristics such as starting
behaviour, fuel consumption and exhaust gas
emission. These correlations are taken into ac-
count in programmed characteristic maps for the
start of injection.
The purpose of ignition timing is to determine the
right moment for the delivery of the fuel to the
injection nozzles. The required high accuracy of
the start of injection is ensured by the closed-loop
control.

Start of injection - executed functions

The following functions are governed with the
start of injection:

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• Calculation of start of injection on the basis of

characteristic map data
• Correction of the start of injection in the
warm-up phase
• Governing the start of injection during starting
and overrun operation
Start of injection - calculation of charac-
teristic map data
Programmed characteristic maps for the start of
injection serve as a basis for the calculation of the
start of delivery. The actual start of injection is re-
corded by the needle stroke sensor directly at the
nozzle. This measured value is compared with
the map data. The difference causes a change of
the control for the solenoid valve at the injection
timing device. The control is changed until the
system deviation is zero.

1 Engine speed
Start of injection - constant value gover-
2 Fuel mass
ning during the warm-up phase 3 Start of injection
During the starting process and in the warm-up
phase, the start of injection is governed with con-
stant values. The electronic control unit corrects
the start of injection depending on the coolant
temperature. When the coolant temperature
decreases, the start of injection is “retarded”.
Conversely, with increasing engine temperature
the start of injection is “advanced”. This improves
the ignition performance of the fuel at low tempe-
ratures.

Start of injection - when starting the en-

gine
The time of the start of injection during starting
is also governed on the basis of the coolant tem-
perature. The start of injection is advanced to
improve starting.

Start of injection - dynamic check and

adjustment
The dynamic check and corrections of the start
of injection is only possible in the function “basic
setting”.
As a general rule, the start of injection must be
checked and, if necessary, adjusted after the
toothed belt has been replaced and after any
screws at the injection pump or the sprockets
have been unscrewed.

Required special tools

• Torque spanner (5 - 50 Nm)

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• Laptop with software

• Interface cable (diagnostic connector to lap-
top) 300 365 2503

Test and adjustment prerequisites

• Basic mechanical setting of the engine OK
• Toothed belt tension OK
• Operate the engine at lower idle speed

Test procedure
¾ Connect the laptop and diagnostic connector
with interface cable.
¾ Start the diagnostic program“Pathfinder”.
¾ Select the button “Basic setting” in the “Inputs
and outputs” menu.
¾ Follow the prompts given by the software.
¾ Read the example diagram.
The start of injection in the Display field depends
on the fuel temperature in the Display field.

A Display field for start of injection

B Display field for fuel temperature
C Desired range for start of injection

Reading example:
The number 90 in Display field (B) corresponds to
a numerical value ranging from 34 - 73 in Display
field (A).

NOTE

If the start of injection is in the desired range du-

ring the check, no adjustment is necessary. After
repairs like: Injection pump installation and remo-
val, valve timing adjustment, the start of injection
must be set to the mean value of the desired
range.

If the start of injection is outside of the desired

range, adjust the start of injection as follows:
¾ Remove the upper toothed belt guard.

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¾ Loosen the two fastening bolts (1) at the injec-

tion pump sprocket.
¾ Install a 22 mm ring spanner on the hub nut (2)
to hold the pump shaft.

NOTE

Do not loosen the nut (2) for the hub. If so, the
basic adjustment of the injection pump will be
out of adjustment and it can not be adjusted with
workshop tools.

¾ Loosen the third injection pump sprocket fas-

tening bolt and turn the pump shaft slightly:

Anti-clockwise To retard start of injection

Clockwise To advance start of injection

Type A: Fastening bolts machined on shaft and

tip (arrows)

NOTE

The fastening bolt type A may only be used once

as they are anti-fatigue screws.

After the dynamic check of the start of injec-

tion, the fastening bolts must be retightened 90°
(¼ turn).
¾ Tighten the new injection pump sprocket fas-
tening bolts.
Torque: 20 Nm
Type B: Fastening bolts not machined on shaft
and tip

NOTE

Do not replace type B fastening bolts.

¾ Tighten the old injection pump sprocket faste-

ning bolts.
Torque: 25 Nm

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Injection nozzles - two-spring nozzle holder

To reduce the combustion noise to a minimum

and also reduce the mechanical load, a slow
pressure increase in the combustion chamber is
necessary.
Moreover, the fuel should not be injected ab-
ruptly, but continuously over a longer period of
time.
A two-spring nozzle holder was developed for the
1.9-litre BJC engine to make combustion smoo-
ther. With this nozzle fuel injection proceeds in
two steps.

Two-spring nozzle holder - method of

operation
Step 1 (prestroke)
The nozzle holder (2) has two springs of different
strengths. These are adjusted to each other in
such a way that at the beginning of injection the
nozzle needle is lifted against the power of spring
1 (1) only. Initially, only a small quantity of fuel is

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injected at a low pressure (p = 190 bar) through

the gap which arises as a result of stroke 1 (5).
This leads to a smooth pressure increase of the
combustion pressure, thus creating the ignition
conditions for the main fuel quantity.
Step 2 (total stroke)
The injection pump continues to deliver fuel. This
leads to a pressure rise in the injection nozzle,
because the delivered fuel quantity cannot run
off through the small gap. Due to this pressure
rise, the force of spring 2 (3) is overcome and the
nozzle needle (4) is raised by stroke 2 (6) to the
total stroke (7).
The main injection of the residual amount is ef-
fected at a higher injection pressure (p = 220 bar)
through the enlarged gap.

Injection nozzles - check

NOTE

In case the injection nozzles are defective, they

must be replaced since neither a pressure adjus-
tment nor repair is possible.
Required special tools
• Injection nozzle tester with pressure line
VW VAG 1322

Checking the injection pressure

WARNING

During the test, the fuel comes from the nozzle

with high pressure. The fuel jet can penetrate the
skin and cause serious injury.
Never expose parts of the body to the fuel jet.
Wear protective goggles.

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¾ Connect the injection nozzle to the nozzle tes-

ter.
¾ Depress the pump lever slowly. Read the in-
jection pressure at the start of injection.
If the injection pressure deviates from the desired
pressure, replace the injection nozzles.
Desired pressures:

New nozzles: 220 - 230 bar

Wear limit: 200 bar

Nozzle leakage test

¾ Depress the pump lever slowly and hold the
pressure for 10 seconds at approx. 150 bar.
No fuel should leak from the nozzle tip.
¾ In case of leakage, replace the injection
nozzle.

Injection nozzles - removal and instal-

lation
Defective nozzlesare found by loosening injec-
tion line union nuts in succession while the engine
is operated at fast idle speed. The nozzle is de-
fective if the engine speed stays constant after
the union nut is loosened.
Defective injection nozzles cause the following
malfunctions:
• Backfiring
• Knocking in one or more cylinders
• Engine overheated
• Drop in performance
• Excessive black exhaust smoke
• High fuel consumption
• Increased blue smoke during cold start

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Required special tools

• torque wrench 5 - 50 Nm
• ring spanner VW 3035

Injection nozzles - removal

¾ Remove the injection lines with the open ring
spanner VW 3035.
¾ Loosen the fastening screw, remove the clamp
and withdraw the injection nozzle.

Injection nozzles - installation

NOTE

Always replace the protective seals between the

cylinder head and injection nozzles.

¾ Install the injection nozzles.

¾ Pay attention to the correct seat of the bearing
pedestals in the cylinder head.
¾ Fit the clamps.
Tightening torques:

Fuel injection lines: 25 Nm

Screw for clamp: 20 Nm

One-way restrictor
The one-way restrictor (1) is located in the pres-
sure valve of the injection pump. The one-way
restrictor avoids dribbling at the injection nozzle
and the formation of bubbles in the injection line.

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One-way restrictor - return flow function

During the return flow, the valve plate (2) shuts
off the main passage by means of the power of
the compression spring (4). The fuel flows only
through the throttle passage (3). This dampens
an existing pressure wave.

One-way restrictor - fuel supply function

When the fuel is delivered, the valve plate (2)
is lifted up by the pressure of the fuel and the
restrictor has no effect. The fuel flows through
the main passage.

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Injection system - overview

1 Control unit for injection system 0N1 6 Start of injection valve 0Y2
2 Injection nozzle with needle stroke sensor 0B5 7 Fuel shut-off valve 0Y1
3 Intake pipe temperature sending unit 0B4 8 Fuel quantity regulating mechanism of the injec-
4 Coolant temperature sending unit 0B1 tion pump with fuel temperature sending unit 0B3
5 Engine speed sensor 0B2

The control unit of the direct injection unit is has to be carried out before any repairs and
equipped with a fault history. The fault history adjustments and fault finding are carried out.
must be displayed and an actuator diagnosis

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The control unit can detect and store faults when

testing and adjusting. For this reason the fault NOTE
history must be cleared after the completion of
testing and adjusting activities. The following five rules for cleanliness should be
observed when working on the fuel supply/injec-
tion system:
WARNING
If the engine is to be operated at cranking speed • Before disconnecting any connections, clean
without starting the engine (eg for the compres- the junction points and the surrounding area
sion check), fuel can be ejected at the injection thoroughly.
nozzles, causing severe skin injuries. • Put dismantled parts on a clean surface and
Pull the plug off the fuel shut-off valve at the cover them. Use lint-free cloths.
injection pump. • If the repair is not carried out immediately,
cover or seal open components with care.
CAUTION • Install only clean parts. Do not take spare parts
out of the packing before they are actually
Short can occur when testing the injection and
installed. Do not use parts which were stored
preheating systems.
without packing (eg in tool boxes).
Connect/disconnect the preheating and injection
system cables and also the tester leads only with • If the system is open: Do not work with com-
the ignition switched off. pressed air if at all possible. Do not move the
truck if possible.
• Moreover, make sure that no diesel fuel drops
on the coolant hoses. In such a case, the
hoses must be cleaned immediately. Affected
hoses must be replaced.

Injection system - supply voltage check

Required special tools ¾ Connect the test adapter to the control unit
cable loom.
• Test adapter 7 917 299 010
¾ Measure the supply voltages.
• Multimeter
• Wiring diagram If the specified value is not obtained:
¾ Check the voltage supply relay, terminal 30.
Prerequisites for testing
¾ Check the line connections in accordance with
• Battery voltage is correct the circuit diagram for interruption, short circuit
and resistance at the contact points.
Test procedure
If the lines or the relay are not defective:
¾ Turn off the ignition. ¾ Replace the control unit for direct injection
system 0N1.

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Injection pump - removal and installation, toothed belt replacment

1 Bolt (torque 120 Nm) 12 Reflection pulley

2 Bolt (torque: 40 Nm) 13 Bolt (torque 20 Nm)
3 Bolt (torque 15 Nm) 14 Bolt (torque 20 Nm)
4 Bolt (torque 22 Nm) 15 Bolt (torque 20 Nm)
5 Lower toothed belt guard 16 Bolt (torque 45 Nm)
6 Bolt (torque 10 Nm) 17 Camshaft sprocket
7 Middle toothed belt guard 18 Spring-loaded idler pulley
8 Bolt (torque 45 Nm) 19 Reflection pulley
9 Engine mount 20 Injection pump sprocket, bipartite
10 Upper toothed belt guard 21 Bolt (torque 30 Nm)
11 Toothed belt 22 Rear toothed belt guard

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23 Water pump 27 Injection pump

24 Reflection pulley 28 Bracket
25 Toothed belt sprocket on crankshaft 29 Bolt (torque 45 Nm)
26 Bush

Toothed belt - removal and installation,

tightening
Required special tools
• Locating pin VW 3359
• Camshaft setting jig VW T10098
• Nut driver VW V 159
• Torque spanner (5 - 50 Nm)
• Puller VW T40001
• Holding jig 000 941 8014

NOTE

The toothed belt may only be adjusted with the

engine cool.

Toothed belt - removal

¾ Remove the upper toothed belt guard.
¾ Remove the vacuum pump.
¾ Remove the ribbed V-belt.
¾ Turn the crankshaft until the TDC mark on the
flywheel is in line with the mark on the interme-
diate housing.

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¾ Screw the close-tolerance screws (1) into the

cylinder head against the stop by hand.
¾ Lock the camshaft as shown with the camshaft
setting jig VW T10098.

¾ Lock the injection pump sprocket with locating

pin VW 3359.
¾ Loosen the fastening screws (1) of the injection
pump sprocket.

NOTE

Do not loosen the nut (2) for the hub. If so, the
basic adjustment of the injection pump will be
out of adjustment and it can not be adjusted with
workshop tools.

¾ Loosen the idler pulley.

¾ Remove the vibration damper/pulley.
¾ Remove the rear and middle toothed belt gu-
ard.
¾ Mark the running direction of the toothed belt.
¾ Remove the toothed belt.
¾ Check the water pump for wear (see section
“Water pump”)

Toothed belt - installation

¾ Check the TDC mark on the flywheel or carrier
plate. The mark must be aligned with the refe-
rence mark.
¾ Loosen the camshaft sprocket fastening bolt
one turn. Hold the camshaft sprocket faste-
ning bolt with the holding jig 000 941 8014.

NOTE

Never use the camshaft setting jig VW T10098

as holding jig to release and tighten the camshaft
sprocket! Use the holding jig 000 941 8014.

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¾ Position the puller VW T40001 with the single

claw (A) and the double claw (B) centrally on
the camshaft sprocket and pull it off.
¾ Use an open-end spanner (C) as holding jig.
¾ Install the toothed belt on toothed belt sprocket
of the crankshaft, reflection pulley, injection
pump sprocket, water pump sprocket and
spring-loaded idler pulley.
¾ Align the injection pump sprocket in the middle
position in the elongated holes.
¾ Refit the camshaft sprocket together with the
toothed belt and fix with the fastening screw
(camshaft sprocket can still be turned).
¾ Tightening the toothed belt. Turn the nut driver
(eg VW V 159) at the cam clockwise until the
notch and the boss (arrow) are in line.

NOTE
If the cam was once turned too far once, the ten-
sion of the spring-loaded idler pulley must be fully
relieved and retensioned. Do not turn the cam
back by the dimension turned too far.

¾ Tighten the clamping nut on the spring-loaded

idler pulley.
Torque: 20 Nm
¾ Recheck the TDC mark on the flywheel or car-
rier plate.

NOTE

Pay attention to the correct seating of the spring-

loaded idler pulley in the rear toothed belt guard
(arrow).

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¾ Tighten the camshaft sprocket fastening

screw.
Torque: 45 Nm
Fastening bolts for injection pump type A:
Fastening bolts machined on shaft and tip (ar-
rows)
The fastening bolts may be used once only, since
they are anti-fatigue bolts.
¾ Tighten the new injection pump sprocket fas-
tening bolts.
Torque: 25 Nm

NOTE
After the dynamic check of the start of injec-
tion, the fastening bolts must be retightened 90°
(¼ turn).

Fastening bolts for injection pump type B:

Fastening bolts not machined on shaft and tip

NOTE
Do not replace the fastening bolts.

¾ Tighten the old injection pump sprocket faste-

ning bolts.
Torque: 25 Nm
¾ Remove the camshaft setting jig VW T10098
from the camshaft.
¾ Remove the locating pin.
¾ Rotate the crankshaft two turns in the direction
of engine rotation and set to TDC for cylinder 1.
¾ Check the following points:
• the TDC mark on the flywheel or the carrier
plate
• the camshaft setting jig in the camshaft
• the locating pin in the ijection pump sprocket
• the setting of the spring-loaded idler pulley
(notch/boss or notch/arrow)
¾ Start the engine. Let it run for about 10 se-
conds, then stop the engine.
If the notch and boss or notch and arrow are not
in line:
¾ Retighten the spring-loaded idler pulley and
the fastening nut to 20 Nm.

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¾ Rotate the crankshaft two turns in the direction

of engine rotation until the crankshaft is at TDC
for cylinder 1 again.
¾ Repeat the check.
¾ Install the vacuum pump.
Torque: 20 Nm.
¾ Install the toothed belt guard and vibration
damper/pulley.
¾ Install the ribbed V-belt.
¾ Check the start of injection dynamically and, if
necessary, adjust it.

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Injection pump - removal and installation

1 Bolt (torque 20 Nm) 11 Fitting with pressure valve (torque 20 Nm)

2 Injection pump sprocket 12 Screw (torque 25 Nm)
3 Fastening nut 13 Injection nozzle for cylinder 3 with needle lift
4 Outlet - supply line sensor
5 Injection pump 14 Screw (torque 20 Nm)
6 Fuel shut-off valve (torque: 40 Nm) 15 Clamp
7 Inlet - return line 16 Bearing pedestal
8 Return line to control valve/fuel filter 17 Heat shield
9 Screw (torque 25 Nm) 18 Screw (torque 10 Nm)
10 Injection lines 19 Valve for start of injection

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20 Strainer 24 Bush with nut

21 O-ring 25 Bracket
22 Screw (torque 25 Nm) 26 Screw (torque 25 Nm)
23 Cover for injection timing device

Required special tools

• Adapter VW VAG 131810
• Manual vacuum pump VW VAG 1390
• Ring spanner VW 3035

Injection pump - removal

¾ Set the crankshaft to TDC of cylinder 1 (arrow).
¾ Disconnect all fuel lines at the pump.

NOTE

To loosen the injection lines, use the open ended

ring spanner VW 3035.

¾ Remove the toothed belt.

¾ Cover the openings with a clean cloth.

¾ Disconnect the 10-pin connector to the injec-

tion pump (arrow) and remove the plug from
the holder.

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¾ Remove the loosened fastening screws (1) for

the injection pump sprocket.

NOTE

Do not loosen the nut (2) for the hub. If so, the
basic adjustment of the injection pump will be
out of adjustment and it can not be adjusted with
workshop tools.

¾ Remove the fastening screws (1) from the

retainer.

¾ Remove the fastening screw from the rear

support (arrow).
¾ Remove the injection pump.

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Injection pump - installation

¾ Position the injection pump in the compact
holder and fasten the screw to the rear support
with the fastening nut.

NOTE

The fastening screws machined at the threaded

shaft and tip must be replaced. Do not replace
fastening screws not machined on the shaft and
tip.

¾ Insert the fastening screws (1) and tighten the

screws.
Torque: 25 Nm.
¾ Install, tension the toothed belt.
¾ Install the injection lines.
Torque: 25 Nm
¾ Fasten the supply line to the outlet on the injec-
tion pump.
¾ Connect the 10-pin connector to the injection
pump (arrow) and the insert the plug in the
holder.

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Injection pump - filling with fuel

¾ Screw the adapter VW VAG 131810 into the
return line port of the injection pump.
¾ Connect the manual vacuum pump
VW VAG 1322 to the adapter with approx. 1 m
of transparent plastic hose.
¾ Operate the manual vacuum pump until fuel
emerges from the return line port. Do not draw
the fuel into the manual vacuum pump.
¾ Remove the adapter VW VAG 131810 and
install the union with the return line.
Torque: 25 Nm.
¾ Check the start of injection dynamically and, if
necessary, adjust.
¾ Subsequently read out the fault history of the
engine control unit.
¾ If necessary, clear the fault history

Injection pump - pump and toothed

belt adjustment
Toothed belt - overview

Method of operation
The toothed belt drives the
• camshaft
• distributor injection pump
• water pump
The required wrap is brought about by two re-
flection pulleys, the tension is provided by the
semi-automatic spring-loaded idler pulley.

Toothed belt - adjustment

NOTE
There are marks for the adjustment of engine
valve timing (position of crankshaft, camshaft
and injection pump).
1 Reflection pulley
Crankshaft position 2 Injection pump sprocket
3 Reflection pulley
The top dead centre mark for cylinder 1 shows up 4 Sprocket - crankshaft
on the flywheel in the inspection hole of the bell 5 Water pump
housing. 6 Semi-automatic tensioner pulley
7 Camshaft sprocket

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Camshaft position
The correct position is fixed with a new adjusting
ruler. The exact camshaft position is very impor-
tant for precise valve timing when installing the
toothed belt.

Injection pump sprocket

The injection pump is locked with the locating
pin (1). The injection pump sprocket consists
of two parts. A fine adjustment can be made by
loosening the 3 screws (arrow).

NOTE

Do not loosen the nut for the injection pump hub.

This would change the basic setting of the injec-
tion pump. It can not be adjusted with workshop
tools.

The exact procedure is described in the section

“Injection pump - removal and installation, too-
thed belt replacement”.
Cylinder head gasket
The cylinder head gasket is made of metal and is
thus resistant to higher temperatures and pres-
sures.

NOTE
When installing new parts like pistons,
crankshaft, etc. the tolerances must be ta-
ken into consideration with the appropriate
thickness of the cylinder head gasket.

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Engine block
Ribbed V-belt - removal and installa-
tion

Ribbed V-belt - removal

¾ Mark the running direction of the ribbed V-belt.

1 Ribbed V-belt
2 Bolt, torque 10 Nm
3 Pulley of vibration damper
4 Bolt, torque 25 Nm
5 Tensioner
6 Alternator
7 Compact holder for injection pump, three-phase
alternator and vane pump
8 Bolt, torque 45 Nm
9 Banjo bolt, torque 30 Nm
10 Sealing ring
11 Pressure line
12 Steering pump

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¾ Swivel the spring-loaded idler pulley with a

16 mm flat ring spanner at the tensioning lever
in the direction of the arrow

Ribbed V-belt - installation

Installation is carried out in the reverse order of
removal.

NOTE
Before installation of the ribbed V-belt, make sure
the running direction of the belt is correct and it is
properly positioned in the pulleys.

¾ For trucks without air conditioning: Place

ribbed V-belt on alternator last.
¾ On trucks with air conditioning: Place rib-
bed V-belt on A/C compressor last.

Ribbed V-belt - A/C compressor drive belt

routing

NOTE

The car type is depicted. Linde trucks do not have

a vane pump.

1 Pulley vibration damper

2 Spring-loaded idler pulley
3 Alternator pulley
4 Ribbed V-belt
5 Vane pump pulley for power steering

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Ribbed V-belt - drive belt routing with A/C

compressor

1 Pulley vibration damper

2 Spring-loaded idler pulley
3 Alternator pulley
4 Vane pump pulley for power steering
5 Reflection pulley
6 Ribbed V-belt
7 Belt pulley for A/C compressor

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Crankshaft oil seal on pulley end - removal and installation

1 Bolt (torque 15 Nm) 5 Flywheel

2 Sealing ring 6 Bolt (torque 60 Nm)
3 Sealing flange 7 Intermediate plate
4 Cylinder block 8 Sealing flange

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Required special tools

• Guide bush VW 2080 A
• Holding jig VW 3415
• Sealing ring extractor VW 3203
• Clamping sleeve VW 3265
• Mounting device for PTFE design VW T10053
• Torque spanner (5 - 50 Nm)
• Torque spanner (40 - 200 Nm)

Sealing ring - removal

¾ Remove the ribbed V-belt
¾ Remove the toothed belt

¾ Remove the crankshaft sprocket. To do so,

hold the pulley with the holding jig VW 3415.
¾ To guide the seal extractor, screw the cen-
tral screw manually as far as the stop into the
crankshaft.

¾ Turn the internal part of the seal extractor

VW 3203 by two turns (approx. 3 mm) out of
the external part and lock with knurled screw.
¾ Grease the threaded part of the seal extractor
with oil, position the extractor and screw it as
far as possible into the sealing ring, applying
strong pressure.
¾ Loosen the knurled screw and turn the internal
part against the crankshaft until the sealing
ring is pulled out.

Sealing ring - installation

¾ Grease the sealing lip of the sealing ring
slightly with oil.

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¾ Put the guide bush of VW 2080 A onto the

crankshaft journal.
¾ Push the sealing ring over the guide bush.

¾ Use the clamping sleeve VW 3265 to press in

the sealing ring with the central screw as far as
the stop (1).
¾ Installing, tensioning the toothed belt

NOTE

Use of PTFE sealing rings (characteristic: wit-

hout internal hose spring, sealing lip broader). Do
not oil or grease the sealing lip of these seals.An
early-type radial shaft seal (with internal hose
spring) may only be replaced with a PTFE seal,
but not vice versa

Installing the PTFE sealing ring

NOTE

Do not also oil or grease the sealing lip of the seal.

¾ Remove the oil residues on the crankshaft

journal with a clean cloth.
¾ Put the guide bush VW T10053/1 onto the
crankshaft journal.
¾ Push the sealing ring over the guide bush onto
the crankshaft journal.

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¾ Press in the sealing ring with the clamping

sleeve VW T10053 and screw VW T10053/2
as far as the stop.
¾ Installing, tensioning the toothed belt
¾ Install the ribbed V-belt

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Crankshaft sealing flange - removal and installation

1 Bolt (torque 15 Nm) 5 Flywheel

2 Sealing ring 6 Bolt (torque 60 Nm)
3 Sealing flange 7 Intermediate plate
4 Cylinder block 8 Sealing flange

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Required special tools

• Guide bush VW 2080 A
• Holding jig VW 3415
• Torque spanner 5 - 50 Nm
• Torque spanner 40 - 200 Nm
• Power drill with plastic brush insert
• Silicone sealant D 176404 A2
• Blunt scraper

Sealing flange - remove

¾ Remove the ribbed V-belt.
¾ Remove the toothed belt.
¾ Remove the crankshaft sprocket. To do so,
hold the pulley with the holding jig VW 3415.

NOTE
When screwing on the holding jig, put two was-
hers between the sprocket and jig.

¾ Drain the engine oil.

¾ Remove the oil sump.
¾ Unscrew the front sealing flange.
¾ Take the sealing flange off, hitting it lightly, if
necessary, with a rubber mallet.
¾ Remove any sealant residues on the cylinder
block with a blunt scraper.
¾ Remove any sealant residues on the sealing
flange with a rotating plastic brush.

WARNING

The rotating brush loosens particles, which are

flung off at high speed. These particles can cause
eye injuries.
Wear protective glasses!

¾ Clean the mating faces. They must be free

from oil and grease.

Sealing flange - installation

NOTE
Observe the use-by date of the sealant.

Once the silicone sealant has been applied, the

sealing flange must be installed within 5 minutes.

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¾ Cut off the tube nozzle at the front mark (nozzle

diameter approx. 3 mm).
¾ Apply the silicone sealant on the clean mating
face of the oil sump as shown in the figure. The
sealant bead (arrow) must have a thickness of
2 to 3 mm.

CAUTION

Any excess sealant can drop into the oil sump and
clog the screen in the suction line, thus causing
damage to the engine.
The sealant bead should not be thicker than
3 mm.

¾ Apply silicone sealant bead as shown in the fi-

gure on the clean sealing surface of the sealing
flange.
¾ Position the sealing flange immediately and
slightly tighten all screws.

NOTE

To position the sealing flange with the sealing

ring mounted, use the guide bush from WM 298.

¾ Fasten the sealing flange by tightening oppo-

site screws.
Torque: 15 Nm
¾ Install the oil sump.

NOTE

After fitting the oil sump, the sealant must dry for
about 30 minutes. Do not the fill engine oil before
this period is over.

¾ Install the toothed belt and adjust the engine

valve timing.
¾ Install the ribbed V-belt.

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Cylinder head - check

1 Upper toothed belt guard 11 Lift bracket

2 Toothed belt 12 Cylinder head bolt
3 Bolt (torque 20 Nm) 13 Oil barrier
4 Bolt (torque 20 Nm) 14 Cylinder head cover
5 Bolt (torque 45 Nm) 15 Sealing boot
6 Camshaft sprocket 16 Oil filler cap
7 Spring-loaded idler pulley 17 Ventilation tube
8 Reflection pulley 18 Clamp
9 Rear toothed belt guard 19 Pressure control valve
10 Bolt (torque 10 Nm) 20 Seal

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21 Bolt (torque 5 Nm) 25 Injection nozzle

22 Injection lines 26 Glow plug
23 Vacuum pump 27 Cylinder head gasket
24 Seal

Cylinder head - check for flatness

Maximum permissible distortion: 0.1 mm

NOTE

Resurfacing of diesel cylinder heads is not allo-

wed.

Cylinder head - check piston position at

TDC

Required special tools

• Dial gauge holder VW 3827
• Measuring plate VW 38517

Test procedure
When installing a new piston or a partial engine,
the piston position must be checked at TDC.
Depending on the projection of the piston, the ap-
propriate cylinder head gasket must be installed
according to the following table:

Marking
Piston projection Notches/holes/thick-
ness
0.91 mm - 1.00 mm 1 / 1.55 mm
1.01 mm - 1.10 mm 2 / 1.36 mm
1.11 mm - 1.20 mm 3 / 1.71 mm

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Cylinder head - identification

Part No. Arrow 1
Control code Arrow 2 (not required)
Holes Arrow 3

NOTE
If different values are measured when measuring
the piston projection , the largest dimension shall
apply for the selection of the gasket.

Cylinder head - removal and installa-

tion

Cylinder head - removal

Due to the confined conditions, pay special at-
tention to the following when dismantling parts:
Route all kind of lines (eg for fuel, hydraulic sys-
tem oil, coolant and refrigerant, vacuum) and
electrical lines so that the original line routing can
be restored when reassembling.
Make sure there is sufficient clearance to all mo-
veable or hot components.
All cable binders which were loosened or cut
open during removal must be attached at the
same place upon installation.
¾ Disconnect the battery earth lead with the igni-
tion switched off.
¾ Drain the coolant.
¾ Pull off all coolant hoses to the cylinder head
with the spring clamp pliers VAS 5024.
¾ Pull off/disconnect all further electric lines from
the cylinder head as required and put them to
the side.
¾ Pull off the vacuum and vent lines from the
cylinder head.
¾ Remove the upper part of the intake pipe.
¾ Remove the top toothed belt guard, the cylin-
der head cover and the vacuum pump.
¾ Remove the camshaft sprocket.
¾ Loosen the cylinder head bolts. Observe the
correct sequence.

NOTE

Always replace the cylinder head bolts.

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In case of repair, remove sealant residues care-

fully from cylinder head and cylinder block. Take
care not to cause any long scoring or scratches.
If emery paper is used, the grain should not be
under 100. Remove abrasive residues with care.
Do not take the new cylinder head gasket out of
its packing until it is actually mounted. Handle
the new gasket with utmost care. Any damage of
the silicone layer and in the bead area will lead to
leakage.
¾ Put the crankshaft to the TDC mark before
mounting the cylinder head.
¾ Turn the crankshaft against the sense of rota-
tion of the engine until all pistons are almost
uniformly under TDC.
¾ Position the cylinder head gasket.
¾ Put the cylinder head in place, insert the re-
maining cylinder head bolts and tighten them
by hand.

¾ Tighten the cylinder head bolts in four stages

in the order shown in the figure as follows:
1. Initial tightening with torque wrench

Stage 1 40 Nm
Stage 2 60 Nm

2. Continue tightening with a rigid spanner

Stage 3 ¼ turn (90°)

Stage 4 ¼ turn (90°)

NOTE

Note: The cylinder head bolts do not need to be

tightened after repairs.

¾ After tightening the cylinder head, turn the

camshaft sprocket so that the cams for cylinder
1 face upwards at the same angle. Before
installing the toothed belt, set the crankshaft to
TDC by rotating the engine in the direction of
rotation.

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Cylinder head - compression check

Required special tools
• Flexible head spanner VW 3220
• Torque spanner 5 - 50 Nm
• Adapter VW VAG 138112
• Tester for compression VW VAG 1763

Test prerequisite
Engine oil temperature at least 30°C

Test procedure
¾ Disconnect the 10-pin connector to the quan-
tity regulating mechanism of the injection
pump.
¾ Remove all glow plugs with the flexible head
spanner VW 3220.
¾ Screw in the adapter VW VAG 138112 instead
of the glow plugs.
¾ Check the compression with tester
VW VAG 1763.

NOTE

For tester handling, refer to the tester operating

instructions.

¾ Actuate the starter until the tester no longer

indicates a rise in pressure.

Compression readings
New 25 - 31 bar
Wear limit 19 bar

Admissible difference between all cylinders:

5 bar
¾ Install the glow plugs with the flexible head
spanner VW 3220.
Tightening torque: 15 Nm.
¾ Display the fault history
¾ Clear the fault history, if necessary

NOTE

Disconnecting the connectors to the injection

pump causes faults to be stored.

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Valve gear

1 Bearing cap 7 Valve spring

2 Screw (tightening torque 20 Nm) 8 Valve stem seal
3 Camshaft 9 Valve guide
4 Tappet 10 Sealing ring
5 Valve keepers 11 Cylinder head
6 Valve spring seat 12 Valve

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Required special tools

• Mounting device VW 2036
• Pulling unit VW 3047
• Valve stem seal installer VW 3129
• Mounting lever VW 5411 A

Dismantle valve stem seal

(with cylinder head installed)
¾ Remove camshaft.
¾ Take tappet out and put it down with the run-
ning surface pointing downwards. Make sure
that the tappets are not mixed up.
¾ Put the piston of the respective cylinder to the
top dead centre (TDC).
¾ Use mounting device VW 2036 and adjust the
bearing to stud height.
¾ Dismantle valve springs using mounting lever
VW 5411 A.

NOTE

During this procedure, the valves are supported

on the piston bottom.

¾ Pull off the valve stem seals with the VW 3047.

Install valve stem seal

¾ Plug the supplied plastic bushing into the cor-
responding valve stem. This prevents damage
to the new valve stem seal.

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¾ Insert the new valve stem seal into the valve

stem seal installer VW 3129.
¾ Grease the sealing lip of the valve stem seal
with oil and push it carefully onto the valve
guide.

Oil sump - removal and installation

Required special tools

• Power drill with plastic brush insert
• Silicone sealant D 176404 A2
• Blunt scraper

Oil sump - removal

¾ Drain the engine oil.
¾ Remove the oil sump.
If necessary, loosen the oil sump by hitting it
lightly with a rubber mallet.
¾ Remove any sealant residues on the cylinder
block with a blunt scraper.
¾ Remove any sealant residues on the oil sump
with a rotating brush, eg a power drill with plas-
tic brush insert

WARNING

The rotating brush loosens particles, which are

flung off at high speed. These particles can cause
eye injury
Wear protective goggles!

¾ Clean the mating faces.

They must be free from oil and grease.

Oil sump - installation

NOTE

Observe the use-by date of the sealant.

Once the silicone sealant has been applied, the

oil sump must be installed within 5 minutes.

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¾ Cut off the tube nozzle at the front mark (nozzle

diameter approx. 3 mm).
¾ Apply the silicone sealant on the clean mating
face of the oil sump as shown in the figure.
The sealant bead should have a thickness of
2 - 3 mm and run around the screw holes on the
inside (arrows).

CAUTION

The sealant bead should not be thicker as excess

sealant can drop into the oil sump and clog the
screen in the suction line.
The sealant bead should not be thicker than
3 mm.
¾ Apply the silicone sealant on the clean mating
face of the oil sump as shown in the figure (the
figure shows the position of the sealant bead
on the cylinder block).
¾ Install the oil sump immediately and slightly
tighten all screws.
The oil sump must be flush with the cylinder block.
¾ Tighten the oil pan screws to a torque of 15 Nm.

NOTE

After fitting the oil sump, the sealant must dry for
about 30 minutes. Do not fill the engine oil before
this period is over.

The rest of the installation is done in the reverse

order of removal.

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Hydraulic bucket tappets - check

1 Bolt, torque 45 Nm 9 Collets

2 Camshaft sprocket 10 Upper valve spring seat
3 Sealing ring 11 Valve spring
4 12 Valve stem seal
5 Hexagonal nut, torque 5 Nm 13 Valve guide
6 Bearing caps 14 Cylinder head
7 Camshaft 15 Valve
8 Bucket tappets

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Assembly notes
¾ Item 1: Use holding jig VW 3415 for loosening
and tightening.
¾ Item 6: Coat mating face of bearing cap 1
lightly with sealant AMV 174 004 01.
¾ Item 8: Do not interchange, with hydraulic
valve clearance compensation, lubricate the
running surface with oil.

Required special tools

• Feeler gauge
• Wooden orplastic wedge

Test procedure

NOTE
Only replace bucket tappets as a complete as-
sembly. They can not be adjusted or repaired.
Irregular valve noises when starting the engine
are normal.

¾ Start the engine and let it run until the engine

oil temperature has reached at least 80 °C.
¾ Increase engine speed to approx. 2500 rpm
for 2 minutes.
If the hydraulic bucket tappets are still noisy, lo-
cate the defective tappet as follows:
¾ Remove the cylinder head cover.
¾ Rotate the crankshaft clockwise until the cam
of the bucket tappet to be checked is pointing
upwards.
¾ Determine the clearance between the cam and
bucket tappet.
If the clearance exceeds 0.1 mm, replace the
bucket tappet.
If the clearance is less than 0.1 mm or no clea-
rance is detected, repeat the test as follows:

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¾ Press the bucket tappet down with a wooden

or plastic wedge.
If free travel in excess of 0.1 mm is felt until the
valve opens:
¾ replace the tappet.

CAUTION
The hydraulic compensation elements must
settle, otherwise the valves can strike the pis-
tons and bend.
Do not start the engine for approx. 30 minutes
after installing new bucket tappets!

Camshaft - removal and installation

Required special tools
• Locating pin VW 3415
• Holding jig 000 941 8014
• Camshaft setting jig VW T10098
• Puller VW T40001
• Nut driver VW V 159

Camshaft - removal
¾ Relieve the toothed belt tension and take it off
the camshaft and injection pump sprockets.

NOTE

The vibration damper/pulley and the middle and

lower toothed belt guard can remain in place.

¾ Remove the camshaft sprocket.

¾ First remove bearing cap 5, 1 and 3. Loosen
opposite bearing caps 2 and 4 alternately.
Camshaft - installation

NOTE
When installing the camshaft, the cams for cylin-
der 1 must be pointing upwards. When installing
the bearing caps, be sure the drilled holes are
aligned; before installation, position the bearing
caps and determine the fitting position.

¾ Coat the running surfaces of the camshaft with

oil.
¾ Tighten opposite bearing caps 2 and 4 alterna-
tely to a torque of 20 Nm.

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¾ Install bearing caps 5, 1 and 3 and also torque

to 20 Nm.
¾ Fit the bearing caps by tapping lightly on the
end of the camshaft.
¾ Fit the camshaft sprocket.
¾ Install, tension the toothed belt.

CAUTION

The hydraulic compensation elements must

settle, otherwise the valves can strike the pis-
tons and bend.
Do not start the engine for approx. 30 minutes
after installing new bucket tappets!

Vacuum pump
The vacuum pump, which is also required in the
diesel engine to create a vacuum, is directly dri-
ven by the camshaft. The vacuum pump consists
of a rotor and an impeller. The impeller is made
of plastic and is moveably mounted.

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Space expansion function

During a rotation of the rotor (2) the impeller (3)
is pressed outwards and the space is expanded.
The space fills with air and, as a result, a vacuum
is created at the air inlet (1).This vacuum is used
by the turbocharger control mechanism and the
exhaust gas recirculation (EGR) valve.

Function: Space narrowing

Due to the continued movement of the rotor and
the impeller, the created space becomes smaller
again. In this way the intake air is compressed
and blown off through the air outlet (4) to the cy-
linder head. At the same time, a new space is
created at the top.

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Mass air flow sensor 0B6

The purpose of the mass air flow sensor is to
determine the amount of fresh air supplied to the
engine. The mass air flow sensor 0B6 is mounted
in the intake pipe directly behind the air filter. It
measures the mass air flow with a hot film sensor
(1).
.The hot film is heated with 12 V. The passing
intake air cools the surface of the hot film. This
cooling lowers the resistance of the hot film. The
electronic control unit evaluates the drop in vol-
tage caused by the change in resistance as the
equivalent for the temperature and quantity of air
taken in.

Signal evaluation
The measuring result of the mass air flow sensor
is the basis for the control of the percentage of
recirculated exhaust gas to be added and the
maximum quantity of fuel to be injected.
A smoke map stored in the control unit limits the
amount of fuel injected if the mass air flow is too
small for smokeless combustion.

Substitute function
In the event of a failure, the charge pressure limit
is reduced and constant values are specified for
the optimum operation of the engine in various
load ranges. The engine power is reduced as a
result.

Mass air flow sensor - check

The mass air flow sensor signal is required by
the control unit for the calculation of the permis-
sible injection rate and for controlling the exhaust
gas recirculation. The smaller the signal from the
mass air flow sensor, the less fuel may be injec-
ted.

Required special tools

• Test adapter 7 917 299 010
• Wiring diagram
• Laptop with software

Prerequisites for testing

• Fuses must be OK.
• The battery voltage must be at least 11.5 V.
• All electric loads must be switched off.

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• Earth connections are OK.

• The fault history must be cleared.

Test procedure
¾ Connect the laptop and start the software.
¾ “Select inputs and outputs”, “Data blocks”,
“Group 10”. The engine must be running at
idle speed
¾ Check the mass air flow in the Display field.
Desired air flow: 380 - 600 mg/stroke.
If the desired air flow is not obtained:
¾ Check the exhaust gas routing.
If the desired air flow is obtained:
¾ Repeat the test. Increase the engine speed of
approx. 1500 rpm under full load to maximum
speed.
¾ Check the desired value of the mass air flow
sensor (mass air intake) in the Display field.
Desired air flow: 700 - 1050 mg/stroke.
¾ End the communication between the vehicle
and laptop.
¾ Turn off the ignition.
If the desired air flow is not obtained:
¾ Replace the mass air flow sensor 0B6.
¾ Subsequently read out the fault history of the
engine control unit and clear the fault history.
If a constant value of 550 mg/stroke is shown in
the Display field:
¾ Disconnect the 5-pin plug from the mass air
flow sensor 0B6.
¾ Turn on the ignition.

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¾ Measure the supply voltage for the mass air

flow sensor between the following contacts of
the plug:

Contact in
Desired value
plug 0B6
2 + earth approx. battery voltage
2+3 approx. battery voltage
4 + earth approx. 5 Volt
4 +3 approx. 5 Volt

If the desired values are not obtained:

¾ Turn off the ignition.

¾ Connect the test adapter 7 917 299 010 to the

control unit cable loom. This does not connect
the control unit.

¾ Using the wiring diagram, check the lines bet-

ween the test box and the plug for interrupti-
ons.
• Contact 2 + socket 1
• Contact 2 + socket 2
• Contact 3 + socket 49
• Contact 4 + socket 30
• Contact 5 + socket 68
Cable resistance: maximum 1.5
¾ Also check the lines for line-to-line shorts,
short to battery earth/engine earth and to bat-
tery positive.
Desired resistance: 8
If no fault is detected in the lines:
¾ Replace the control unit for the direct diesel
injection system 0N1.

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Solenoid valve for charge pressure

limitation 0Y4
The solenoid valve limits the actual charge pres-
sure depending on the values supplied by elec-
tronic control unit.
The load cell of the mechanical charge pressure
control valve is activated.
In the home position the charge air (3) can pass
through the valve with suction pipe pressure.
In the activated state, a part of the charge air is
drawn off to the inlet port (1)

Solenoid valve - control

The electronic control unit sends signals to the
solenoid valve corresponding to the charge pres-
sure map. By opening or closing the valve as
required, either a higher or lower intake pipe
pressure is applied to the charge pressure cont-
rol valve of the turbocharger.

Solenoid valve - substitute function

In case of a failure, the excess pressure is limited
to 0.75 bar by the mechanical governor. 1 To inlet port
2 To mechanical charge pressure valve
Solenoid valve - self-test 3 Intake pipe pressure

A malfunction of the solenoid valve for charge

pressure limitation 0Y4 is not stored by the elec-
tronic control unit. A malfunction of the charge
pressure control, however, is stored. The correct
operation can be checked in the actuator diagno-
sis.

Solenoid valve - resistance check

¾ Disconnect the 2-pin plug from the solenoid
valve for charge pressure limitation 0Y4.

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¾ Connect the multimeter for the resistance test

to the contacts of the valve.
Desired resistance: 14.0 - 20.0

NOTE

At room temperature the resistance is in the lower

tolerance range, at operating temperature in the
upper tolerance range.

If the desired resistance is not obtained:

¾ Replace the solenoid valve for boost pressure
limitation 0Y4.
¾ Subsequently interrogate the fault history of
the engine control unit and, if necessary, clear
the fault history.
If the desired resistance is obtained, check the
supply voltage.

Solenoid valve - supply voltage check

¾ Connect the multimeter to contact 1 of the plug
and to engine earth for the voltage test.
¾ Turn on the ignition.
Desired voltage: at least 11.5 Volt
If the minimum voltage is not obtained:
¾ Check the voltage supply relay termi-
nal 30 (0K2) using the wiring diagram-
¾ Using the wiring diagram, check line con-
nections for interruptions, shorts and contact
resistances at the contact points.
If the minimum voltage is obtained:

¾ Connect the test adapter to the cable loom of

the engine control unit. This does not connect
the control unit.
¾ Using the wiring diagram, check the lines bet-
ween the test box and the plug for interrupti-
ons.Desired value:
• Contact 1 + socket 1
• Contact 2 + socket 2
• Contact 2 + socket 62
Line resistance: max 1.5
¾ Also check the lines for line-to-line shorts,
short to battery earth/engine earth and to bat-
tery positive.
Desired resistance: 8
If no fault is detected in the lines:

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¾ Replace the control unit for direct injection

system 0N1.

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Charge air system with turbocharger

1 Air filter 6 Check valve

2 Turbocharger 7 Main silencer
3 Load cell for charge pressure control 8 Vacuum pump
4 Solenoid valve for charge pressure control (0Y4) 9 Engine VW
5 Accumulator 10 Charge cooler

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Assembly notes

1 Exhaust manifold with turbocharger 12 From air filter

2 Intake pipe 13 Gasket
3 Intake air 14 Gasket
4 Gasket 15 Oil return line to cylinder block
5 Torque: 25 Nm 16 Banjo bolt, torque 40 Nm
6 Gasket 17 Torque: 15 Nm
7 Holder for heat shield, item 9 18 Torque: 40 Nm
8 Washer 19 Bracket
9 Heat shield 20 Torque: 25 Nm
10 Turbocharger 21 Gasket
11 Load cell for charge pressure control 22 Exhaust pipe, front

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23 Union, torque 30 Nm 25 Oil supply line, 22 Nm

24 Torque: 10 Nm

• Item 4: Coating (bead) to intake pipe. Test procedure

• Item 6: Observe mounting position.
¾ Connect the laptop, start the software and
• Item 10: Replace only together with exhaust select “Standardised data blocks”. The engine
manifold. must be idling.
• Item 11: Part of turbocharger, cannot be
¾ “Group 11”.
replaced.
• Item 23: Apply “G 052 112 A3” to thread and ¾ Increase the engine speed of approx.
head mating face. 1500 rpm under full load to maximum speed.
• Item 25: Before installation, fill turbocharger at ¾ Check the desired value for charge pressure
union of oil feeder line with engine oil. (actual) in the Display field.
Desired value: 1600...2100 mbar.
Boost pressure control - check
¾ Terminate the communication between the
Required special tools vehicle and laptop.
¾ Turn off the ignition.
If the desired value is not obtained:
¾ Carry out an actuator diagnosis and activate
the solenoid valve for charge pressure limita-
tion.
The solenoid valve must click and the linkage of
• Manual vacuum pump VAG 1390 the load cell for charge pressure control at the
turbocharger must move to and fro. The linkage
• Hose clamp pliers VAS 5024
must move to and fro at least 3 to 4 times, as long
• Multimeter as a vacuum is present in the vacuum reservoir.
• Test adapter 7 917 299 010
• Wiring diagram NOTE
• Laptop with software
The clicking of the valve cannot be heard due
Prerequisites for testing to the engine noise and can therefore only be
checked by touch.
• Fuses must be OK.
• The battery voltage must be at least 11.5 V. ¾ Continue and finish the actuator test.
• All electric loads must be switched off. ¾ Turn off the ignition.
• Earth connections are OK. If the linkage moves and the desired value for the
• No leaks either on inlet side or on exhaust gas charge pressure (actual) is not obtained:
side.
¾ Turbocharger defective, replace turbocharger.
• Engine oil temperature at least 80 °C.
If the linkage does not move because the sole-
• No problems in engine/injection system
noid valve is not working:
such as start of injection, injection nozzles,
compression. ¾ Checking the solenoid valve for charge pres-
• No fault should be stored in the fault history. sure limitation 0Y4.
Check the fault history ¾ Check the vacuum hoses.
If the linkage does not move although the sole-
noid valve works:

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¾ Connect the manual vacuum pump VAG 1390 If the linkage cannot move freely:
with the load cell for charge pressure control
¾ Turbocharger defective, replace turbocharger.
and check the linkage for ease of movement.
Turbocharger - replacement

NOTE

Observe safety measures. Observe the rules for

cleanliness.

• Hose connections are secured with spring

clamps. In case of repair, only spring clamps
should be used.
• The charge air system must be tight.
• Replace self-locking nuts.

Cooling
Coolant thermostat - removal and
installation
Required special tools
• Hose clamp pliers VW VAS 5024

Coolant thermostat - removal

¾ Drain the coolant.
¾ Remove the coolant hose from the union (2).

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¾ Remove the fastening screws (1) of the union

(2) and take off the union (2) with the coolant
thermostat (4).
¾ Turn the coolant thermostat (4) ¼ turn (90°) to
the left and withdraw it from the union (2).

Coolant thermostat - installation

The installation is in the reverse order of removal.
Please observe the following instructions:
¾ Coat a new O-ring (3) with coolant.
¾ Insert the coolant thermostat (4) in the union
(2) and turn it ¼ turn (90°) to the right.

NOTE
The backets of the coolant thermostat must be
nearly vertical.

¾ Install the union (2) with the coolant thermostat

(4) into the engine block.
¾ Tighten the fastening screws (1).
Torque: 15 Nm
¾ Top up coolant.

Water pump - removal and installation

• Torque spanner 5 - 50 Nm
• Pliers for spring clamps VW VAS 5024
• Antifreeze tester

Water pump - removal

NOTE

Always renew seals and sealing rings.

The lower toothed belt guard does not have to be

removed.
The toothed belt remains in place on the
crankshaft sprocket.
Before removing the water pump, cover the too-
thed belt with a cloth to protect it from the coolant.
¾ Drain the coolant.
¾ Remove the ribbed V-belt.
¾ Remove the toothed belt guard.
¾ Remove the toothed belt from the camshaft
sprocket, injection pump sprocket and water
pump.

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¾ Screw out the fastening bolt (1) from the re-

flection pulley (2) and push it down approx.
30 mm.
¾ Remove the water pump fastening bolts (3)
and carefully withdraw the water pump (4) from
between the engine mount and rear toothed
belt guard.

Water pump - installation

The installation is carried out in the reverse order
of removal. The following must be observed:

¾ Coat a new O-ring (5) with coolant.

¾ Place the water pump (4) in the cylinder block
and tighten the fastening bolts (3).
Torque: 15 Nm

NOTE

The sealing plug on the water pump shows down-

wards.

¾ Install the reflection pulley (2) and tighten the

fastening bolt (1) (replace).
Torque: 40 Nm and ¼ turn (90°).
¾ Install, tension the toothed belt.
¾ Install the ribbed V-belt.
¾ Top up coolant.

Water pump - check wear

Required special tools

• Straight edge
• Feeler gauge

Water pump - check

¾ Turn drive wheel by hand.
The movement should not be sluggish, nor
should there be too much play in the bearing.

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¾ Use the straight edge and feeler gauge to de-

termine the wear (1) along the tooth length.
If the wear exceeds 0.30 mm, the water pump
must be replaced.
Always replace together with the crankshaft pi-
nion.

Coolant - draining and filling

Required special tools
• Pliers for spring clamps VW VAS 5024
• Antifreeze tester

Coolant - draining

WARNING

When the expansion reservoir is opened, hot

steam may escape, causing severe scalding.
Cover the cap with a cloth and open it carefully!

¾ Open the sealing cap of the coolant expansion

reservoir.
¾ Use the pliers for spring band clamps
VW VAS 5024 to pull off the lower coolant
hose at the radiator.
¾ To drain the coolant from the engine also re-
move the connecting piece with the coolant
regulator (arrows).

NOTE

Please observe the regulations for discarding

coolant!

Coolant - filling

NOTE
• Only use G 12 acc. to TL VW 774 D as coolant
additive. Characteristic feature: red colour.
• Never mix G 12 with other coolant additives.
If the fluid in the recovery tank is brown, G 12

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was mixed with an other coolant. In this case

the coolant must be changed.
• G 12 and coolant additives with the note “in ac-
cordance with TL VW 774 D” prevent damage
caused by frost and corrosion, lime deposits
and also raise the boiling temperature. For
these reasons, the cooling system should
always be filled with antifreeze and anti-corro-
sion agent all the year round.
• Especially in countries with a tropical climate,
the coolant contributes, due its higher boiling
point, to operational reliability at high engine
loads.
• The antifreeze protection must be guaranteed
down to approx. -25 °C (in countries with Arctic
climate down to approx. -35 °C.
• Even during the warm season and in warm
countries, never reduce the concentration of
the coolant by adding water. The coolant addi-
tive portion should be at least 40 %.
• If, for climatic reasons, a stronger frost pro-
tection is required, the amount of G 12 can be
increased, but only up to 60 % (frost protec-
tion down to approx. -40 °C), since this would
reduce the frost protection again and also the
cooling effect.
• If the radiator, heat exchanger, cylinder head
or cylinder head gasket were replaced, do not
reuse the coolant.

Recommended mixing ratio:

Percentage of
Frost protection to G 123 Water4
antifreeze
-25°C 40 % 2.4 L 3.6 L
-35°C 50 % 3.0 L 3.0 L

¾ Close the coolant drain plug.

¾ Fill in coolant up to the maximum mark on the
expansion reservoir.
¾ Close the expansion reservoir.
¾ Run the engine until the fan starts operating.
¾ Check the coolant level, adding coolant if ne-
cessary.
When the engine is at operating temperature, the
coolant level must be at the max mark; when the
engine is cold, it must be between the min and
max mark.

3 The coolant quantity may vary depending on the truck equipment.

4 The coolant quantity may vary depending on the truck equipment.

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Engine electrical system

Alternator
To exchange the three-phase alternator, the
freewheel pulley must be removed and installed
again.

Freewheel pulley - removal and installa-

tion
Required special tool
• Polygon head adapter 000 941 8015

Freewheel pulley - removal

¾ Remove the ribbed V-belt.
¾ Remove the protective cap on the freewheel
pulley.
¾ Put the hexagon socket (6 mm) on the drives-
haft of the three-phase alternator.

¾ Support the polygon head adapter

000 941 8015 17 with a ring spanner (17 mm)
and release freewheel pulley by turning
the driveshaft of the three-phase alternator
anticlockwise.

Freewheel pulley - Installing

¾ Insert the polygon head adapter 000 941 8015
in the freewheel pulley.
¾ Screw the freewheel pulley - at first manually
- against the stop onto the driveshaft of the
three-phase alternator.
¾ Support the polygon head adapter
000 941 8015 with a ring spanner (17 mm)
and tighten freewheel pulley by turning the
three-phase alternator anticlockwise with the
torque wrench.
Tightening torque: 80 Nm
¾ Refit the protective cap on freewheel pulley.
¾ Install the ribbed V-belt.

Terminal DFM on three-phase alternator

The signal at terminal DFM is only evaluated in
connection with the auxiliary heater. The signal
for free charging capacity is applied to alternator
terminal DFM.

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Self-test
Lack of plausibility or interruption are stored as
possible error causes.

Terminal DFM - additional signal

Contact 38 at controller 0N1
The DFM line connects the electronic control
unit 0N1 with the combined processor in which
the electronic immobilizer 0N2 (terminal W) is
integrated. The immobilizer signal is transmitted
over this cable. After each replacement of the
control unit the new code must be read into the
combined processor.

Self-test
The electronic control unit detects the interruption
of this line. The engine can no longer be started
in this case.

Replacing the engine control unit / immobilizer

Immobilizer - malfunctions
NOTE
The engine starts, but goes off again after about
1 second. In addition, the engine warning light An immobilizer can only be replaced by a new
comes. This can last up to 30 seconds. type of immobilizer.

Prerequisites Engine control unit - replacement

• Voltage supply correct If the engine control unit is damaged or was

stolen, the immobilizer and engine control unit
• Test adapter cable OK
must be replaced. It is not possible to adapt
• Valid wiring diagram and repair instructions the new engine control unit to an early type of
available immobilizer because the new engine control unit
sends a new code to the early-type immobilizer.
Cause of fault This new code does not correspond with the
previously agreed code of the immobilizer. The
Error code 17978 “Engine control unit disabled”
immobilizer does not recognize the new engine
is stored in the fault history, ie the immobilizer has
control unit and therefore does not respond
not enabled the engine control unit
Adaptation possibilities
Correction
Engine
Immobilizer Adaptation
Replacement of immobilizer control unit
New New Possible
Immobilizer - replacement New Old Not possible
A defective immobilizer has to be replaced. In an Old New Possible
immobilizing system of the third generation, the
immobilizer has an automatic engine control unit
recognition feature. Encoding the control unit is
not necessary.

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Engine require a diagnostic unit after installation for ad-

Immobilizer Adaptation
control unit justments. Both units automatically recognize
Not possible if each other when they are first put into operation
taken from after replacement. The user only has to switch on
Old Old the ignition, and the immobilizer is automatically
different
trucks adapted to the engine control.
Possible if
taken from NOTE
Old Old
different
trucks The immobilizer can only be adapted once. After
the engine control unit has been replaced, the
After one or both control units have been re- start-up has to be performed by the diagnostic
placed, make sure that the immobilizer and the software.
engine control unit are correctly connected with
each other to enable communication. The im-
mobilizer solution for industrial engines does not

Self-test
Self-test - introduction

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Self-test and safety concept of the diesel Level 3: If the operator can no longer influence
engine with Electronic Diesel Control the power output of the engine with the accelera-
“EDC” tor, the EDC lets the engine run at idling speed.
In this way the truck can be moved out of rolling
During operation, the control unit has the follo- traffic.
wing functions:
Level 4: If a safe operation of the engine is no
• Comparison of the readings supplied by longer ensured, the engine is stopped by the
sensors for plausibility. quantity regulating mechanism. If this is not
• Monitoring of the electric and mechanical possible due to the fault, the engine is stopped
working order of the actuators. This is done with the fuel shut-off valve (double safety).
with a comparison of desired values and actual The control unit for the injection system has a
values (variance comparison). The results permanent fault history. This allows a check of
must meet the specified requirements. faults which occurred at earlier starts. This allows
• Monitoring of the state of the cable connectors a quick detection of the causes for problems. The
and connections for interruption and shorts. self-test of the electronic engine control unit is
If faults occur in the system, the EDC responds in carried out in operating mode “1 - Vehicle system
stages, depending on the significance of the fault: test”. The evaluation is carried out with the laptop.
All sensors/actuators are monitored.
Level 1: In the event of sensors with corrective
functions failing, the control continues to operate Starting the diagnosis
with default values or evaluable data from other
sensors. The operator does not notice this gene- ¾ Connect the laptop with the interface converter
rally and it is only detected during maintenance. cable (300 365 2503) on the 7-pin truck
diagnostic connector (6X2).
Level 2: Important faults involving the failure of
subfunctions lead to a drop in performance. The ¾ Ignition “ON”.
operator is warned by the flashing preheating ¾ Start the diagnostic program“Pathfinder”.
time indicator light.

Self-test - fault finding

Required special tools

• Laptop
• Interface converter cable 300 365 2503
• Diagnostic program “Pathfinder”
• Test adapter 7 917 299 010

Prerequisites for testing

• Fuse F12 (2 A) is okay
• The battery voltage must be at least 11.5 V.
• Earth connections between engine and truck
frame okay

Test procedure
¾ Connect the laptop computer.
¾ Connect the diagnostic cable to the diagnostic
connector 6X2 (central electrical system, at
the bottom left looking towards the forks).
¾ Start the diagnostic program.

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Depending on the desired function, you must:

¾ switch on the ignition
or
¾ start the engine,
¾ follow the instructions of the diagnostic pro-
gram.
After the repair, always read out the fault history
of the engine control unit and clear its contents,
check any other stored faults and eliminate and
clear them, if possible.

NOTE

Distinction between “static” and “sporadic” faults.

Static faults: A fault is recognized as static if it
is active for at least 2 seconds. If a static fault
does not occur again within 2 minutes after the
beginning of a driving cycle (ignition is on for at
least 2 seconds), it is stored as sporadic. Spo-
radic fault: If a sporadic fault does not reoccur
during 50 driving cycles (ignition is on for at least
2 seconds), it will be cleared. Before replacement
of the components which have been detected to
be defective, first check the lines and connectors
to these components and the earth connections
in accordance with the wiring diagram. Check
the connectors for correct latching and correct
seating on the relay plate.

Possible causes of faults

NOTE

Check the engine control unit before testing.If a

test of the engine control unit is possible, it may
be assumed that the lines and connections are
okay.

Problem Possible cause Correction

Control unit does not respond Supply voltage too low Check supply voltage and
correct, if necessary (terminal
15 to immobilizer and engine
control)
Short between the cables Check connector and correct the
of 5-pin connector (“W” and fault, if necessary, according to
“K” at the control unit for the the wiring diagram.
immobilizer or short circuit to
earth)
Control unit does not respond Cable defective Check and replace the cable, if
necessary
Immobilizer defective Replace the immobilizer
Control unit defective Replace the control unit

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The control unit identification is automatically

checked after ignition “ON”.

Fault table
The fault table is arranged in the order of the
5-digit fault code number shown on the left
(eg 16500). If components are indicated to be
defective:
• Check the lines and connectors to these com-
ponents.
• Check the earth connections according to the
wiring diagram.
Only replace the component if this check does
not reveal any faults. This applies in particular to
faults reported as “sporadic”.

Possible
Fault code Possible effect Correction
cause
16485
Mass air flow sensor Line interruption or Reduced power Check 0B6 (see
0B6 line-to-earth short Black smoke section “Checking
circuit the components and
Implausible signal 0B6 defective functions”)
16500
Coolant temperature
sending unit 0B1
Implausible signal Line interruption or Black smoke at start Check 0B1
line-to-positive short
circuit
0B1 defective A preheating of about Check coolant regulator
20 s is always carried (see section “Checking
out. the components and
functions”)
16684
Misfires detected
16685
Cylinder 1 misfires
detected
16686
Cylinder 2 misfires
detected
16687
Cylinder 3 misfires
detected
16688
Cylinder 4 misfires
detected
16705
Engine speed sensor
0B2

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Possible
Fault code Possible effect Correction
cause
Implausible signal Line interruption or Engine can stall Check 0B2 (see
line-to-earth short section “Checking
circuit the components and
0B2 defective Engine runs erratically functions”)
Metal chips at 0B2 Indicator light for
preheating time flashes
0B2 loose Higher emission values
Gap between speed
sensor/sensor wheel
too big
16706
Engine speed sensor
0B2
No signal Line interruption or line Engine does not start Check 0B2 (see
short circuit section “Checking
0B2 defective Engine stalls the components and
Indicator light for functions”)
preheating time flashes
16985
Control unit 0N1 Control unit 0N1 Poor driving Replace 0N1 (see
defective internally defective characteristics section “Checking
Engine stop the components and
functions ”)
16989
Control unit 0N1 Control unit 0N1 Poor driving Replace 0N1 (see
defective internally defective characteristics section “Checking
the components and
functions ”)
Engine stop
16990
Control unit 0N1 Control unit 0N1 Poor driving Replace 0N1 (see
defective internally defective characteristics section “Checking
Engine stop the components and
functions ”)
17568
Intake pipe temperature
sending unit 0B4
Short circuit to earth Line-to-earth short Goes to default value Check 0B4 (see
circuit 136.8°C section “Checking
0B4 defective the components and
functions ”)
17569
Intake pipe temperature
sending unit 0B4
Interruption/short circuit Line interruption or Goes to specified value Check 0B4 (see
to positive line-to-positive short 136.8°C section “Checking
circuit the components and
0B4 defective functions ”)

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Possible
Fault code Possible effect Correction
cause
17570
Fuel temperature
sending unit 0B3
Short circuit to earth Line interruption or Goes to specified value Check 0B3 (see
line-to-positive short 136.8°C section “Checking
circuit the components and
functions ”)
17571
Fuel temperature
sending unit 0B3
Interruption/short circuit Line interruption or Goes to specified value Check 0B3 (see
to positive line-to-positive short -5.4°C section “Checking
circuit Higher emission values the components and
functions ”)
17656
Start of injection control
System deviation Fuel tank empty Engine runs erratically Fuel filter or fuel line
clogged
Fuel supply defective, Reduced power Dynamically check and
lack of fuel adjust start of injection
Start of delivery not Higher emission values Check 0Y2, actuator
correct diagnosis
Start of injection valve Poor cold start Check 0B5 (see
0Y2 defective behaviour section “Checking
Needle stroke sensor the components and
0B5 defective functions ”)
17659
Start of injection valve
0Y2
Short circuit to positive Line-to-positive short Engine knocks at check 0Y2 (see
circuit idle because start of section “Checking
0Y2 defective injection is constantly the components and
“advanced” functions”
17660
Start of injection valve
0Y2
Interruption/short circuit Line interruption Engine knocks at check 0Y2 (see
to earth 0Y2 defective idle because start of section “Checking
injection is constantly the components and
“advanced” functions”
Line-to-earth short Not enough power
circuit because start of
0Y2 defective injection is constantly
“retarded”
17663
Coolant temperature
sending unit 0B1

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Possible
Fault code Possible effect Correction
cause
Short circuit to earth Line-to-earth short Black smoke at start Check 0B1 (see
circuit section “Checking
0B1 defective A preheating of about the components and
20 s is always carried functions”)
out
17664
Coolant temperature
sending unit 0B1
Interruption/short circuit Line interruption or Black smoke at start Check B1 (see
to positive line-to-positive short section “Checking
circuit the components and
0B1 defective A preheating of about functions”)
20 s is always carried
out.
17762
Control sleeve position
sensor 0B3
Electrical fault in circuit Line interruption or line Indicator light for Check 0B3, check
short circuit preheating time flashes sensor for control
Injection pump Poor driving sleeve position and
defective characteristics fuel quantity positioner
Engine stop (see section “Checking
the components and
functions”)
17945
Fuel shut-off valve 0Y1
Malfunction 0Y1 leaking or jamming Reduced power check 0Y1 (see
0Y1 defective Engine stop section “Checking
the components and
functions”)
17946
Fuel shut-off valve 0Y1
Interruption/short circuit Line interruption or Reduced power check 0Y1 (see
to earth line-to-earth short section “Checking
circuit the components and
0Y1 defective Engine stop functions”)
17969
Fuel quantity positioner
System deviation Line interruption or line Indicator light for Check 0B3, check
short circuit preheating time flashes sensor for control
Injection pump Poor driving sleeve position and
defective characteristics fuel quantity positioner
Engine stop (see section “Checking
the components and
functions”)
17970
Fuel quantity positioner

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Possible
Fault code Possible effect Correction
cause
Upper limit stop Upper limit stop value Reduced power Check 0B3, check
reached sensor for control
0B3 defective/blocked Bucking sleeve position and
fuel quantity positioner
(see section “Checking
the components and
functions”)
17971
Fuel quantity positioner
Lower limit stop Lower limit stop value Black smoke Check 0B3, check
reached sensor for control
0B3 defective/blocked Rough idling sleeve position and
fuel quantity positioner
(see section “Checking
the components and
functions”)
17978
Engine control unit 0N1
disabled
Line interruption Engine starts running Check line between
or short circuit of for a short time and then engine control unit and
communication line stalls immobilizer control unit
acc. to wiring diagram
Indicator light for
Engine control unit 0N1 preheating time flashes Replace 0N1 (see
not replaced together section “Checking
with control unit of the components and
immobilizer functions”)
Engine control unit 0N1
defective
Immobilizer 0N2
defective
18008
Voltage supply terminal
15
Voltage too low No voltage at “Ignition Engine does not start Checking the voltage
ON” (terminal 15) Poor driving supply of the injection
characteristics up to system
engine stop
18009
Voltage supply relay
terminal 30
Implausible signal No voltage at “Ignition Engine does not start Checking the voltage
ON” (terminal 15) Poor driving supply of the injection
characteristics up to system
engine stop
18020
Engine control unit

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Possible
Fault code Possible effect Correction
cause
Wrong coding Invalid control unit Indicator light for Encode control unit
coding preheating time flashes
18026
Glow plug relay 0K1
Short circuit to positive Short circuit to positive No preheating check 0K1 (see
0K1 defective Poor cold start section “Checking
behaviour the components and
Indicator light for functions”)
preheating time flashes
18027
Glow plug relay 0K1
Interruption/short circuit Line interruption or No preheating Check 0K1 (see
to earth line-to-earth short Poor cold start section “Checking
circuit behaviour the components and
Indicator light for functions”)
preheating time flashes
18033
Drive data bus Encode control unit
18034
Drive data bus Encode control unit
18048
Control unit 0N1 Control unit 0N1 Poor driving Replace 0N1 (see
defective internally defective characteristics section “Checking
Engine stop the components and
functions”)
18056
Drive data bus Encode control unit
19456
Indicator light for
preheating time
Fault message from Faults in data lines to Check connective
display the display resistance for data bus

Standardised data blocks

Safety measures

CAUTION

The use of gauges and test instruments, which

can fall off the truck and be destroyed, may be
required for test drives.
Always fasten testers and gauges well
If necessary, block up the truck

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Data blocks - prerequisites for testing

• The coolant temperature must be at least
80 °C.
• All electrical loads such as rear window hea-
ting must be switched off.
• The air conditioning system of the truck, if fit-
ted, must be switched off.
• Display the fault history.
No fault should be stored in the fault history.

Test procedure
¾ Start the diagnostic program “Pathfinder”.
¾ In the menu “Inputs and outputs” select the
button “Standardised data blocks”.

Display Group Display field 1 Display field 2 Display field 3 Display field 4
Coolant
Engine speed Injection quantity Pump voltage
01 temperature
xxxx/min xx.x mg/stroke x.xx V
xxx.x °C
Desired exhaust Actual exhaust gas
Engine speed On/off ratio of EGR
03 gas recirculation recirculation
xxxx/min valve
xxx mg/stroke xxx mg/stroke
Desired start of Actual start of
On/off ratio of start
Engine speed injection injection
04 of injection valve
xxxx/min xx.x° BTDC xx.x° BTDC
0 - 100 %
(ATDC) (ATDC)
Actual start of
Coolant
Engine speed injection Start quantity
05 temperature
xxxx/min xx.x° BTDC xxx mg/stroke
xxx.x °C
(ATDC)
Coolant Intake pipe
Fuel temperature
07 temperature temperature
xxx.x °C
xxx.x °C xxx.x°C
Atmospheric Intake pipe
Mass air flow
10 pressure pressure
xxx mg/stroke
xxxx mbar xxx mbar
On/off ratio of
Desired charge Actual charge
Engine speed charge pressure
11 pressure pressure
xxxx/min limitation
xxxx mbar xxxx mbar
0 - 100 %
Coolant Controller battery
Preheating time
12 temperature voltage
xx.xx s
xxx °C xx.x V
Deviation of Deviation of Deviation of Deviation of
13 cylinder 1 cylinder 2 cylinder 3 cylinder 4
x.xx mg/stroke x.xx mg/stroke x.xx mg/stroke x.xx mg/stroke

Data block 01 - evaluation

• Engine idling
• Engine warm, coolant temperature not under
80 °C

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1 Engine
Diesel engine

Data block Number Display field Desired value

1 Engine speed 960 - 1050 rpm
2 Injection quantity 7.0 -13.0 mg/stroke
01
3 Pump voltage 1.86 - 2.12 Volt
4 Coolant temperature 80 - 110°C

Evaluation “Injection quantity”

Display Possible cause Correction

Under 7 mg/stroke Mixture too rich Replace the injection pump
Warm up engine at increased
Engine too cool
Over 13 mg/stroke speed and repeat test
Mixture too lean Replace the injection pump

Evaluation “Pump voltage” (sensor voltage for

control sleeve travel)

Display Possible cause Correction

under 1.86 Volt Mixture too rich Replace the injection pump
Warm up engine at increased
Engine too cool
Over 2.12 Volt speed and repeat test
Mixture too lean Replace the injection pump

• Engine with full load 2500 - 2800 rpm

• Coolant temperature not under 80 °C

Data block Number Display field Desired value

1 Engine speed 2400 - 2850 rpm
2 Injection quantity 25 - 39 mg/stroke
01
3 Pump voltage 3.1 - 4.3 Volt
4 Coolant temperature 80 - 110 °C

Data block 04 - evaluation

• Engine idling
• Engine warm, coolant temperature not under
80 °C

Data block Number Display field Desired value

1 Engine speed 960 - 1050 rpm
2 On/off ratio of start of injection valve 2 - 95 %
04
3 Desired start of injection 5° to 10° BTDC
4 Actual start of injection 5° to 10° BTDC

Evaluation “Desired start of injection”

Display Possible cause Correction

Warm up engine at increased
over 5° BTDC Engine too cool
speed and repeat test

Evaluation “Actual start of injection”

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 Engine 1
Diesel engine

Display Possible cause Correction

Warm up engine at increased
Engine too cool
speed and repeat test
Dynamically check and adjust
Over desired value Injection pump stands “too early”
start of injection
Start of injection valve 0Y2
Check 0Y2, actuator diagnosis
defective
Injection pump stands extremely Dynamically check and adjust
“too late” start of injection
Less than desired value Injection timing inhibited Check 0Y2, actuator diagnosis
Start of injection valve 0Y2
Actuator diagnosis
defective

• Engine with full load 2500 - 2800 rpm

• Engine warm, coolant temperature not under
80 °C

Data block Number Display field Desired value

1 Engine speed 2400 - 2800 rpm
2 On/off ratio of start of injection valve 45 - 85 %
04
3 Start of injection (desired) 1.0° to 8.0° BTDC
4 Start of injection (actual) 1.0° to 8.0° BTDC

Evaluation “Actual start of injection”

Display Possible cause Correction

Start of injection valve 0Y2
Check 0Y2, actuator diagnosis
defective
If the deviation to the actual
Injection pump stands extremely Dynamically check and adjust
value is too great (approx. 5°)
incorrectly start of injection
Air in the fuel system Check fuel supply

Evaluation “On/off ratio of start of injection valve”

Display Possible cause Correction

Check 0Y2, actuator diagnosis
Start of injection valve 0Y2 Dynamically check and adjust
Desired value out of tolerance
defective start of injection
Check fuel supply

Data block 05 - evaluation

• Engine idling
• Engine warm, coolant temperature not under
80 °C

Data block Number Display field Desired value

1 Engine speed 960 - 1050 rpm
2 Coolant temperature > 80 °C
05
3 Start of injection (actual) 5° - 10° BTDC
4 Start quantity 12 - 16 mg/stroke

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1 Engine
Diesel engine

Data block 07 - evaluation

• Ignition switched on
• Cooled, stationary engine

Data block Number Display field Desired value

1 Fuel temperature about ambient temperature
2 Coolant temperature about ambient temperature
07
3 Intake pipe temperature about ambient temperature
4 free

A specification of desired temperature values

is not possible. With the engine cooled down,
the temperature values of fuel, intake air and
coolant have to be approximately the same as
the ambient temperature.
Check the relevant sensor if there are significant
deviations.
Evaluation “Fuel temperature”

Display Possible cause Correction

Check 0B3. In case of a fault
Short or fuel temperature
-5.4 °C the data block indicates a fuel
sending unit 0B3 faulty
temperature of -5.4 °C.

Evaluation “Intake pipe temperature”

Display Possible cause Correction

Check 0B4. In case of a fault
Intake pipe temperature sending
approx. 136.8 °C the data block indicates a fuel
unit 0B4 defective
temperature of -136.8 °C.

Evaluation “Coolant temperature”

Display Possible cause Correction

Check 0B1. In the event of a
Large deviation from the ambient Short or coolant temperature
fault, the fuel temperature is
temperature sending unit 0B1 faulty
indicated instead.

Data block 10 - evaluation

• Engine idling
• Engine warm, coolant temperature not under
80 °C

Data block Number Display field Desired value

1 Mass air flow 360 - 600 mg/stroke
2 atmospheric pressure 900 - 1100 mbar
10 Intake pipe pressure (charge
3 1000 - 1200 mbar
pressure)
4 free

• Engine with full load 2500 - 2800 rpm

• Coolant temperature not under 80 °C

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 Engine 1
Diesel engine

Data block Number Display field Desired value

1 Mass air flow 700 - 1050 mg/stroke
2 atmospheric pressure 900 - 1100 mbar
10 Intake pipe pressure (charge
3 1600 - 2100 mbar
pressure)
4 free

Evaluation display “Mass air flow”

Display Possible cause Correction

Speed too high or too low Read desired value at 2800 rpm
Charge pressure too low Check charge pressure control
Check 0B6. In case of a fault,
Less than desired value the data block indicates a
Mass air flow meter defective constant mass air flow of approx.
550 mg/stroke over the entire
speed and load range.

Evaluation display “Intake pipe pressure (charge

pressure)”

Display Possible cause Correction

Charge pressure control
Less than desired value defective
Turbocharger defective Check charge pressure control

Over desired value Turbocharger defective

Data block 11 - evaluation

• Engine idling
• Engine warm, coolant temperature not under
80 °C

Data block Number Display field Desired value

1 Engine speed 960 - 1050 rpm
On/off ratio of valve for charge
2 50 - 75 %
11 pressure control
3 Charge pressure (desired) 1000 - 1200 mbar
4 Charge pressure (actual) 1000 - 1200 mbar

• Engine with full load 2500 - 2800 rpm

• Coolant temperature not under 80°C

Data block Number Display field Desired value

1 Engine speed 2400 - 2850 rpm
On/off ratio of valve for charge
2 10 - 20 %
11 pressure control
3 Charge pressure (desired) 1600 - 2100 mbar
4 Charge pressure (actual) 1600 - 2100 mbar

Evaluation display “Charge pressure (actual)”

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1 Engine
Diesel engine

Display Possible cause Correction

Charge pressure control
Less than desired value defective Check 0Y2, actuator diagnosis
Turbocharger defective
No fault. If possible, repeat
Measurement carried out at measurements at an atmosphe-
great height ric pressure ranging from 900 -
1100 mbar
Over desired value Turbocharger defective Check charge pressure control

Data block 12 - evaluation

• Ignition switched on
• Engine warm, coolant temperature not under
80°C

Data block Number Display field Desired value

1 Preheating time in seconds 0
2 Coolant temperature 80 - 110 °C
12
3 Battery voltage 13.5 - 14.5 Volt
4 free

Data block 13 - evaluation

• Engine idling
• Engine warm, coolant temperature not under
80°C

Data block Number Display field Desired value

1 Deviation of cylinder 1
2 Deviation of cylinder 2
13 -2.0 to +2.0 mg/stroke
3 Deviation of cylinder 3
4 Deviation of cylinder 4

Evaluation “Idle adjustment”

Display Possible cause Correction

The cylinder is supplied with
-xx mg/stroke Drop in cylinder performance
more fuel
The cylinder is supplied with less
+xx mg/stroke Rise in cylinder performance
fuel

The injection system has an idle speed control

which compensates any differences in perfor-
mance between the individual cylinders (com-
ponent tolerances, nozzle throughput, compres-
sion, etc) by a selective metering of the injected
fuel at idle speed.
Differences are detected at idle speed with the
signal from the engine speed sensor, which sup-
plies four signals per crankshaft revolution to
the control unit. If all signals are received at the
same rhythm, all cylinders perform the same
work. If one cylinder has a poorer performance,

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 Engine 1
Diesel engine

the crankshaft needs more time for the next half

crankshaft revolution. On the other hand, a po-
werful cylinder accelerates the crankshaft so
much that it needs less time.
Once the control unit has detected a difference,
the relevant cylinder is supplied with a larger
or smaller amount of fuel until the engine runs
“smoothly” again.

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1 Engine
Diesel engine

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 Transmission 2
Description of transmission

Technical data of travel drive

Variable-displacement pump
Manufacturer Linde
Type HPV 105 -02
Number of pistons 7
Piston diameter
max working pressure 425+20 bar
Boost and pilot oil pressure 21 bar
Swash angle 0 - 19.7°
Pump speed 2800 rpm
Oil flow downstream of flow regulator valve
Type of pump control hydraulic
Control of hydraulic pump control with Linde Truck Control (LTC)
Frictional connection to the engine flexible coupling

Drive axle
Manufacturer Linde
Type AH 50 -03
Fixed-displacement hydraulic motor HMF 135 -02, two items
Number of pistons 11
Piston diameter
Swash angle 20.8° constant
Planetary hub reduction gearbox, ratio 6.67:1

Brake
on extended motor shaft
Oil pressure multiple disc brake fully encapsulated
acting only as a parking and emergency brake

Triple gear pump

Pump V1 for working hydraulics and steering q1 = 9 cm3/rev
Pump V2 for working hydraulics and steering q2 = 18 cm3/rev
Pump V3 for feed, servo control and hydraulic fan
q3 = 16 cm3/rev
drive

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2 Transmission
Description of transmission

Linde Truck Control (LTC)

Digital electrohydraulic control unit • Truck brakes with emergency function and IC
engine shuts down.
The trucks of series 39X come equipped with the
• Error code appears on the display.
latest control technology. Instead of a hydraulic
accelerator, which was used in the previous truck These measures can be reversed by shutting
series, a compact electronic control unit featuring down the truck with the ignition switch. When
a highly efficient microcontroller performs all restarting, the control unit checks whether there is
control functions of the travel drive and the still a fault. If there is no fault, the truck continues
working hydraulics. to drive as in normal operation. If there is still a
fault, the error code re-appears on the display
Adaptation for various trucks and one of the above-mentioned measures will
be taken.
The electronic control unit is capable of control-
ling trucks of various series and different engines. Brake
To take into account deviating truck parameters,
every truck cable harness is coded for the definite The brake is designed as a parking and emer-
identification of the truck. gency brake. It is operated mechanically and
hydraulically by a valve. A microswitch is actua-
Fault detection ted at half and full brake pedal travel.

The processor of the electronic control unit

Release valve
evaluates analogue and digital signals. It detects
non-logical states and system faults and outputs The release valve is a safety valve which, in the
a fault message on the test instrument via the event of a failure of the activation of the pump
serial interface. The control unit also initiates control, automatically decelerates the truck or
various measures, depending on the hazard prevents the truck from moving off at all. The
potential of the fault: valve is closed when the accelerator is depressed
• Warning light flashes. and opens when the truck is standing still.
• RPM limitation of IC engine.
• Truck brakes with normal deceleration and
does not move off again.

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 Transmission 2
Description of transmission

System overview

1 Engine 10 Reduction gearbox

2 Variable-displacement hydraulic pump HPV 105 11 Multiple disc brake
-02 12 Fixed-displacement hydraulic motor HMF 135
3 Gear pump V1, q1 = 9 cm3/rev -02
4 Restrictor valve 1Y10 P1 Working hydraulics port
5 Gear pump V2, q2 = 18 cm3/rev P3 Steering port
6 Cold start valve 1Y11 P4 Hydraulic fan motor and feed port
7 Gear pump V3, q3 = 16 cm3/rev LS Load sensing port
8 Priority valve S Suction port of gear pump
9 Retarder valve 1Y1 (H 45/50 only) T Tank port

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2 Transmission
Travel drive

Travel drive - introduction

Control of truck speed power control prevents the maximum available
engine power from being exceeded.
The truck speed of a hydrostatically powered
truck results from the speed of the IC engine
Power control - travel drive
and the hydraulic ratio (output of the variable-
displacement pump to input of the hydraulic The swash angle of the variable-displacement
motors). The output volume of the variable- pump and the speed of the IC engine are auto-
displacement pump depends on the pump speed, matically controlled by the electronic control unit
swash angle and the specific output volume of the in accordance with the pedal travel.
pump.
A speed sensor reports the engine rpm to the
To maintain a speed specified by the accelerator, control unit. A variance comparison is carried out
the electronic control regulates the speed of the in the control unit and the variable-displacement
IC engine and the swash angle of the pump. pump is destroked in case of a deviation.
In the case of a speed specified by the accelerator If the engine power is exceeded (engine overload
(desired speed), each change in the engine too high), the electronic control unit reduces the
speed is compensated by a change in the swash pump swash angle (reduced power demand)
angle of the pump. This is only possible as far until the engine speed (actual value) again
as power limit of the IC engine, beyond this the corresponds to the value specified with the
speed is reduced. The various control situations accelerator. Through this variance comparison
at different accelerator positions will be discussed of the engine speed, the power demand of the
below. working hydraulics is also included in the control
unit.
Moving off on a slope
Speed control - working hydraulics
The parking brake is operated mechanically and
hydraulically with the brake pedal via a valve. In When the tilting and auxiliary hydraulic system
addition, two microswitches (1 and 2) are also functions are operated, the central control lever
actuated with the brake pedal. for working hydraulics (joystick) supplies a signal
When the brake pedal is released half way, via a potentiometer to the electronic control unit
microswitch 1 is actuated, while the brake is which increases the speed of the IC engine.
still applied. If the accelerator is depressed at When the lifting function is performed, a signal is
the same time, the electronic control unit only given to the electronic control unit which increa-
allows a limited pump swash angle as the truck is ses the speed of the IC engine to the maximum
accelerating against an applied brake. value.
When the brake pedal is released fully, mic-
roswitch 1 actuates (microswitch 2 remains in Truck speed governing
its initial position) and the limitation of the pump The swash angle of the variable pump and
swash angle is removed, the brake is released the speed of the IC engine are automatically
and the truck moves off without rolling back. controlled by a variance comparison with the
accelerator via the electronic control. If a higher
Driving speed of the IC engine is requested through a
When the accelerator is depressed, the variable- signal supplied to the control unit by the working
displacement pump strokes up proportionally to hydraulics, the control unit responds to the
the pedal stroke and the speed of the traction higher value and allows the engine speed to
motor increases. The truck speed reaches the increase. As the actual speed is now higher than
desired speed specified by the accelerator. the desired speed specified by the accelerator,
the electronic control unit immediately reduces
Depressing the accelerator further and thus spe- the angle of the pump swash plate to prevent an
cifying a faster truck speed increases, proportio- increase in the driving speed.
nally to the pedal travel, the engine speed and the
pump swash angle. When the maximum engine The governing occurs so fast that the driver does
speed is reached, the truck speed and the pump not notice a change in speed.
swash angle are at their maximum values. The

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 Transmission 2
Travel drive

Braking Reversal of the direction of travel

The minimum and maximum swivelling time of When reversing the direction of travel, the signals
the variable-displacement pump from Qmin to for the new direction and the engine speed are
Qmax or from Qmax to Qmin is specified by the only released when the electronic control unit
electronic control unit. It controls the swivelling has sensed the neutral (zero) position of the
speed of the variable-displacement pump within variable-displacement pump. This ensures that
this range depending on the engine speed. the engine speed drops to low idle speed and
This achieves a braking deceleration, which is increases only when the new direction has been
(almost) unaffected by the load condition of the selected.
truck.

Hydraulic pump control with electronic control

1 Locknut 8 Way valve

2 Swash angle adjustment screw 9 Proportional valve
3 Setting bush - start of delivery 10 Solenoid
4 Locknut 11 Release valve
5 Control springs 12 Nozzle
6 Servopiston 13 Way valve
7 Control pilot x Max travel of servopiston 15.1 mm

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2 Transmission
Travel drive

1 Release valve 7 Adjustment of start of delivery - forward direction

2 Proportional valve, forward 8 Setscrew for swash angle, forward direction
3 Start of delivery adjustment, reverse direction 9 Test port for pilot oil pressure F’’ upstream of the
4 Swash angle adjustment screw, reverse direc- release valve
tion 10 Hydraulic zero position
5 Test adapter Y - pilot oil pressure, forward 11 Proportional valve - reverse direction
direction
6 Test adapter Z - pilot oil pressure, reverse direc-
tion

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 Transmission 2
Travel drive

1 Purge valve 5 Pressure relief valves

2 Changeover valve 6 Brake valves (pilot valve)
3 Boost pressure valve 7 Bypass valve
4 Brake valves (main control valve)

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2 Transmission
Travel drive

1 Retarder valve 1Y1 (H 45/50 only)

2 Restrictor valve 1Y10 for working hydraulics
compensation
3 Cold start valve 1Y11 for cold start system at
temperatures under 5 °C

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 Transmission 2
Travel drive

1 Hydraulic variable-displacement pump HPV 105 14 Boost pressure valve p = 21.0+0.5 bar
-02 15 Bypass valve
2 Release valve 16 Combined feed/pressure relief valve p =
3 Proportional solenoid 425+20 bar
4 Proportional valve 17 4/3-port directional control valve
5 2/2-port directional control valve 18 Purge valve p = 15 5 bar, output Q = 19 litres/min
6 Nozzle Ø 1 mm 19 Brake valves (pilot valve) for H 40: p = 110 bar,
7 Cradle control piston for H 45/50: p =250 bar
8 Control circuit nozzles 20 Brake valves (main control valve)
9 Pressure relief valve 1 bar A1/A2High-pressure port, forward direction
10 4/2-port directional control valve B1/B2High-pressure port, reverse direction
11 Pilot valve T Oil reservoir port
12 Change filter F Feed port
13 Servopiston U Protective valve/oil reservoir port

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2 Transmission
Travel drive

1 Pump V1 for working hydraulics and steering, q1 6 Priority valve

= 9 cm3/rev 7 Retarder valve 1Y1 (H 45/50 only)
2 Restrictor valve 1Y10 P1 Working hydraulics port
3 Pump V2 for working hydraulics and steering, q2 P3 Steering port
= 18 cm3/rev P4 Hydr. fan motor and feed port
4 Cold start valve 1Y11 LS Load sensing port
5 Pump V3 for feed, servo control and hydraulic S Suction portpumps
fan drive; q3 = 16 cm3/rev T Return line port

Functional description - pump control Depressing an accelerator controls the related

solenoid (3) with a signal dependent on the
When the engine is running and the brake pedal pedal stroke. A pressure corresponding to the
depressed, the solenoid of the release valve (2) signal value of the solenoid is applied through
is de-energised. Supply pressure is applied from the downstream proportional valve (4) to the
port F to nozzle (6); the passage downstream servopiston (13). The servopiston (13) moves
of the nozzle is connected with the reservoir and pushes the oil flowing off at the opposite end
via the open release valve (2) and is therefore through the related proportional valve (4) into
pressureless. The control piston (7) is connected the reservoir. The movement of the servopiston
to port F on both sides via the pilot valve ((11), (13) adjusts the pilot valve (11) through which the
the directional control valve (10) and the control control piston (7) is supplied with pressure, and
circuit nozzles (8), thus holding the variable pump the pump starts to stroke.
(1) in the hydraulic zero position.
Releasing the accelerator towards zero stroke
After receiving a switching signal from the elec- reduces the signal at the solenoid. As a result, the
tronic control, the release valve (2) closes the proportional valve reduces the pressure going to
connection to the hydraulic oil reservoir so that the servopiston, the pump reduces the swash
boost pressure also builds up behind the nozzle angle and the truck is braked.
(6). The two directional control valves (5) are set
to the open position so that boost pressure from If the electronic control unit detects a fault in
passage F is applied to the unactuated proporti- the speed control, the truck is brought to a stop,
onal valves (4). Simultaneously, the directional independent of the position of the accelerator.
control valve (10) is shifted from the throttled to To do this, the release valve (2) is de-energised
the unthrottled position. so that the pressure behind the nozzle (6) drops

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 Transmission 2
Travel drive

to 0 bar. The directional control valves (5) move directional control valve (10). This arrangement
to the closed position, thus removing the boost prevents sudden braking and initiates controlled
pressure going to the proportional valves (4). braking deceleration.
This action also shifts the proportional valve (4),
which is controlled by the solenoid (3), mechani- Emergency stop with the brake pedal
cally to the home position. The pressure applied
to the servopiston (13) is removed. The piston is If, due to a failure, the truck cannot be braked with
pushed mechanically to the zero position, which the accelerators, an emergency stop with the
also shifts the pilot valve (11) to the zero posi- brake pedal is possible.
tion. The opening of the release valve (2) and The two microswitches in the pedal box are
the concomitant pressure drop to 0 bar at F" also actuated together with the brake pedal, thus
switches the directional control valve (10) from de-energizing the release valve (2) and the truck
the unthrottled to the throttled position. decelerates as with a fault in the controller. At
The reset time of control piston (7) is delayed via the same time the lift pressure of the multiple
the control circuit nozzles (8) and the throttling via disc brakes drops and the truck is also be braked
mechanically.

Start of delivery of the pump

Adjustment of start of delivery and swash angle for Setting the hydraulic zero position
reverse direction 7 Pilot housing
1 Setscrew (swash angle) 8 Slotted nut
2 Set ring (start of delivery) F Servo pressure upstream of release valve (test
3 Slotted nut (start of delivery) point)
Y Pilot pressure, forward direction
Adjustment of start of delivery and swash angle,
Y2 Solenoid, forward
forward direction
Y3 Solenoid, reverse direction
4 Slotted nut (start of delivery)
Y4 Release valve
5 Set ring (start of delivery)
Z Pilot oil pressure, reverse direction
6 Setscrew (swash angle)

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2 Transmission
Travel drive

Start of delivery of the variable-displace-

ment pump - check
Prerequisite: Jack up the truck and block 1 wheel.
¾ Start the engine and release the brake pedal.
¾ Connect the laptop and select “Inputs + Out-
puts/Travel/Currents”
¾ Depress the forward or reverse accelerator
until iY2 or iY3 = 440 - 460 mA.
¾ Hold the accelerator in this position and iY2
= 440 - 460 mA loosen the slotted nut (4) and
turn the adjustment ring (5) until the wheel just
begins to turn.
¾ Then lock the slotted nut (4) again.
¾ If iY3 = 440 - 460 mA, perform the same adjus-
tment at adjustment ring (2).
¾ Release the locked wheel.
¾ Fully depress the accelerator. A value of
1220 mA must be displayed via the tab “Cur-
rents” of the diagnostic software (preset by the
control).
¾ Measure the maximum wheel speed.
The maximum wheel speed is the mean of the
speed of both drive wheels.
Desired speed: n = 160-20 rpm
Start of delivery - diagram

NOTE

If the electric values are correct but the full wheel

speed is not reached, then check and adjust the
stroke of the servopiston (swash angle of pump. Q Volume flow
s Accelerator stroke
I Release valve shifts
Swash angle - adjustment II Drive wheels start to turn
¾ Jack up the truck and lock 1 wheel. II Max speed of drive wheels

¾ Start the engine and release the brake pedal.

¾ Loosen the locknut on the setscrew (1) on the
Y side of the hydraulic control and turn in the
setscrew (1) until the free wheel just starts to
turn.
¾ Then turn the setscrew (1) out for 12 turns and
relock the locknut.
¾ Repeat the same procedure on side Z.

Hydraulic zero position - adjustment

¾ Jack up the truck and lock wheel.

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 Transmission 2
Travel drive

¾ Start the engine and release the brake.

¾ Centre the pilot housing (7). To do this, loosen
the grooved nut (8) and turn the pilot housing
(7) to one side until the free wheel just begins
to turn.
¾ Repeat the procedure in the opposite direction.
¾ Measure and halve the distance between both
positions and turn the pilot housing (7) towards
the centre exactly by this value.
¾ Lock the pilot housing (7) with the slotted nut
(8).
¾ Release the locked wheel.
Repeat the adjustment if one drive wheel is still
turning.

Bypass valve
Towing
In order to tow the truck, two requirements must
be met:
• the bypass valve must be in the towing position
• the multiple disc brake must be released

WARNING
The truck can not be braked when the multiple
disc brake is released.
For towing, an additional vehicle of sufficient pul-
ling power and braking force is required for the
unbraked trailing load.
The fork truck may only be towed with a solid
connection (tow bar)

Opening the hydraulic bypass valve

¾ Open the bonnet.

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2 Transmission
Travel drive

¾ Use a socket to loosen the collar nut (1) on the

housing on the left of the variable-displace-
ment pump.
¾ Turn the setscrew (2) out 2 turns with a socket.
¾ Lock the setscrew with collar nut (1), retighten
to 60 Nm.
¾ Close the bonnet.

Releasing the multiple disc brake

NOTE

The brake release valve is located below the floor

plate on the left of the truck frame.

¾ Remove the floor mat.

¾ Stick an Allen wrench through the floor plate
and loosen the cheese head screw (3) by ap-
prox. 6 turns.
¾ Sit down on the driver’s seat.
¾ Depress (pump) the brake pedal about 20 ti-
mes in the easy range up to noticeable resis-
tance until the brake is released.

Discharge device
To ensure a certain degree of cooling, it is ne-
cessary to exchange the oil in the closed circuit.
By means of a switch-over valve, a certain vo-
lumetric flow is always discharged from the low
pressure side.

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 Transmission 2
Travel drive

Switch-over valve - function

If both high-pressure lines are depressurised or

under charging pressure (zero position of pump),
the two switch-over pistons A1 and B1 are in the
spring-centred central position. No hydraulic oil
can flow to the discharging valve, neither from
high-pressure port A nor from B.
However, if high pressure builds up, e.g., on the
A-side, this piston A1pushes into the direction of
port B and takes the piston B1 with it.
The poppet at piston A1 is used as a limit stop,
preventing high pressure from escaping from
spring chamber A1 to the discharging valve.
From port B, oil may now flow to the restrictor
(2) mm.

Discharging valve - function

Via the restrictor (2) mm, a volumetric flow passes
from the low pressure side of the closed circuit to
the oil reservoir.
The discharging valve (1) p = 15 bar with the
serially connected restrictor (2) maintains the
charging pressure at p = 21 bar.

Service Training – 394 804 2401 EN – 01/2005 2-15

2 Transmission
Travel drive

Switch-over valve - remove and install

Discharge device - sectional drawing

1 Pressure reducing valve p = 15 bar,

Md = 30+5 Nm
2 Restrictor
3 Switch-over valve

Required special tools

• Key for switch-over valve 000 941 9438

2-16 Service Training – 394 804 2401 EN – 01/2005

 Transmission 2
Travel drive

Hydraulic fan drive

1 Gear pump V2, q2 = 16 cm3/rev 7 Boost pressure valve p = 21+0.5 bar

2 Bypass valve S Suction line
3 Proportional solenoid Y5 P4 Pressure port
4 Hydraulic motor q = 12 cm3/rev F Boost pressure port
5 Impeller T6 Return to reservoir
6 Cooler

Fan drive - method of operation bypass valve (2) is open and the fan motor (4)
is stationary. The fan only starts running up to
The hydraulic fan drive is a hydraulic motor (4) approx. 1000 rpm if these temperatures are ex-
with a displacement of q = 12 cm3 and supplied ceeded. Then the speed rises proportionally to
by boost pressure pump V2 (1). The hydraulic the temperature.
motor (4)is fitted with an impeller (5) which draws
the cooling air from the engine compartment and This cooling concept achieves the optimum
delivers it to the outside. The fan speed depends operating temperature within a shorter time,
on the speed of the engine and the coolant and reduces noise development and eliminates peak
hydraulic oil temperatures. temperatures better.

Temperature transmitters sense the tempera-

tures of the coolant and hydraulic oil and send WARNING
them to the LTC control unit. The LTC controls
When maintenance work is carried out with the
proportional valve Y5 (3), which in turn controls bonnet open, the still stationary fan motor can
a bypass valve (2) mounted on the fan motor (4). suddenly start running at a relatively high speed
The speed of the fan motor (4) is influenced by due to the temperature control.
the controlled oil flow. If the coolant temperature Do not put your hands in the fan.
is lower than approx. 95 °C and the hydraulic
Keep your distance.
oil temperature is lower than approx. 68 °C, the

Service Training – 394 804 2401 EN – 01/2005 2-17

2 Transmission
Hydraulic truck diagnosis

Overview and explanations of

diagnosis
Pressure test points - overview

1 Pressure test point HP forward 9 Sealing point brake pressure right/left

2 Pressure test point HP forward 10 Sealing point HP
3 Pressure test point Y (forward) a HPV 105 -02
4 Pressure test point Z (reverse) b Fan motor
5 Pressure test point F" (supply pressure) c Low-pressure filter
6 Pressure test point (supply pressure) d Control valve of working hydraulics
7 Pressure test point MP (working hydraulics) e Brake valve
8 Pressure test point BR (brake pressure) f Drive axle AH 50-03

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 Transmission 2
Hydraulic truck diagnosis

Required special tools

• Screw coupling M14 x 1.5, ET No.
000 951 6400
• Screw coupling M10 x 1, ET No. 000 951 6407
• Screw coupling M8 x 1, ET No. 000 951 6402
• Screw coupling with sealing plug, ET No.
000 903 1126
• Pressure gauge 0 - 40 bar, ET No.
000 943 0106
• Pressure gauge 0 - 600 bar, ET No.
000 943 0107
• Banjo screw, ET No. 000 903 1126
• Banjo screw, ET No. 000 903 1130
• Screw coupling M12 x 1.5, ET No.
000 951 6410
• Sealing plug, ET No. 000 951 3900
• Digital tachometer, for example, from
Horn GmbH
P. O. Box 1162
D-7036 Schönaich
The screw couplings, adapters, measuring wires
and pressure gauges required for the measure-
ments are in the measuring box 000 941 6000.

Pressure values - overview

Position of accelerator
Position of brake pedal Test point Pressure (bar)
pedal
0-position released F 21,0
0-position released F" 0
actuated by approx. 4 mm released F" 21,0
Forward pedal fully actuated released Y 21,0
Reverse pedal fully actuated released Z 21,0
0-position released BR 21,0
0-position actuated BR 0

Troubleshooting - explanations
The functional tests and possible trouble-shoo-
ting procedures are performed separately for the
individual main groups and refer to the following
components or functions:
• Hydraulic brake system
• Power-assisted steering
• Beginning of swing-out of the HPV 105 -02
• Hydrostatic travel drive

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2 Transmission
Hydraulic truck diagnosis

Prior to performing the work described below,

the oil level must be checked and corrected if
necessary.
If a test procedure requires the installation of a
pressure gauge or a screw cap, the ventilation
valve of the hydraulic oil tank must be screwed
out. This reduces the pretension in the oil reser-
voir.
The installation positions of the pressure gau-
ges/screw caps are shown in the hydraulic dia-
gram.
Unless specifically mentioned, all pressure
measurements are to be performed with the
brake pedal released.
For some test procedures, the decoupling of the
drive axle AH 50-03 is required. To do so, pro-
ceed as follows:
• Screw off the union nut of the HP hoses from
the screw necks of drive axle AH 50-03.
• Seal threaded plug with sealing plug (4 pieces
000 951 3900).
• Reconnect hoses.

Abbreviations used
LP gauge Low-pressure gauge
HP gauge High-pressure gauge
LP Low pressure
HP High pressure
Forward pedal Accelerator pedal forward
Reverse pedal Accelerator pedal reverse
p Pressure differential

Hydrostatic travel drive - check

Prerequisites for testing - fault finding
• The truck is blocked up so that both drive
wheels can turn freely.
• The hydraulic power steering is functioning.
• The parking brake is applied.
• The electronic LTC control does not indicate a
fault (warning light not flashing).
• The engine can be started.
• The pedal adjustment is OK.
• The electric truck diagnosis with a laptop
shows no fault
• The test readings and settings are OK.

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 Transmission 2
Hydraulic truck diagnosis

Remove the M8 x 1 screw coupling with high-

pressure gauge from test point (1) and connect
it to high-pressure test point (2) (low pressure
gauge stays on port F’’) and then perform the
check with the reverse accelerator.
The readings now refer to the other direction of
travel and components.

Fault finding - travel drive

Step Yes No
Procedure
Type (Test) (Test)
Connect screw coupling
000 951 6410 and the low
1
pressure gauge to port F
Action
of the filter (C), engine at
idling speed, brake applied
2
LP approx. 21.0 bar? Go to steps 9 - 12 Go to step 3
Test
Seal port E at the brake
3 release valve (e) with a
Action blind plug and repeat the
test.
Problem in the brake
4
LP approx. 21.0 bar? system. Please refer to Go to step 5
Test
“Hydraulic brake system ”
Check or replace boost
5
pressure valve, repeat the
Action
test.
6
LP approx. 21.0 bar? Go to steps 9 - 12 Go to step 7
Test
Disconnect axle AH 25 -03
7
with plug 000 951 3900,
Action
repeat the test.
8 AH 50 -03 defective, repair HPV 105 -02 defective,
LP approx. 21.0 bar?
Test or replace. repair or replace.
Connect the laptop to the
test connector. Connect
9
screw coupling 000 951
Action
6407 and the low pressure
gauge to port F" (5).
10 Start the engine, start
Action “Pathfinder”.
Select “Inputs/Out-
11 puts/Traction/Output Si-
Action gnals” and release the
brake.
Depress the forward
12 accelerator and reverse
Action accelerator until iY4 is
operated.

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2 Transmission
Hydraulic truck diagnosis

Step Yes No
Procedure
Type (Test) (Test)
Check the operation of the
When iY4 is operated, the solenoid and hydraulic
13
pressure at test point 5 Go to steps 14 - 16 section of the release
Test
rises to approx. 21.0 bar. valve or replace the valve
assembly.
Install screw coupling 000
14
951 6400 with LP pressure
Action
gauge to port Y.
Start the engine, re-
lease the brake. Select
“Inputs/Outputs/Trac-
tion/Flows F/Pump for-
15 ward (iY2)”and depress
Action the forward accelerator
gently while reading the
increase in current at iY2
(solenoid, forward direc-
tion).
Observe the increase in
16
pressure at port Y and start
Action
of rotation of the wheels.
Current at iY2 rises,
Check or replace
pressure stays at 0 bar,
proportional valve iY2.
wheels not turning.
17
Current and pressure Check the servo control or
Test
rising, wheels not turning. cradle control piston.
Current and pressure
Go to step 18.
rising, wheels turning.
depress the forward
18 accelerator again and read
Action rise in current at iY2 at start
of wheel rotation.
19 Wheels start rotating at I =
Go to step 22. Go to step 20.
Test 440 - 460 mA.
Adjust start of delivery,
20
see “Start of delivery of the
Action
pump”.
21 Start of delivery can be Check hydraulic servo
Go to step 22.
Test adjusted. control.
Depress the Forward
22
accelerator as far as the
Action
stop.
Perform electrical
23 Current at iY2 approx.
Go to step 24. diagnosis with
Test 1220 mA.
“Pathfinder”.
Fully depress the Forward
24
accelerator again and read
Action
the pressure.
Check or replace
25 Pressure at stop at least
Go to step 26 proportional valve and
Test 16 bar or more.
servo control.

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 Transmission 2
Hydraulic truck diagnosis

Step Yes No
Procedure
Type (Test) (Test)
With forward accelerator
fully depressed, determine
26
avg. wheel speed.
Action
Desired speed: n =
160-20rpm
Check swash angle of
variable displacement
27
Average wheel speed OK. Go to steps 28 - 31 pump, see “Swash
Test
angle of the variable
displacement pump ”.
Connect M10 x 1 screw
28
coupling and low pressure
Action
gauge to port F’’ (5).
Connect screw coupling
29 000 951 6402 with high
Action pressure gauge to HP test
point (1).
Block the brake (press
30
brake piston fully in with a
Action
long screwdriver).
Depress the Forward
31
accelerator, determine
Action
high and low pressure.
High pressure approx.
Pressure relief valve for
32 425 bar
forward travel direction is
Test Low pressure approx.
OK.
21.0 bar
High pressure far under Internal leakage.
425 bar Possible causes: feed
Low pressure approx. valves/relief valves or
21.0 bar bypass valve leaking.
Leakage in the high
pressure section for
As the high pressure rises,
forward travel.
the low pressure drops to
Disconnect AH 50 -03 to
0 bar.
localise the fault in HPV
105 -02 or AH 50-03.

Service Training – 394 804 2401 EN – 01/2005 2-23

2 Transmission
Hydraulic truck diagnosis

Hydraulic motor HMF 135 -02

1 Reduction gearbox GRGH -02 2 Hydraulic motor HMF 135 -02

1 Driveshaft 4 Oil drain plug

2 Tapered roller bearing 5 Valve plate
3 Swash plate with hydraulic motor assy. 6 O-ring

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 Transmission 2
Hydraulic truck diagnosis

7 Tapered roller bearing 11 Circlip

8 Brake housing 12 Brake piston
9 Discs 13 O-ring
10 O-ring 14 Brake disc

1 Wheel shaft 6 Grooved nut Md =2200+100 Nm, with Loctite 270

2 Tapered roller bearing 7 Planet carrier
3 Shaft seal 8 Magnetic plug
4 Distance ring 9 Transmission case
5 Tapered roller bearing sun gear

Service Training – 394 804 2401 EN – 01/2005 2-25

2 Transmission
Hydraulic truck diagnosis

HPV 105 -02 pressures - tests

Required special tools
• Screw coupling M10 x 1, Part No.
000 951 6407
• Screw coupling M12 x 1.5, Part No.
000 951 6410
• Screw coupling M14 x 1.5, Part No.
000 951 6400
• Pressure gauge 0 - 40 bar, Part No.
000 943 0106

Boost pressure at the filter

Test point: item 6
¾ Screw off the plug at the filter (c).
¾ Connect the M12 x 1.5 screw coupling, Part
No. 000 951 6410.
¾ Connect the low pressure gauge 0 - 40 bar,
Part No. 000 943 0106.
¾ Start the engine.
Desired value = 21.0 bar

Boost pressure to HPV 105 -02

Test point: item 5
¾ Screw off the plug at the servo cover F’’.
¾ Connect the M10 x 1 screw coupling, Part No.
000 951 6407.
¾ Connect the low pressure gauge 0 - 40 200 bar,
Part No. 000 943 0106.
¾ Start the engine.

Accelerator
0 bar
unactuated
Accelerator actuated 21.0 bar

Test start of delivery of HPV 105 -02

Test points 3 and 4
¾ Remove plug Y (3) and Z on the servo cover.
¾ Install the M14 x 1.5 screw coupling, Part No.
000 951 6400.
¾ Connect the low pressure gauge 0 - 40 bar,
Part No. 000 943 0106.
¾ Start the engine.
¾ Actuate the forward and reverse accelerator
until the wheels start rotating.

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 Transmission 2
Hydraulic truck diagnosis

Desired value for p (differential pressure) at Y

and Z when the wheels start rotating:
reversing & reverse: p = 4 bar

High pressure test of HPV 105 -02

Test points 1 and 2
¾ Screw off the plug on the HPV 105 -02.
¾ Install the M8 x 1 screw coupling, Part No.
000 951 6402.
¾ Connect the high pressure gauge.
¾ Release the brake pedal.
¾ Push in the brake piston of the valve (e) with a
long screwdriver.
¾ Operate the forward and reverse accelerator.
Desired value: pHP = 425+20 bar

Determination of average wheel speed

¾ Start the engine.
¾ Release the brake pedal.
¾ Depress the forward accelerator against the
stop.
¾ Measure the left and right wheel speed.
¾ Depress the reverse accelerator against the
stop.
¾ Measure the left and right wheel speed.

NOTE
During the wheel speed test keep the particular
accelerator against the stop.

Desired wheel speed:

forward 160 rpm

reverse 160 rpm

Example: Calculation of average wheel speed

left side 180 rpm

right side 140 rpm
Total 320
divided by 2
Result 160 rpm

Service Training – 394 804 2401 EN – 01/2005 2-27

2 Transmission
Hydraulic truck diagnosis

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 Chassis 3
Chassis

Axle suspension
¾ Glue the inside of the bearing half to the axle
bearing with Loctite 2K-Pur glue (grease-free).
¾ Apply the glue evenly in the form of a snake
line.
The repair kit consists of:

Double cartridge of glue 50 ml 7 379 200 411

Two injection nozzles (mixing
7 319 209 900
tube)
Adapter for cartridge 7 319 209 940

Torque for M20 screws (1): Md = 540 Nm

Service Training – 394 804 2401 EN – 01/2005 3-1

3 Chassis
Chassis

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 Undercarriage 4
Steering system

Steering system - functional description

2 Gear pump V3 for infeed q3= 16 cm3/rev LS Load-sensing port

3 Priority valve P Pressure port, steering control valve
4 Steering control valve with primary valve, se- P2 Pressure port, working hydraulics
condary valves and make-up valves P3 Pressure port, steering outlet
6 Steering cylinder R Pressure port, steering cylinder, right
L Pressure port, steering cylinder, left

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4 Undercarriage
Steering system

1 Pump V1 for working hydraulics and steering, q1 11 Make-up valves

= 9 cm3/rev 12 Secondary valves DBV2, p = 220+10 bar
2 Restrictor valve 1Y10 P
3 Pump V2 for working hydraulics and steering, q2 P1 Working hydraulics port
= 18 cm3/rev P3 Steering port
4 Cold start valve 1Y11 P4 Hydr. fan motor and feed port
5 Pump V3 for infeed, servo control and hydraulic LS Load sensing port
fan drive; q3 = 16 cm3/rev S Suction port of gear pump
6 Priority valve T Return line port
7 Retarder valve 1Y1 (H 45/50 only) T1 Return line port
8 Primary valve DBV1, p = 120 +5 bar L Steering cylinder port, left
9 Check valve R Steering cylinder port, right
10 Steering control valve

Steering system - method of operation is cut off by the steering control valve (13). As a
result, the pressure in the LS line rises. This pres-
The oil delivered by pump V2 (3) enters the sure rise controls the priority valve (6) in such
centred priority valve (6). a way that the delivered oil flow of pump V2 is
When the steering control valve (13) is not activa- completely available for the steering system. De-
ted, an oil flow of Q ~ 1 L/min flows via P3 and P pending on the movement of the steering control
through the steering control valve (13) and leaves valve (13), the steering cylinder (11) is supplied
it at (T.). The main part of the oil flow of pump V2 with an oil flow via the ports (R) or (L). The oil
(3) is available at port P2 of the working hydraulic which is pushed out of the steering cylinder (11)
system. The pressure port for load-sensing (LS) during the steering movement returns to the re-
is connected to the reservoir (T) via the steering servoir via the steering control valve (13) and port
control valve. (T).

The steering system is protected by the primary In case self-aligning forces lead to pressure
valve (9) with pmax = 120+5 bar. peaks in the steering circuit (eg by driving over
an obstacles), the pressure peaks are limited to
Steering pmax = 220+10 bar by the secondary valves (10).

When the steering system is actuated, the reser-

voir connection of the load-sensing pressure port

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 Undercarriage 4
Steering system

Steering against the stop Emergency steering with the engine

stationary
When steering the steering cylinder (11) against
the stop, the pressure at port (P) of the steering Emergency steering means that a rotor pump
control valve, on the pressure side of the steering in the steering control valve (13) is actuated by
cylinder and in the load sensing line (LS) rises the steering wheel. Depending on the sense
to the setting of the primary valve (9) (pmax = of rotation, this rotor pump draws oil from one
120+5 bar. The primary valve opens and reduces chamber of the steering cylinder and pumps it
the load sensing pressure to the reservoir. As into the other chamber. In case of an oil loss due
a consequence, the priority valve moves to a to a leakage in the circuit, oil is replenished from
position in which only the oil flow necessary for the reservoir line (T) via the make-up valves (12).
maintaining the maximum pressure is delivered
to the steering cylinder. The remaining larger
portion of the oil flow delivered by V2 is diverted
via the working hydraulics pressure port (P2) to
the reservoir.

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4 Undercarriage
Brake system

Brake release valve

Connection diagram

A Piston H Auxiliary operation valve

B Pump chamber I Brake pedal
C Auxiliary pump check valve BR Brake port
D 2/2-port directional control valve K Pressure relief valve brake p = 20 bar
E Pilot oil pressure port T Oil reservoir port
F Check valve (make-up)

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 Undercarriage 4
Brake system

Brake release valve - cross section: Brake operation in the towing mode

A Piston H Auxiliary operation valve

B Pump chamber I Brake pedal
C Auxiliary pump check valve J Ball Ø 14 mm
D Control edge BR Brake port
E Pilot oil pressure port K Brake relief valve, p = 20 bar
F Check valve (suction port) L Valve cone (not shown on connection drawing)
G Ball Ø 9 mm T Oil reservoir port

Brake release valve - Functional descrip-

tion
Brake released (pressure in brake chamber BR)
• Piston is in not-actuated position (piston travel
s = 0 mm).

Service Training – 394 804 2401 EN – 01/2005 4-5

4 Undercarriage
Brake system

• Oil flows from port E (passage 2) via passages

15, 16, 7, 21 to the brake port (passage 3).
• As a result, brake chamber BR is pressurised,
the brake is released and does not brake
Brake operates (no pressure in brake chamber
BR)
• Piston is in actuated position (piston travel s =
11 mm).
• Oil flows from port BR (passage 3) via passa-
ges 21, 7, 16 and 15 to the oil reservoir port
(passage 1).
• As a result, brake chamber BR is not pres-
surised and the brake returns to its operating
position and brakes
Towing mode (build-up of pressure in brake
chamber BR)
• The auxiliary operation valve screw is screwed
out and closes the connection between pas-
sage 21 (brake port) and passage 7 (control
edge of brake plunger) with the 14 mm ball.
• Simultaneously the 9 mm ball closes the con-
nection of the pump chamber (passage 18) to
the oil reservoir (passage 6).
• The auxiliary pump check valve (C) and the
valve cone block the connection to the pump
chamber.
• A movement of the piston forces oil from pump
chamber (B) through the auxiliary pump check
valve (C) into the brake chamber or draws the
oil from the oil reservoir line into the check
valve.
• Pressure builds up in brake chamber (BR).
• The pressure in brake chamber (BR) is limited
by the pressure relief valve to p = 20 bar.

Brake release valve - bleed (eg after a

replacement)
¾ With the truck running, turn out the screw plug
(1) at the side.
¾ Actuate the brake lever several times until oil
free of air bubbles emerges (collect the oil).
¾ Screw in the plug while the brake lever is actu-
ated (to avoid air entering the system).

Brake cables - adjustment

Two cables with different adjustments act on the
plungers of the brake release valve.

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 Undercarriage 4
Brake system

• The parking brake cable is set to a travel of

16 mm. After the travel of 16 mm a noticeable
resistance can be felt.
• The service brake cable is set to a travel of
19 mm
Brake cables - location
Parking brake cable: left
Service brake cable: right
Before attaching the brake cables to the yoke of
the brake release valve, the nuts must be turned
either fully forward (1) of fully backwards (2).

Parking brake cable - adjustment

¾ Push the handbrake lever (3) to the position
“Release brake”.

Service Training – 394 804 2401 EN – 01/2005 4-7

4 Undercarriage
Brake system

¾ Hook the cable assembly (4) loosely to the

holder of the brake release valve.
¾ Tighten the front nut until the lever (6) contacts
the unactuated piston rod (5) without play.

¾ Lock with the nut (1)

Service brake cable - adjustment

¾ Hook the cable assembly loosely to the holder
of the brake release valve.

¾ Tighten front nut (1) until the nipple of the cable

assembly has a play of approx. 2 mm (s) to the
yoke (6) in the neutral position.

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 Undercarriage 4
Brake system

¾ Operate the brake pedal.

About 5 mm before the pedal touches the stop
screw (8), you should feel a clearly noticeable
resistance.
When the pedal touches the limit stop, the yoke
must have a clearance of approx. 0.5 mm to the
valve plunger. Correct the adjustment, if neces-
sary.
¾ Lock with the nut (2).

Brake cables - functional test

DANGER
In case of an incorrect adjustment of the brake
cables, the truck can possibly no longer be
braked with the brake.
In order to avoid serious accidents, the functional
check of the brake must be carried out with the
truck blocked up.

After completion of the adjustment, carry out a

functional check for:
• easy movement of the brake cables.
• operation of the brake upon actuation of the
parking brake.
• operation of the brake upon actuation of the
service brake.

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4 Undercarriage
Brake system

Brake valves

1 Pressure relief valve p = 15 bar 8 Brake valve, reverse direction

2 Restrictor 8a Brake valve, forward direction
3 Changeover valve 9 Pilot valve for reverse direction, p = 110 bar for H
4 HPV 105 -02 40, p = 250 bar for H 45/50
5 Charging pump V2q2 = 16 cm3/rev 9a Pilot valve for forward direction, p = 110 bar for H
6 Boost pressure valve p = 21.0 bar 40, p = 250 bar for H 45/50
7 Pressure relief valve, forward direction p = 10 Bypass valve
425+20 bar 11 HMF 135
7a Pressure relief valve, reverse direction p =
425+20 bar

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 Undercarriage 4
Brake system

1 4 Nozzles, diameter 0.5 mm

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4 Undercarriage
Brake system

Brake valve - functional description

7 Pressure relief valve, forward direction p = 9 Pilot valve for reverse direction, p = 110 bar for H
425+20 bar 40, p = 250 bar for H 45/50
7a Pressure relief valve, reverse direction p = 9a Pilot valve for forward direction, p = 110 bar for H
425+20 bar 40, p = 250 bar for H 45/50
8 Brake valve, reverse direction 10 Bypass valve
8a Brake valve, forward direction

To achieve the maximum deceleration in both Furthermore, the combined boost pressure/relief
directions of travel without overspeeding (reving valves have been modified to ensure a pressure
up) the engine, a brake valve for each direction limiting to 425+20 bar.
of travel has been installed in the closed circuit.
Each of these brake valves is controlled via an Forward travel
auxiliary control valve if the supporting pressure
pHD1 rises above 110 bar for the H 40 or above When driving, the oil flow passes through the
250 bar for H 45/50. brake valves, which are without function then.
The pilot valves are switched to the neutral
position at a high pressure below 110 bar or

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 Undercarriage 4
Brake system

250 bar. The boost pressure is available at the As a result, the supporting pressure pHD1 at the
pilot valve and the brake valves have not yet been variable displacement pump HPV 105 -02 cannot
activated. rise over 110 bar or 250 bar, so that the speed of
the engine is limited.
The high pressure for traction pHD2 is limited to
a maximum of 425+20 bar by the pressure relief
valve. This function is identical for forward and Switching function
reverse travel. If the high pressure pHD1 rises above 110 bar
or 250 bar during braking, the pilot valve is
Braking (deceleration) - in forward direc- activated, the available boost pressure goes
tion to the brake valve, which is modulated and limits
the supporting pressure in the closed circuit at
Due to the dynamics of the mass of the truck and the variable displacement pump HPV 105 - 02
the power reversal resulting therefrom during to a maximum of 110 bar or 250 bar. The high
braking (pulling into pushing force), the hydraulic pressure pHD2 at the hydraulic motors can rise to
motors drive the variable displacement pump. a maximum of 425 bar.
The pressure is reversed: LP becomes HP and
HP becomes LP. Since the pump is supported This function is identical for forward and reverse
on the engine, the speed of the engine is reved travel.
up. To counteract the uncontrolled speed rise
and thus a reduction of the deceleration and
an increase of the noise level, a brake valve is
activated at pHD1 > 110 bar or 250 bar.

Brake system - check

Prerequisites for testing - functional test
• Truck blocked up so that both drive wheels can
turn freely.
• Pedal adjustment OK.
• Brake pedal in released “position”.
¾ Start the engine and push in the brake piston
of the brake valve with a long screwdriver.
¾ Depress the forward and reverse accelerators.
If pHP > 420 bar and the wheels do not turn during
this check, the brake system is okay
If the wheels turn during this check, the brake
system must be checked

Prerequisites for testing - fault finding

¾ Trucks raised so that both drive wheels can
rotate freely.
¾ Bonnet open.
¾ Floor plate raise.
¾ Pedal adjustment OK.
¾ Engine and travel drive at operating tempera-
ture.
¾ Brake pedal in the “brake locked” position and
applied.

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4 Undercarriage
Brake system

Fault finding - brake system

Step Yes No
Proceed
Type (Test) (Test)
Connect M12 x 1.5 screw
1 coupling and LP pressure
Action gauge to port 7 of the LP
filter (C).
2 Start the engine and read
Action the pressure on the gauge
3
Pressure at least 21.0 bar? Go to step 6 - 8 Go to step 4
Test
Seal line port E at the
4 brake release valve (E)
Action with blanking plug 000 903
1129 and repeat the test
5 Brake release valve Check the hydrostatic
Pressure at least 21.0 bar?
Test defective travel drive
Connect a pressure gauge
with banjo bolt 000 903
6 1130 and a M14 x 1.5
Action screw coupling to port
BR on the brake release
valve(E)
Release the brake and
7
check the pressure with
Action
the engine running
8
Pressure at least 21.0 bar? Go to step 9 Go to step 11 - 12
Test
With the engine running,
9 fully depress brake pedal
Action and watch the pressure
gauge
Brake release valve does
10 Does pressure drop to
Go to step 11 - 12 not operate. Repair or
Test approx. 0 bar?
replace valve
Seal port BR at the brake
11
release valve with blanking
Action
plug 000 903 1129.
12 Start the engine and
Action release the brake.
Depress the forward or
13
reverse accelerator as far
Action
as the stop.
The multiple disc brake
14 at the turning wheel is
Do the drive wheels turn? Braking system okay.
Test defective. Remove and
correct the fault.

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 Undercarriage 4
Brake system

Step Yes No
Proceed
Type (Test) (Test)
Remove the test adapter
at BR and connect an
LP pressure gauge with
15 adapter 000 951 2115
Action and screw coupling 000
951 6400 to port BR on
the brake release valve
(without brake line).
Check the pressure with
16
the engine running and
Action
brake released.
Brake release valve
17
Pressure at least 21.0 bar? Go to step 18 - 20 defective, repair or replace
Test
valve.
Remove the test adapter
18 and install the LP pressure
Action gauge again to port BR
(with brake line).
Seal port BR at the
19
right-hand brake with
Action
banjo bolt 000 903 1126
Check the pressure with
20
the engine running and
Action
brake released.
21 Seal on right-hand brake Seal on left-hand brake
Pressure at least 21.0 bar?
Test piston defective piston defective

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4 Undercarriage
Brake system

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 Electrical system/electronic system 6
Central electrical system

Arrangement of the interface connectors console - truck

1 5X1/5X4, connector 12 pins (lighting/working 10

lights) 11 5X9, connector 6 pins (reversing warning light)
2 7X1, connector 9 pins (soot filter connector) 12 9X9, connector 2 pins (heating)
3 9X5, connector 6 pins (washing system pumps) 13 6X5, connector 3 pins (truck data management)
4 4X2, connector 6 pins (reversing signal) 14 9X7, connector 3 pins (seat heating)
5 5X3, connector 3 pins (reversing warning light) 15 9X8, connector 3 pins (radio)
6 9X15, connector 9 pins (12 V socket) or: 5X14, 16 X15, connector 2 pins (CAN interface)
connector 3 pins (working lights items 5 and 6 17
7 X10, connector 18 pins (interface standard 18 X11, connector 9 pins (interface standard equip-
equipment - optional equipment) ment - optional equipment)
8 6X1, connector 10 pins (composite instrument) 19 ON2/OX2, connector, 5 pins (immobilizer)
9 9X1, connector 9 pins (windscreen wiper)

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6 Electrical system/electronic system
Central electrical system

Layout of relays and fuses for standard and optional equipment

Fuses
Location Designation Description Rating
6.1 5F2 Working lights items 3, 4 15 A
7.5 A
6.2 5F3 Working lights items (5+) 4
15 A for 2 working lights
7.5 A
6.3 5F4 Working lights items (7+) 8
15 A for 2 working lights
6.4
Composite instrument (terminal
9.1 F5 2A
30)
Composite instrument (terminal
9.2 F6 2A
15)
9.3 F7 Horn 15 A
9.4 F8 Traction/lift control (terminal 15) 2A
15 A diesel
14.1 9F10 12V socket
20 A LP gas
14.2 9F9 Heater/air conditioning 20 A
14.3 9F6 Seat heating 20 A
Hazard warning light/rotating
14.4 4F3 7.5 A
beacon
17.1 F9 Traction/lift control (terminal 30) 15 A
17.2 F10 Power supply for ignition coil 20 A LPG controlled
15 A diesel
17.3 F11 Engine control unit (terminal 30)
5 A LP gas
2 A diesel
17.4 F12 Engine control unit (terminal 15)
10 A LP gas
18.1 5F8 Headlight left 7.5 A
18.2 5F9 Headlight right 7.5 A
18.3 5F10 Position light left 5A
18.4 5F11 Position light right 5A
19.1 5F5/5F1 Lighting/working lights items 1, 2 15 A
19.2 5F6/5F13 Hazard warning flasher 10 A
19.3 5F7 Brake light 5A
19.4 5F12 Interior lighting 5A
20.1 9F1 Windscreen wiper 2A

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 Electrical system/electronic system 6
Central electrical system

Fuses
Location Designation Description Rating
20.2 9F2 Windscreen wiper, front 10 A
20.3 9F3 Windscreen wiper, rear and roof 7.5 A
20.4 9F4 Washing system pumps 10 A
21.1 9F7 Radio terminal 30 5A
21.2 9F8 Radio terminal 58 10 A
21.3 4F1 Reversing 10 A
21.4
23.1 7F1 Soot filter 5A
23.2 7F2 Soot filter 20 A
23.3 7F3 Soot filter 30 A
23.4
24.1 F13 Terminal 30
24.2 F14 Terminal 58 2A
24.3 F15 Terminal 15 10 A
2.4.4 F16 Coolant after-running pump 5A

Fuse LMH Part No.

2A 7 919 086 800
5A 7 919 086 803
7.5 A 7 919 086 804
10 A 7 919 086 805
15 A 7 919 086 806
20 A 7 919 086 807
30 A 7 919 086 809

Relay
Location Designation Description
1 9K1 Windscreen wiper relay, front
2 9K2 Windscreen wiper relay, rear
3 9K3 Windscreen wiper relay, roof
4 4K1 Reversing signal relay
5 K1 Relay terminal 58 (70 A)
7 0K2 Relay VW control unit diesel
0K1 Glowing relay (70 A) or
8
OK4 relay for coolant after-running pump (LP gas only)
10 5K2 Relay brake lights
11 5K1 Flasher
12 5K3 Hazard warning flasher relay for reversing
13 5K4 Working lights items 8
15 K3 Truck shutdown relay
16 K2 Starter relay (70 A)
22 7B1 Soot filter buzzer

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6 Electrical system/electronic system
Central electrical system

Composite instrument

1 Composite instrument 16 Clock

2 Hydraulic oil temperature warning light 17 Service reminder symbol
3 Battery charge warning light 18 Function button
4 Engine oil pressure warning light 19 Reset button
5 Electric controller (LTC) malfunction light 20 Symbol “parking brake on”
6 Coolant temperature warning light 21 Symbol “Do not start engine”
7 Overload warning light* 22 Symbol “Operating hours until next service” (only
8 Soot filter warning* readable on indicator (14) for 4 seconds )
9 Coolant level warning light* 23 Mast position sensing symbol
10 Hydraulic oil filter warning light* 24 Text field
11 Fuel level indicator 25 Preheating indicator/fault light (VW engine)
12 Information display 26 Air filter restricted warning light
13 Soot filter symbol* 27 Not used
14 Hour meter 28 Not used
15 Sand glass symbol

* = Optional

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 Electrical system/electronic system 6
Central electrical system

Location of composite instrument

The composite instrument (1) is located at the
overhead guard at the top right corner. It serves
as a warning indicator and as an information dis-
play (12).

Display

DANGER

In case of overload, the load/overload indica-

tor “7”lights up red. The forklift can tip over
due to overloading, which can result in severe
injuries.
Put the load down immediately.
Observe the load capacity diagram.

Possible malfunctions
Indicator Purpose
Correction
Not enough oil in hydraulic circuit
Illuminates if the specified Oil not as specified
temperature limit is reached. Oil filter clogged
Hydraulic oil temperature
If the admissible temperature Accumulation of debris on oil
warning light (2) (colour: red)
limit is reached, a buzzer also cooler
sounds. Switch off buzzer with reset
button (19)
Ribbed V-belt torn or tension too
low, tensioner defective.
Battery charge warning light (3) Illuminates in case of malfunc- Cables defective
(colour: red) tions in the electrical system. Alternator defective
Charging regulator or regulator
switch defective
Not enough oil in crankcase
Engine overheated
Illuminates if the oil pressure of Oil not as specified
Engine oil pressure warning light
the engine lubrication is too low. Internal leak in lubricating oil
(4) (colour: red)
A buzzer also sounds. circuit
Switch off buzzer with reset
button (19).
Please contact your authorised
Linde dealer.
Fan motor defective
Illuminates if the specified Thermal switch defective
temperature limit is reached. Radiator blocked
Coolant temperature warning
If the admissible temperature Leak in cooling circuit
light (6) (colour: red)
limit is reached, a buzzer also Coolant level too low
sounds.
Switch off buzzer with reset
button (19).

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6 Electrical system/electronic system
Central electrical system

Possible malfunctions
Indicator Purpose
Correction
Symbol is illuminated orange
with a normal load.
DANGER
Overload warning light (7)1
Symbol is illuminated red in case The load must be put down
of overload. immediately. Check the load
capacity diagram.
Soot filter warning (8)2 (colour: Illuminates if the soot filter must
Regenerate soot filter.
red) be regenerated.
Coolant level warning light (9)3 Illuminates if the coolant level
Coolant level too low, refill
(colour: orange) drops below the minimum level.
Hydraulic oil filter warning light Illuminates if the micro-filter
Micro-filter restricted, replace
(10)4 (colour: orange) requires servicing
Fuel level indicator (11) (colour:
green or red, depending on fuel It indicates the current fuel level.
level)
Illuminates or flashes and shows
Symbol “soot filter” (13)5 the remaining capacity by means Soot filter restricted, regenerate
of 4 symbols in the text field (24).
If a defective composite
instrument has to be replaced,
the elapsed operating hours
Indicates the operating hours of
must be recorded. Record the
the truck. This readout serves
information on durable tape
as proof of the elapsed hours of
Hour meter (14) and affix it near the composite
the truck and of the inspection
instrument. It is also possible
and maintenance services to be
to set the new instrument to
carried out.
the actually elapsed time later.
Please contact your authorised
Linde dealer for this service.
Flashes when the hour meter
is running (only if ignition is on
Symbol “sand glass ”(15)
and the engine speed exceeds
500 rpm)
The time is displayed in the The display is changed to
24-hour format. To set the 12-hour format with diagnostic
Clock (16)
correct time, use the buttons unit. Please contact your
(18) and (19). authorised Linde dealer.
If the number of operating hours A reset or change of the
until the service interval is 0 or intervals is only possible with
Service reminder symbol (17) less, the symbol first flashes the appropriate diagnostic unit.
for 10 s after each start before Please contact your authorised
lighting permanently. Linde dealer for this service.
Function button (18) Function depending on model

1 Option
2 Option
3 Option
4 Option
5 Option

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 Electrical system/electronic system 6
Central electrical system

Possible malfunctions
Indicator Purpose
Correction
To set the time, switch off the
warning buzzer and for other
Reset button (19)
functions, depending on the
model.
Illuminates when the parking
Symbol “parking brake” (20)
brake is operated.
Illuminates if the engine has
been stalled. In this case,
Start again after a short waiting
Symbol “Do not start engine” (21) restarting the engine is only
period.
possible after a short waiting
period.
After switching the ignition on,
the operating hours until the
next servicing are indicated in
the Display field ((14), counting
Symbol “Operating hours until backwards). The symbol (22)
next service” (22) is lighted. After 4 seconds
the display (14) switches
automatically to the operating
hours of the truck and the sand
glass symbol (15) flashes.
Symbol “Mast position sensing” Illuminates if the admissible tilt
(23)6 angle is exceeded.
Text field (24) Used for display purposes
Preheating indicator/fault light Authorised Linde dealers.
Illuminates in the preheating time
(VW engine) (25) (colour: Flashing could mean a problem
and is then extinguished.
orange) with the VW engine.
Air filter restricted warning light Illuminates in case of excessive Air filter restricted, clean or
(26) (colour: orange) restriction of the air filter. replace.
Not used (27) and (28)

6 Option

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6 Electrical system/electronic system
Central electrical system

Positions of the working lights

Working lights item 1

Working lights item 2

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 Electrical system/electronic system 6
Central electrical system

Working lights item 3

Working lights item 4

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6 Electrical system/electronic system
Central electrical system

Working lights item 8

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 Hydraulics 7
Working hydraulics

Functional description of control valve

1 Pressure reducing valve for lifting and tilting 7 Solenoid valve, auxiliary hydraulic system 2
2 Emergency lowering 8 Test point “P”
3 Pressure reducing valve, auxiliary hydraulic 9 Release valve
system 10 Solenoid valve for lifting
4 Solenoid valve for lowering 11 Solenoid valve for forward tilting
5 Solenoid valve for backward tilting
6 Solenoid valve, auxiliary hydraulic system 1

Introduction In the control valve housing, way valves, a ba-

lance valve for recirculating oil, pressure redu-
The valve explained in the following paragraphs cing valves, a safety valve and various check
is an LS control valve with electrohydraulic valves are located.
activation in monoblock design. The control
valve is available either as triple monoblock
Release valve, balance valve for recircu-
(single auxiliary hydraulic section) or quadruple
lating oil, pressure reducing valve
monoblock (double auxiliary hydraulic sections).
The safety valve is a spool valve which influences
Section 1 Lifting/Lowering
both the LS signal path and the control pressure
Section 2 Forward and backward tilting supply. When the joystick is not actuated, port
Section 3 Auxiliary hydraulic system 1 2Y9 on the safety valve is de-energised. This
Section 4 Auxiliary hydraulic system 2 pushes the safety valve into the following position
by means of spring power:
• The LS signal path is connected to the oil
reservoir.

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7 Hydraulics
Working hydraulics

• The control pressure supply X is shut off from Thus the pressure reducing valve creates a
the supply of the pressure reducing valves. control pressure, depending on the control signal.
• The pressure reducing valve supply is placed This control pressure displaces the way valve
on the oil reservoir over the solenoid actuating piston (4) against a feedback spring.
rod. The restrictor located in the way valve is enlarged
Only the oil reservoir pressure is reported to with rising piston stroke. In parallel with the
the balance valve for circulating oil in the spring displacement of the piston, the load pressure
chamber by a flow restrictor in the LS path. With is reported to the LS path and the balance valve
running engine, the balance valve for circulating for circulating oil adjusts the pump pressure to a
oil is now set to the position which causes the certain pressure level so that a constant control
available pump delivery to flow to the oil reservoir p is always available at the restrictor. As a result
at a D p of approx. 8 bar (corresponding to the of this switching logic, the volumetric flow to the
spring power at the balance valve). If a joystick load is a function of the variation of the surface
is actuated, the solenoid at the safety valve is area of the restrictor.
activated and the valve carries out the following As regards the non-return valve (6) during lifting,
functions: the oil just passes through it. The excess volume-
• The LS path is closed. Thus, the maximum tric flow is fed to the oil reservoir via the balance
available load pressure acts together with the valve for circulating oil.
spring power in the closing direction of the When the lowering function is actuated, control
balance valve for circulating oil. The pump signal 2Y1 is transmitted to the pressure reducing
pressure rises up to the level at which an valve. The resulting reduced control pressure
equilibrium of forces is restored at the balance acts on the way valve piston (4) and at the same
valve for circulating oil. time on the unlocking valve (7).
• The control pressure supply X is shut off
The unlocking valve has an operating point which
from the supply of the pressure reducing
is below the start of the lowering function. In
valves. Only then is it possible to activate the
activated position, the spring chamber of the
respective way valve axis by means of control
non-return valve (6) is connected with the main
signals 2Y1 to 2Y8.
volumetric flow path upstream from the lowering
If the signalled load pressure exceeds the max. restrictor. The advantage of this switching logic
admissible pressure value of the pressure redu- is that the non-return valve opens only at the
cing valve (1), the latter opens a connection to moment at which the lowering restrictor is opened
the oil reservoir. A pressure difference is then re- to the oil reservoir. This allows a very sensitive
duced at the flow restrictor in the LS-path. Now, lowering process even at high loads.
only the pressure set at the pressure reducing
The “lowering stop” function is initiated at each
valve (2) and the spring power act on the balance
interruption of signal 2Y1 or 2Y9. As soon as the
valve for circulating oil. This limits the maximum
unlocking valve (7) lacks control pressure supply,
pump pressure. If the available load pressure is
the above-mentioned connection is closed again
higher, no positive control p may arise at the
and the load pressure in A1 is reflected in the
restrictor of the way valve axis and, thus, there
spring chamber of the non-return valve. As a
is no flow to the load. The excessive volumetric
consequence the valve is tightly closed.
flow of the pump is conducted to the oil reservoir
at the balance valve for circulating oil. An outlet flow controller (5) is integrated in the
way valve piston (4). This regulates a p at the
Functional description - lifting, lowering lowering restrictor, which is adjusted in such a
and emergency lowering way that the lowering speed never exceeds a
maximum of 0.6 m/s even with load. To enable
When the joystick for lifting is actuated, control the lowering of a lifted mast also in case of a
signal 2Y2 is increased in proportion to the failure of the control valve, a connection between
lever excursion. At the same time, the joystick the load A1 and the oil reservoir may be opened
movement switches the above-mentioned safety manually via the emergency lowering function.
valve. The control signal acts on the proportional The emergency lowering screw may be opened
magnet of the pressure reducing valve and limits through a hole in the bottom plate by means of a
the maximum available supply pressure X. socket spanner (opening SW 10).

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 Hydraulics 7
Working hydraulics

After actuation of this function, the emergency the bypass check valve in the brake valve (10)
lowering screw must be tightened again to the to load A2. The load pressure in A2 is signalled
right tightening torque as shown in the installation to the brake valve (11) and pushes it into the
drawing before the truck is started again. opening direction.
The oil pushed out of the cylinders (17) can flow
Functional description - tilting and ba- from port B2 to the oil reservoir via the brake valve
lance valves (11) and the way valve piston (9).
When the joystick is actuated, either control sig- If the mast, due to a drawing load, reaches a
nal 2Y3 (forward tilting) or 2Y4 (backward tilting) speed which is higher than the speed which is
is transmitted to the corresponding pressure re- determined by the volumetric flow in A2, the
ducing valve (forward tilting or backward tilting). pressure in A2 drops and the brake valve (11)
As in case of the lifting function, this causes a is pushed back into closing position by a spring.
displacement of the way valve piston (9). The As a result, the volumetric outlet flow in B2 is
following switching positions are set one after the accumulated which, together with the cylinder
other. surface, constitutes a force that acts opposite to
• Signalling of load pressure to LS path. the direction of traction of the load.
• Opening of outlet to the oil reservoir. The pressure in A2 rises again and is thus able to
• Opening of restrictor between pump and load. open the brake valve (11). Since the brake valve
is a regulating valve, a condition arises in which
As long as the forward tilting/backward tilting the brake valve regulates the mast speed in such
load pressure is the highest pressure in the LS a way that it corresponds exactly to the preset
path, this pressure will be signalled to the balance volumetric flow in A2.
valve for circulating oil and the pump is set to a
value which is higher by the control p. As a The leakage-proof design of the brake valve
result, a volumetric flow which is proportional to prevents any mast movement when the control
the excursion of the restrictor flows to the load. valve is not actuated.
In this situation, the balance valves (12) and (13)
integrated in the piston are fully opened. As soon Functional description - auxiliary hydrau-
as another load signals a higher load pressure, lics
this will be applied to the balance valve located
The principle of operation of the hydraulic attach-
on the inlet side, and the balance valve is pushed
ments (1) and (2) are identical for the A side and B
into closing position. The balance valve then
side. Their maximum volumetric flow depends on
regulates a position in which the control p is
the corresponding maximum control signal 2Y5
still available at the restrictor and the load p
to 2Y8. This value may range from 3 to 48 l/min.
(differential pressure between the highest load
pressure and the tilting pressure) is limited at the The maximum admissible attachment pressure
control restrictor of the balance valve. of the auxiliary function is restricted to a value
between 160 and 180 bar by means of the pres-
Thus the volumetric flow for the tilting function
sure limiting valve (14). The function is explained
remains unaffected even in case of parallel
with the example in attachment A3.
operation with other loads.
When the joystick is actuated, control signal
Functional description - brake valves 2Y6 and simultaneously 2Y9 are released. The
safety valve is activated by control signal 2Y9
Downstream from the way valve (9) in the way even before the auxiliary function starts. Control
valve block are two brake valves (10) and (11). signal 2Y5 acts on the pressure reducing valve
These valves are designed as seat valves (clo- and generates a control pressure which, in turn,
sing without leakage) and each is equipped with acts on the valve piston (15). With rising control
a bypass check valve. The principle of operation signal, the control pressure rises and the valve
of the valves is explained with the example of the piston is moved against a feedback spring in
forward tilting function. opening direction. The load pressure in A3 is
By means of the control signal 2Y3 and the signalled to the balance valve for circulating oil
pressure reducing valve, the way valve piston (3) via the LS path by the displacement of the
(9) is subjected to an excursion in such a way that piston (15). The restrictor at the valve piston links
a volumetric flow is conducted from the pump via the pump path to hydraulic attachment port A3.

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7 Hydraulics
Working hydraulics

Load B3 is connected to the oil reservoir. Due to • H 40, standard, duplex and triplex mast:
the control p generated at the balance valve for p = 250+5 bar
circulating oil, a volumetric flow proportional to • H 45/50, standard, duplex and triplex mast
the restrictor excursion is created. The excess p = 275+5bar
volumetric flow of the pump is fed to the oil
reservoir via the balance valve for circulating ¾ Loosen locknut.
oil.
WARNING
If the load pressure of the hydraulic attachment
exceeds the maximum admissible value for the The pressure increase occurring when the ad-
pressure limiting valve (14), the control p at justing screw is screwed in happens very quickly
a flow restrictor in the LS path will be reduced. and can reach inadmissible levels. The setting is
Thus, there is no pressure difference between very sensitive.
the pump pressure and load pressure A3, and no Very carefully set the adjusting screw in maxi-
volumetric flow may flow to the load. mum increments of 60° rotation angle.
The attachments are not provided with any
¾ Screw in adjusting screw (pressure increase).
device to maintain the volumetric flow to the load
during parallel operation with other functions at a ¾ Unscrew adjusting screw (pressure reduction).
constant level.

Pressure reducing valve setting instruc-

tions
Pressure adjustments:

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 Hydraulics 7
Working hydraulics

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7 Hydraulics
Working hydraulics

Circuit diagram of working hydraulics

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 Hydraulics 7
Working hydraulics

1 Release valve (safety valve) Ports

2 Pressure reducing valve for lifting, forward tilting A1 Lift cylinder
and backward tilting A2 Forward tilting
3 Balance valve for recirculating oil B2 Backward tilting
4 Way valve for lifting/lowering A3/B3Auxiliary hydraulic system 1
5 Flow control valve A4/B4Auxiliary hydraulic system 2
6 Non-return valve TP Test point for recirculating and maximum pres-
7 Unlocking valve for the non-return valve sure
8 Emergency lowering, lowering P Pump V1
9 Way valve for forward tilting and backward tilting X Pilot pressure
10 Brake valve for backward tilting T Return flow / oil reservoir
11 Brake valve for forward tilting
Valves
12 Balance valve for forward tilting
2Y1 Valve - lowering
13 Balance valve for backward tilting
2Y2 Valve - lifting
14 Pressure limiting valve for the auxiliary hydrau-
2Y3 Valve - forward tilting
lics
2Y4 Valve - backward tilting
15 Way valve for auxiliary hydraulics 1
2Y5 Valve auxiliary hydraulics B3
16 Way valve for auxiliary hydraulics 2
2Y6 Valve auxiliary hydraulics A3
17 Tilt cylinder
2Y7 Valve auxiliary hydraulics B4
17a Distributor
2Y8 Valve auxiliary hydraulics A4
18 Lift cylinder
2Y9 Release valve (safety valve)
19 Line breakage protection
20 Distributor

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7 Hydraulics
Working hydraulics

Hose layout pump - control valve

B Working hydraulic valve

D Gear pump
E Filter working hydraulics
P Pressure port - control valve
P2 Working hydraulics port

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 Hydraulics 7
Working hydraulics

Hose layout control pressure supply

B Working hydraulic valve P Pressure port - working hydraulics

D Gear pump P(St) Pressure port - control pressure
E Pressure port - control pressure P2 Pressure port - working hydraulics
F Supply pressure P3 Pressure port - steering
M Fan drive P4 Pressure port - fan motor
O LP filter charging pressure LS Pressure port, load-sensing

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7 Hydraulics
Working hydraulics

Hose layout for lifting

1 Lift cylinder A Lift cylinder/mast

2 Line breakage protection (LBS) 2Y1 Valve - lowering
3 Distributor 2Y2 Valve - lifting

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 Hydraulics 7
Working hydraulics

Hose layout for tilting

15 Tilt cylinder B2 Forward tilting

15a Distributor 2Y3 Valve - forward tilting
A2 Backward tilting 2Y4 Valve - backward tilting

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7 Hydraulics
Working hydraulics

Hose layout return flow to oil reservoir

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 Hydraulics 7
Working hydraulics

Hose layout in auxiliary hydraulics for standard mast

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7 Hydraulics
Working hydraulics

Hose layout in auxiliary hydraulics for duplex and triplex mast

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 Loading system 8
Mast

Mast - identification
For the purpose of mast identification, a 12-digit
mast number (serial number) and a type descrip-
tion are attached to the mast channel.
Example of trucks series 394 and mast type 189
in standard, duplex and triplex versions
Serial number: ME 45T 01-46-5/394

E Mast
D Mast channel capacity E = 4 to 5 t
45 Load capacity eg 4.5 t
T S Standard, D Duplex, T Triplex
01 Mast variant 01
46 Height of lift eg 4600 mm
5 Load centre eg 500 mm
394 Series 394

Mast - removal and installation

¾ Remove the fork arms. ¾ Unscrew the four M16 hex head bolts and the
two M20 screws at the lower mast bearing.
¾ Lower the fork carriage.
¾ Separate the toggle joint (M8) of tilt angle
¾ Tilt the mast back approx 2°.
sensor from the mast.
¾ Lift the mast out.
NOTE
The installation of the mast is carried out in the
Tilting the mast back by approx. 2° relieves the reverse order.
rubber bushes of the tilt cylinder mounts.
Tightening torques
¾ Disconnect the pressure lines and, if fitted, the
auxiliary hydraulics lines between the vehicle Mast at drive axle:
and the mast.
M20: Md = 385 Nm
¾ Attach a rope to the top cross member of the
M16: Md = 275 Nm
outer mast, hook it on the hoist and tauten the
rope. Do not exceed the load capacity of the Mounting of tilt cylinder:
hoist and rope.
M20: Md = 275 Nm
¾ Unscrew the hex head bolt at the upper eye
Locking screw for the tilt cylinder:
bolt on both tilt cylinders.
M12: Md = 80 Nm
¾ Remove the inner and outer clamping piece.

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8 Loading system
Mast

A dusting the lift chain (all series)

The lift chain lengthens with operation and must ¾ After locking the nuts, extend the mast as far
therefore be readjusted. as the stop and check the clearance to the
safety stops.
¾ Tilt the mast fully back and lower it completely.
¾ Adjust the chain at the adjusting nut of the
NOTE
chain anchor.
¾ The lower guide pulley of the fork carriage may If the fork carriage touches the safety stops
project by no more than a third of its diameter although the lower rollers project from the profile,
from the inner mast channel. a piston head might have become loose, thus
increasing the stroke inadmissibly.
¾ If two chains are used, make sure that the
lengths of the two chains are identical.

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 Loading system 8
Mast

Adjustment of roller clearance

The described settings refer to the installation whether the existing play has a disturbing effect
of new parts. They do not represent maximum or is scarcely noted. The operating safety of the
allowed wear limits or clearances on masts in mast is not reduced hereby. Only if the wear
use. of the roller diameter is approx. 3% does the
functionality of the mast have to be checked
Wear on mast channels does not occur evenly
critically (on long triplex masts maybe slightly
over the entire length, it can be found rather in the
earlier, on short standard masts possibly only at
main work area instead, for example there, where
4 %).
the support rollers are usually located during
transport.The mast channels are often so unused The operating safety of the mast lasts much
in the upper part that they are almost still like longer as the individual mast components stay
new. As a result larger rollers or additional shims nested into each other even with the greatest
cannot be fitted to compensate play without the wear. In case a roller fails or breaks, however, the
rollers binding. mast must be taken out of operation immediately.
Limits for such local wear cannot generally
be established as it depends on many factors

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8 Loading system
Mast

Roller clearance - fork carriage

in inner mast, type 189
Side clearance (AS)
The clearance is adjusted with shims, which are
fitted on the journal.
• Roller A, B: min 0 mm, max 0.2 mm at the clo-
sest point. In other cases 1.0 mm maximum
• Roller C: Number of shims same as A + X.
Dimension “X” is stamped into the fork carriage
channel (refer to drawing). For the compensation
of tolerances, the contact surface of journal C is
moved back a little in relation to A and B.
The following generally applies for 6-roller fork
carriages:
• The third roller pair C should only come to bear
fully when the upper rollers A come out of the
mast channel.
• When the rollers A and B contact their tracks,
roller C may have a smaller clearance (0 -
0.2 mm).
• Depending on the position of the journal, roller
C may be one size smaller than A and B.

Radial clearance - adjustment

Dimension “RS” Mast roller
Positions A,
B, C
over up to Part No.
see Parts
Catalogue
- 105.8 Roller size 1
105.81 106.1 Roller size 2
106.11 Roller size 3

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 Loading system 8
Mast

Roller clearance - middle and

inner mast, type 189
Illustrated: Support roller on inner mast to middle
mast

Lateral clearance setting

Dimension “RS” Support
rollers
ET No.
from to see Parts
Catalogue
Support roller
- 105.8
size 1
Support roller
105.81 106.1
size 2
Support roller
106.11 -
size 3

LATERAL CLEARANCE (LS)

The clearance dimension is adjusted with adjus-

ting shims which are slipped over the centring
pivot.
Adjusting clearance at narrowest point 0+0.2 mm.
Otherwise, it reaches a maximum of 1.0 mm at
the widest point. The clearance dimension is
adjusted with adjusting shims.

Outer Mast Roller Clearance,

Type 189
Illustrated: Support roller on inner mast to middle
mast

Dimension “RS” Support

rollers
ET No.
from to see Parts
Catalogue
Support roller
- 160.8
size 1
Support roller
160.81 161.1
size 2
Support roller
161.11 -
size 3

PERMISSIBLE LATERAL CLEARANCE

(AS)
The clearance dimension is adjusted with adjus- 1 Guide
ting shims which are slipped over the centring
pivot.

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8 Loading system
Mast

Adjusting clearance at narrowest point 0+0.2 mm.

Otherwise, it reaches a maximum of 1.0 mm at
the widest point.

Removal of slide pads - standard

mast
¾ Remove the circlips on the lift cylinders. If an
attachment is fitted, remove the upper hose
guide to prevent the hose from bending later.

¾ Extend the mast. Support the fork carriage or

secure with a chain between the outer mast
and fork carriage. Lower the inner mast to
approx. 100 mm, while supporting the cross
member at the bottom with a lift jack extended
approx. 200 mm.

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 Loading system 8
Mast

¾ Remove the mast supply lines and seal the

cylinders with sealing plugs. Hang the chain on
the outer mast cross member, lift the cylinder
out of the lower bracket with suitable aids (in
this case clamps of the attachment) and put it
down towards the truck centre.

¾ Lower the lift jack until the inner mast rests

on the outer mast cross member. Now the
slide pads and support rollers can be replaced
easily.

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8 Loading system
Mast

Removal of slide pads - duplex

mast
¾ Remove the circlips on the outer cylinders.
Extend the mast and secure the fork carriage
with a chain to the middle cross member.

¾ Lower the mast and catch the cross member of

the inner mast with the jack extended approx.
200 mm.

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 Loading system 8
Mast

¾ Remove the pipes at the lift cylinder and close

the ports of the outer cylinders at the top.

¾ Retract the cylinder completely and remove

the clamp fittings. Tilt the lift cylinder backward
and fix with a wedge, if necessary.

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8 Loading system
Mast

Removal of slide pads - triplex

mast
¾ If an hydraulic attachment is fitted, the outer
guide must be removed (hoses can remain
in the guide). Fasten the guide to the cross
member of the outer mast.

¾ Remove the guide on the right and attach it to

the upper cross member of the middle mast.

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 Loading system 8
Mast

¾ Extend the mast until the middle cross member

of the inner mast is at the level of the upper
cross member of the middle mast. Secure
both cross members with a chain at this height
and lower the fork carriage again.

¾ Remove the circlips on the outer cylinders and

disconnect the pipes at the upper fittings. Then
pressure-seal the cylinders with the appropri-
ate screw fittings, as they will be applied with
pressure again subsequently.

¾ Lift the mast with the hydraulic system of the

truck until the lower fittings on the middle mast
cylinders can be removed easily. After the
pipes have been removed, seal the cylinders
with appropriate sealing plugs.

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8 Loading system
Mast

¾ Completely lower the mast with the help of the

cable device and catch the middle mast with
the jack, which is extended approx. 200 mm.

¾ Remove the clamps on the outer cylinders.

Carefully pull the cylinders back and fix them
with a wedge, if necessary. The mast lines at
the bottom do not need to be removed.
¾ Use a car jack to lower the middle mast com-
pletely. Make sure that the outer cylinders
have enough clearance. Now the supporting
roller and the slide pad can be dismounted.

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 Loading system 8
Mast

Lift cylinder (outer) - removal and installation

1 Inner mast 4 Bracket

2 Circlip 5 Connecting line
3 Lift cylinder

CAUTION

When opening boost pressure lines, the inner

mast can lower, leading to severe injuries.
Secure the inner mast against lowering!

¾ Fully lower the mast and tilt it forward so that no

pressure is applied to the system and access
is ensured.
¾ Remove the circlip (2) at the top of the piston
rod of the lift cylinder (3).

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8 Loading system
Mast

¾ Disconnect the connecting line (5) at the bot-

tom of the lift cylinder and seal the hose ope-
ning with a dummy plug.
¾ Fully extend the inner mast (1) with the opera-
tional lift cylinder.
¾ Remove the bracket and hose clamps, if ne-
cessary.
¾ Unscrew the Allen screws at the base of the
cylinder.
¾ Lift the defective lift cylinder out.
¾ Installation of the lift cylinder (3) is in the re-
verse order of removal.
¾ Install the lift cylinder.
¾ Remove the safety device securing the inner
mast and lower the inner mast.
¾ Install the circlip (2).
¾ Connect the connecting line (5).
¾ Bleed the hydraulic circuit.

Lift cylinder (centre) - removal and installation

¾ Raise the fork carriage approx. 10 cm with the

working hydraulic system.

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 Loading system 8
Mast

¾ Secure the fork carriage in this position to pre-

vent it from lowering.
¾ Actuate the working hydraulic system so that
the centre lift cylinder retracts again and the
chains are loose.
¾ Remove the clamps on the guide pulleys of the
chains.
¾ Remove the chains from the guide pulleys.
¾ Remove the line at the base of the lift cylinder.
¾ Remove the retaining clamp of the cylinder.
¾ Remove the lift cylinder.

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8 Loading system
Mast

Lift cylinder - sealing

¾ Remove the clamp and reflection pulley on the
centre lift cylinder. On duplex and triplex masts
remove the fitting to the centre lift cylinder on
the outer cylinders.
¾ Clamp the cylinder into a vice at the base.
¾ Heat the cylinder head (3) (it is secured with
Loctite), and unscrew it from the cylinder tube
(5) with a pin spanner.
¾ Remove the scraper (1), the U-cup packing
(2), and the O-ring (4) from the cylinder head
(3).
¾ Install a new set of seals.
¾ Mount the cylinder head (3) and pulley with
Loctite 243.

NOTE

The piston rod consists of a tube into which the

piston cover is fitted at the upper end and made
into a non-detachable unit with the piston tube
with the circlip. In the event of an oil loss in the
upper piston cover, the lower piston cover is leaky
and must be dismantled, cleaned and re-installed
with Loctite 243.

Lift cylinder - sealing

CAUTION

When carrying out the following services, the ser-

vice engineer can come in contact with hydraulic
system oil.
Wear personal protective gear.

Replace the seal at the base of the cylin-

der.
Prerequisite:
The lift cylinder is removed and the seal kit is at 1 Scraper
hand. 2 U-cup packing
3 Cylinder head
4 O-ring
5 Cylinder tube
6 Piston rod
7 Bleed screw

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 Loading system 8
Mast

¾ Remove the 2 hex head screws at the base of

the cylinder.
¾ Remove the base of the cylinder.
¾ Replace the seal.
¾ Install the base of the cylinder.

Tilt angle sensor - adjustment

DANGER
A limitation of the backward tilt may be given
by an attachment or/and special tyres.
The actual load capacity if an attachment is fitted
and the required limited backward tilt must be
calculated with the aid of the software program
“TRALA”.

DANGER

Disregarding the tilt angle limitation can re-

sult in the truck tipping over.
The tilt angle sensor must be adjusted on the
unladen truck.
Note any possible tilt angle limitations.
Backward tilt limitations are specified according
to tonnage, type of mast, height of lift, mounted
implement and tyres.

Prerequisites

A laptop with the “Pathfinder” software is required

for the adjustment (calibration) of the tilt angle
sensor.

Reference points - marking

¾ Draw a line on the face plate, which runs paral-
lel to column A at a distance of 87 ± 2 mm from
the centre point of the M8 screw.
¾ Draw another line on the face plate, which runs
horizontally at a distance of 314 ± 2 mm from
the wing.
The intersection of both lines is the reference
point on the truck side.

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8 Loading system
Mast

¾ Mark the reference point on the mast side at a

distance of 939 ± 2 mm from the lower end and
100 ± 2 mm from the side face of the external
mast profile.

Tilt angle sensor - calibration

CAUTION

When the mast is tilted back towards its mechani-

cal stop, it could contact the wiper arm if the truck
is fitted with a front windscreen and wiper.
Remove the wiper arm.

¾ Start the diagnostic software “Pathfinder”.

¾ Go to the window “Adjustments (calibration of
the tilt angle sensor)”.
¾ Tilt the mast back against the mechanical stop.
¾ Measure and record distance X0 (basic dimen-
sion) between the truck-side and mast-side
reference points.
¾ Tilt the mast forward by dimension XR (back-
ward tilt dimension) from the mechanical stop.
Refer to the table “Nominal backward tilt” below
for dimension XR.

H 40
Nominal standard H 40
All other
back- LH 3100 standard
masts
ward tilt1 to LH LH 3000
of type
in 3500 with
189
degrees with OHG OHG 3 - 6
3 to 6
XR in XR in XR in
(mm) (mm) (mm)
0.0° 143 137 130
0.5° 136 130 123
1.0° 129 123 116
1.5° 122 116 109
2.0° 115 109 102
2.5° 108 102 95
3.0° 101 95 88
3.5° 94 88 82
4.0° 87 82 75
4.5° 80 75 68
5.0° 73 68 61
5.5° 66 61 54
6.0° 59 54 46

1 Backward tilt limitations are specified according to tonnage, type of mast, height of lift, mounted implement and tyres.

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 Loading system 8
Mast

H 40
Nominal standard H 40
All other
back- LH 3100 standard
masts
ward tilt1 to LH LH 3000
of type
in 3500 with
189
degrees with OHG OHG 3 - 6
3 to 6
6.5° 52 46 39
7.0° 45 39 32
7.5° 38 32 25
8.0° 31 25 18
8.5° 24 18 172
9.0° 23 173 -

¾ Measure the distance between truck-side and

mast-side reference points.
The distance should be X0 + XR. The value XR is
required by the diagnostic software.
¾ Enter the value.
¾ Calibrate the rear electronic stop.
¾ Press the “Done” button in the diagnosis win-
dow.

2 Standard factory setting if the limitation of the backward tilt is not specified.
3 Standard factory setting if the limitation of the backward tilt is not specified.

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8 Loading system
Mast

¾ Tilt mast forward from its mechanical limit stop

by the distance XV (forward tilt dimension).
For XV see the table below.
¾ Measure the distance between truck-side and
mast-side reference points.
The distance should be X0 + XV.
¾ Enter the value XV in the diagnostic software.
¾ Calibrate the front electronic stop.
¾ Press the “Done” button in the diagnosis win-
dow.

H 40
Nominal standard H 40
All other
forward- LH 3100 standard
masts
tilt4 to LH LH 3000
of type
in 3500 with
189
degrees with OHG OHG 3 - 6
3 to 6
XV in XV in XV in
(mm) (mm) (mm)
0.0° 126 120 113
0.5° 133 127 120
1.0° 140 134 127
1.5° 147 141 134
2.0° 154 148 141
2.5° 161 155 148
3.0° 168 162 155
3.5° 175 169 162
4.0° 181 176 169
4.5° 188 183 176
5
5.0° 195 189 182

Tilt cylinder

4 Backward tilt limitations are specified according to tonnage, type of mast, height of lift, mounted implement and tyres.
5 Standard factory setting

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 Loading system 8
Mast

Thread reaches for mechanical adjust-

ment of the tilt cylinders

CAUTION
If the adjustment of the limitation of the tilt angle
is incorrect, the guaranteed truck stability can be
greatly reduced and the truck can tip over when
laden and the mast extended.
In the event of repairs, always be sure the thread
reach of the piston rod into the swivel is correct.
The thread reach depends on the truck type, the
lift height and the mast type.

Thread on piston rod M20 x 1.5

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8 Loading system
Mast

Height of
Vehicle Mast Thread
lift
(type) (type) reach
in (mm)
2600 33 mm
3000 33 mm
6
3000 51 mm
3100 37 mm
7
3100 48 mm
3200 46 mm
8
3200 33 mm
3300 33 mm
9
3300 38 mm
3400 33 mm
10
3400 42 mm
3500 34 mm
11
3500 43 mm
3600 33 mm
3700 33 mm
3800 36 mm
3900 42 mm
H 40 Standard
4000 45 mm
4100 45 mm
4200 44 mm
4300 40 mm
4400 33 mm
4500 49 mm
4600 38 mm
4700 33 mm
4800 39 mm
4900 50 mm
5000 33 mm
5100 34 mm
5200 33 mm
5300 41 mm
5400 33 mm
5900 33 mm
6300 33 mm

6 With OHG 3 to 6
7 With OHG 3 to 6
8 With OHG 3 to 6
9 With OHG 3 to 6
10 With OHG 3 to 6
11 With OHG 3 to 6

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 Loading system 8
Mast

Height of
Vehicle Mast Thread
lift
(type) (type) reach
in (mm)
2630 33 mm
3030 33 mm
3130 33 mm
3230 41 mm
3330 48 mm
3430 33 mm
3530 33 mm
3630 33 mm
3730 39 mm
3830 43 mm
3930 44 mm
H 40 Duplex 4030 43 mm
4130 40 mm
4230 34 mm
4330 33 mm
4430 44 mm
4530 32 mm
4630 41 mm
4730 52 mm
4830 52 mm
4930 52 mm
5030 52 mm
5130 52 mm

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8 Loading system
Mast

Height of
Vehicle Mast Thread
lift
(type) (type) reach
in (mm)
3925 33 mm
4525 33 mm
4675 33 mm
4765 41 mm
4915 48 mm
5065 33 mm
5215 33 mm
5365 33 mm
5515 39 mm
5715 44 mm
5865 43 mm
H 40 Triplex
6015 40 mm
6165 34 mm
6315 33 mm
6465 44 mm
6615 32 mm
6765 41 mm
6915 52 mm
7065 52 mm
7215 52 mm
7365 52 mm
7515 52 mm

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 Loading system 8
Mast

Height of
Vehicle Mast Thread
lift
(type) (type) reach
in (mm)
2600 37 mm
3000 37 mm
3100 48 mm
3200 33 mm
3300 36 mm
3400 40 mm
3500 41 mm
3600 41 mm
3700 37 mm
3800 49 mm
3900 33 mm
4000 33 mm
4100 33 mm
H 45/50 Standard 4200 33 mm
4300 33 mm
4400 46 mm
4500 37 mm
4600 33 mm
4700 42 mm
4800 33 mm
4900 35 mm
5000 34 mm
5100 37 mm
5200 40 mm
5300 33 mm
5400 46 mm
5900 40 mm
6300 40 mm

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8 Loading system
Mast

Height of
Vehicle Mast Thread
lift
(type) (type) reach
in (mm)
2630 33 mm
3030 33 mm
3130 44 mm
3230 33 mm
3330 33 mm
3430 35 mm
3530 35 mm
3630 43 mm
3730 49 mm
3830 33 mm
3930 33 mm
H 45/50 Duplex 4030 33 mm
4130 50 mm
4230 45 mm
4330 37 mm
4430 40 mm
4530 45 mm
4630 33 mm
4730 35 mm
4830 35 mm
4930 35 mm
5030 35 mm
5130 35 mm

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 Loading system 8
Mast

Height of
Vehicle Mast Thread
lift
(type) (type) reach
in (mm)
3925 33 mm
4525 33 mm
4675 44 mm
4765 33 mm
4915 33 mm
5065 35 mm
5215 35 mm
5365 43 mm
5515 49 mm
5715 33 mm
5865 33 mm
H 45/50 Triplex
6015 50 mm
6155 45 mm
6315 37 mm
6465 40 mm
6615 45 mm
6765 33 mm
6915 35 mm
7065 35 mm
7215 35 mm
7365 35 mm
7515 35 mm

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8 Loading system
Mast

Tilt cylinder - removal

1 Hex head screw 11 Cylinder head

2 Rubber bush 12 O-ring 40x3-P90
3 Intermediate piece 13 Circlip
4 Cylinder tube 14 Scraper
5 Hexagon nut M18 x 1.5-10 15 Threaded rod (extension)
6 Guide ring 16 Hex head screw
7 Piston cup 17 Clamping piece
8 Piston 18 Swivel
9 Piston rod 19 Rubber bush
10 U-cup packing 20 Clamping piece

CAUTION

The tilt cylinders are installed on the overhead

guard and not accessible without aids.
The services on the built-in tilt cylinders can only
be carried out on a suitable ladder.

CAUTION

When working below leaky tilt cylinders, the ser-

vice engineer can come in contact with hydraulic
system oil.
Wear protective clothing.

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 Loading system 8
Mast

¾ Lower the fork carriage and tilt the mast back

by approx. 2°.
¾ Use a crane to secure the mast against tilting
forward.
¾ Remove the hydraulic fittings at the front and
the rear of the tilt cylinder, unscrew the banjo
bolts.
¾ Unscrew the hex head bolt at the front tilt cylin-
der mount.
¾ Remove the inner and outer clamping piece.
¾ Unscrew the hex head bolt at the rear tilt cylin-
der mount and take the adapter piece off.
¾ Take the tilt cylinder down from the truck.

NOTE

Tilting the mast back by approx. 2° relieves the

rubber bushes of the tilt cylinder mounts.

Tilt cylinder - sealing

Prerequisite:
The tilt cylinder is removed. Seal kit at hand.

NOTE

The seal kit set consists of a guide ring, piston

seal, grooved ring, O-ring and scraper.

¾ Clamp the tilt cylinder into a vice with approp-

riate jaws.
¾ Loosen the scraper with a screwdriver and pull
it off.
¾ To release the circlip, push the cylinder head
back by approx. 10 mm.
¾ Release the circlip from the groove and re-
move it.
¾ If necessary, remove the burr formed by the
circlip with the help of a three-square scraper.
¾ Pull out the piston rod along with the cylinder
head. When doing this, the remaining hydrau-
lic oil in the cylinder will run out through the
front port. Put an appropriate receptacle un-
derneath.
¾ Loosen the clamping screw at the swivel and
unscrew it from the threaded rod.
¾ Slightly lubricate the sealing elements and
replace them.
¾ Insert the piston rod into the cylinder tube.

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8 Loading system
Mast

¾ Install the cylinder head. Please make sure

that the groove of the cylinder head is aligned
with the thread of the front port, but do not slide
the cylinder head in too far.
¾ Mount the circlip.

NOTE

When the hydraulic line is connected, the cylinder

head is fixed in position with the help of the banjo
bolt.

¾ Install the scraper with Loctite no. 270.

¾ Screw the swivel on the threaded rod, taking
care to achieve the correct mounting dimen-
sion.
¾ Tighten the locking screw to a torque of Ma =
80 Nm.

Tilt cylinder - installation

¾ Screw the tilt cylinder with adapter piece and
hex head bolt on the rear tilt cylinder mount.
Torque for rear hex head bolt: Ma = 275 Nm
¾ Put the inner and outer clamping piece onto
the front rubber bush.

NOTE

The oval opening of the rubber bush must be in

vertical position.

¾ Fasten to the front tilt cylinder mount on the

mast with the hex head bolt.
Torque for front hex head bolt: Ma = 275 Nm
¾ Install the hydraulic hoses with banjo bolts.
¾ Carry out a functional check.

Hose reel - removal, hose

change, sealing, installation

WARNING
The hose reel is prestressed by spring force.
For this reason it is essential to follow the instruc-
tions.

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 Loading system 8
Mast

NOTE
The hose reel is located underneath the floor
plate in the front area of the frame. The descrip-
tion refers to a single auxiliary hydraulic system.
As far as trucks with two hose reels must con-
cerned (double accessory hydraulic system), the
instructions must be carried out for both hose re-
els.

Hose reel - removal

NOTE

Before the floor plate is taken out, pull off the

plug to the traction potentiometer and unhook the
brake cable assembly at the brake valve.

¾ Open the bonnet

¾ Take the floor mat out
¾ Remove the floor plate

CAUTION

The hose reel is prestressed by spring force. If

the hose reel is removed without first securing it,
the spring will relive spontaneously, which can
lead too severe injuries.
Make sure the pawl engages in one of the cams
provided on the circumference of the hose reel so
the hose reel does not unwind accidentally.

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8 Loading system
Mast

¾ Lock the hose reel in the prestressed condition

by pivoting the pawl in the direction of the hose
reel. When doing so, unwind the hose reel a
little. This keeps the hose loose in the locked
condition.

¾ Release the double hose at the connection to

the mast.
¾ Disconnect the supply line from the control
valve to the hose reel.
¾ Unscrew the front hexagon head screws (2
items) at the hose reel holder.
The hexagon head screws are located at the front
part of the holder above the pulleys.
¾ Loosen the two hexagon head screws at the
side of the hose reel holder.
¾ Unscrew the rear hexagon head screws
(2 items) at the hose reel holder.
¾ Release the hose reel from the holder.
¾ To do so, unscrew the Allen screws (2) at the
side of the hose reel holder.
¾ Take the hose reel holder out.
¾ Take the hose reel out.

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 Loading system 8
Mast

Hose change
¾ Clamp the hose reel into a vice and loosen the
4 Allen screws.
¾ Remove the cover of the hose reel.
¾ Unwind the double hose and replace it with a
new double hose.
¾ Wind up the double hose and fasten the hose
reel cover with the 4 Allen screws.
¾ Install the hose reel with the holder into the
truck.
¾ Carry out a functional check.

Hose reel - sealing

¾ Clamp the hose reel into a vice.
¾ Pull the double hose out until the pawl is relie-
ved.
¾ Swivel the pawl out of the cam while holding
the double hose fast.
The hose reel is still taut.
¾ Hold the double hose fast and carefully release
the hose reel against the force of the spring.
This will pull the double hose somewhat further
on the hose reel.
¾ Unscrew a hexagon head screw (5).
¾ Remove the cover with the O-ring.
¾ Unscrew 2 Allen screws (2) and remove the
holder and the pawl.
¾ Pull the shaft of the hose reel out.
¾ Replace the shaft sealing ring (3) on the shaft.
¾ Take the three O-rings with support rings (6)
out and replace them.
¾ Replace the two O-rings (1) at the holder with
a pawl.

Service Training – 394 804 2401 EN – 01/2005 8-33

8 Loading system
Mast

Hose reel - installation

¾ Slightly lubricate the O-rings, the support rings
and the shaft sealing ring.
¾ During the installation, make sure that the ten-
sioning spring of the hose reel is inserted into
the groove of the shaft.
¾ Mount the holder with the pawl.
¾ Clamp the hose reel into a vice.
¾ Mount the cover with a new O-ring (4).

CAUTION

The hose reel is prestressed by spring force. A

spontaneous release of the spring can lead to
severe personal injuries.
The following activities must be carried out with
utmost care.

¾ Preload the hose reel.

¾ To do so, turn the hose reel manually against
the force of the spring.
¾ Lock the pawl at the circumference of the hose
reel and preload the hose reel by 5 to 6 turns
Starting from the manufacturing date 06/2002
see type plate of hose reel - preload by 8 turns).
¾ Install the hose reel with the holder into the
truck.
¾ Carry out a functional check.

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 g 0
Index

A Brake light . . . . . . . . . . . . . . . . . . . . . . . . 9-16

higher . . . . . . . . . . . . . . . . . . . . . . . . 9-18
Abbreviations
Brake pedal switch . . . . . . . . . . . . . . 9-6, 9-12
measurements . . . . . . . . . . . . . . . . . . 2-20
start inhibit . . . . . . . . . . . . . . . . . 9-4, 9-10
Actual speed sensor . . . . . . . . . . . . . 9-6, 9-12
Brake release valve . . . . . . . . . . . . . . . . . . 4-4
setting instructions . . . . . . . . . . . . . . . 1-63
bleeding . . . . . . . . . . . . . . . . . . . . . . . 4-6
Air conditioning
method of operation . . . . . . . . . . . . . . . 4-5
fan motor . . . . . . . . . . . . . . . . . . . . . . 9-22
Brake system
pressure switch . . . . . . . . . . . . . . . . . 9-22
check . . . . . . . . . . . . . . . . . . . . . . . . . 4-13
with heater . . . . . . . . . . . . . . . . . . . . . 9-22
Brake valve . . . . . . . . . . . . . . . . . . . . . . . 4-10
Air-cushioned seat
control valve, tilting function . . . . . . . . . 7-3
compressor motor . . . . . . . . . . . . . . . 9-26
method of operation . . . . . . . . . . . . . . 4-12
Air-fuel ratio
switching function . . . . . . . . . . . . . . . . 4-13
integrator . . . . . . . . . . . . . . . . . . . . . . 1-43
Bucket tappets
lambda . . . . . . . . . . . . . . . . . . . . . . . 1-41
check . . . . . . . . . . . . . . . . . . 1-118, 1-119
stoichiometric . . . . . . . . . . . . . . . . . . 1-40
Bypass valve . . . . . . . . . . . . . . . . . . . . . . 2-13
Antenna . . . . . . . . . . . . . . . . . . . . . . . . . . 9-24
GPRS . . . . . . . . . . . . . . . . . . . . . . . . 9-20 C
Area valve . . . . . . . . . . . . . . . . . . . . . . . . 1-30
Cable
Auxiliary hydraulics
service brake . . . . . . . . . . . . . . . . . . . . 4-8
functional description . . . . . . . . . . . . . . 7-3
Camshaft . . . . . . . . . . . . . . . . . . 1-118, 1-120
Axle suspension
chain . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8
security . . . . . . . . . . . . . . . . . . . . . . . . 3-1
installation . . . . . . . . . . . . . . . . . . . . 1-120
B removal . . . . . . . . . . . . . . . . . . . . . . 1-120
Camshaft adjuster . . . . . . . . . . . . . . . . . . 1-12
Backfiring
exhaust . . . . . . . . . . . . . . . . . . . . . . . 1-17
cause . . . . . . . . . . . . . . . . . . . . . . . . 1-82
intake . . . . . . . . . . . . . . . . . . . . . . . . 1-16
Backward tilt
mark . . . . . . . . . . . . . . . . . . . . . . . . . 1-16
angle tables . . . . . . . . . . . . . . . . . . . . 8-18
Camshaft adjustment . . . . . . . . . . . . . . . . . 9-8
Balance valve for recirculating oil . . . . . . . . 7-1
Camshaft chain
Belt pulley
install the slide rail . . . . . . . . . . . . . . . 1-13
oil seal . . . . . . . . . . . . . . . . . . . . . . . 1-102
installation . . . . . . . . . . . . . . . . . . . . . 1-14
Black smoke
Camshaft drive
excessive, cause . . . . . . . . . . . . . . . . 1-82
install the camshaft chain . . . . . . . . . . 1-14
prevention . . . . . . . . . . . . . . . . . . . . . 1-59
Camshaft position
Blue smoke
correct . . . . . . . . . . . . . . . . . . . . . . . . 1-98
cause . . . . . . . . . . . . . . . . . . . . . . . . 1-82
Camshaft sprocket . . . . . . . . . . . . . . . . . 1-118
Bolts
Chain tensioner
torques . . . . . . . . . . . . . . . . . . . . . . 1-112
ratchet . . . . . . . . . . . . . . . . . . . . . . . . 1-14
Boost pressure limitation
Change oil filter . . . . . . . . . . . . . . . . . . . . 1-47
valve for . . . . . . . . . . . . . . . . . . . . . . . 9-14
Characteristic map
Brake cable
start of injection . . . . . . . . . . . . . . . . . 1-77
parking brake . . . . . . . . . . . . . . . . . . . . 4-7
Characteristic map for smoke . . . . . . . . . . 1-69
Brake cables
Charge pressure control
adjustment . . . . . . . . . . . . . . . . . . . . . . 4-6
load cell . . . . . . . . . . . . . . . . . . . . . . 1-132
location . . . . . . . . . . . . . . . . . . . . . . . . 4-7

Service Training – 394 804 2401 EN – 01/2005 1

0 g
Index

Charge pressure limitation . . . . . . . . . . . 1-132 Control valve

solenoid valve . . . . . . . . . . . . . . . . . 1-126 balance valve . . . . . . . . . . . . . . . . . . . . 7-3
suction pipe pressure . . . . . . . . . . . . 1-126 balance valve for recirculating oil . . . . . 7-1
Circuit diagram emergency lowering . . . . . . . . . . . . . . . 7-2
air flow sensor . . . . . . . . . . . . . . 9-7, 9-13 function lifting . . . . . . . . . . . . . . . . . . . . 7-2
coolant temperature sensor . . . . 9-7, 9-13 introduction . . . . . . . . . . . . . . . . . . . . . 7-1
engine speed sensor . . . . . . . . . 9-7, 9-13 PLV . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-1
sensor for control collar . . . . . . . 9-7, 9-13 pressure adjustment . . . . . . . . . . . . . . 7-4
sensor for inlet pipe pressure . . . 9-7, 9-13 pressure reducing valve setting instruc-
sensor for needle lift . . . . . . . . . . 9-7, 9-13 tions . . . . . . . . . . . . . . . . . . . . . . . 7-4
CO content release valve . . . . . . . . . . . . . . . . . . . . 7-1
adjustment of full load mixture . . . . . . . 1-38 tilting . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
adjustment of idle mixture . . . . . . . . . . 1-38 tilting brake valve . . . . . . . . . . . . . . . . . 7-3
Codes Coolant
composite instrument . . . . . . . . . . . . . 0-14 additives . . . . . . . . . . . . . . . . . . . . . 1-136
LTC, lift controller . . . . . . . . . . . . . . . . 0-12 antifreeze . . . . . . . . . . . . . . . . . . . . 1-137
LTC, traction control . . . . . . . . . . . . . . . 0-9 boiling point . . . . . . . . . . . . . . . . . . . 1-137
Cold start valve . . . . . . . . . . . . . . . . . . . . 9-12 concentration . . . . . . . . . . . . . . . . . . 1-137
Composite instrument draining . . . . . . . . . . . . . . . . . . . . . . . 1-23
display . . . . . . . . . . . . . . . . . . . . . . . . . 6-5 mixing ratio . . . . . . . . . . . . . . 1-24, 1-137
Compression return-flow pump . . . . . . . . . . . . . . . . . 9-8
check . . . . . . . . . . . . . . . . . . . . . . . . 1-113 Coolant additive
readings . . . . . . . . . . . . . . . . . 1-3, 1-113 brand . . . . . . . . . . . . . . . . . . . . . . . . . 1-23
test . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 concentration . . . . . . . . . . . . . . . . . . . 1-24
Compression ratio . . . . . . . . . . . . . . . . . . 1-46 Coolant temperature
engine VW BMF . . . . . . . . . . . . . . . . . . 1-1 sensor . . . . . . . . . . . . . . . . . . . . . . . . 1-49
Compressor motor Coolant thermostat . . . . . . . . . . . . . . . . . 1-133
air-cushioned seat . . . . . . . . . . . . . . . 9-26 housing disassembly . . . . . . . . . . . . . 1-25
Control sleeve installation . . . . . . . . . . . . . . . . . . . . 1-134
angle of rotation . . . . . . . . . . . . . . . . . 1-60 removal . . . . . . . . . . . . . . . . . . . . . . 1-133
Control sleeve position Cooling system
sensor . . . . . . . . . . . . . . . . . . . . . . . . 1-60 hose routing . . . . . . . . . . . . . . . . . . . . 1-22
Control unit Corrective functions . . . . . . . . . . . . . . . . 1-141
soot filter . . . . . . . . . . . . . . . . . . . . . . 9-24 Crankshaft position . . . . . . . . . . . . . . . . . 1-97
Current regulator
glow plugs . . . . . . . . . . . . . . . . . . . . . 9-24
Cylinder head
bolts, torques . . . . . . . . . . . . . . . . . . 1-112
check for flatness . . . . . . . . . . . . . . . 1-110
check piston position . . . . . . . . . . . . 1-110
compression readings . . . . . . . . . . . 1-113
identification . . . . . . . . . . . . . . . . . . 1-111
overview . . . . . . . . . . . . . . . . . . . . . 1-109
removal . . . . . . . . . . . . . . . . . . . . . . 1-111

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 g 0
Index

Cylinder head BMF Engine control unit

check for flatness . . . . . . . . . . . . . . . . . 1-5 adaptation possibilities . . . . . . . . . . . 1-139
removal and installation . . . . . . . . . . . . 1-4 replacement . . . . . . . . . . . . . . . . . . . 1-139
replacement . . . . . . . . . . . . . . . . . . . . . 1-9 safety concept . . . . . . . . . . . . . . . . . 1-141
Cylinder head bolts Engine electronics
length . . . . . . . . . . . . . . . . . . . . . . . . 1-11 overview . . . . . . . . . . . . . . . . . . . . . . . 0-6
sequence . . . . . . . . . . . . . . . . . . . . . . . 1-9 Engine number
torque . . . . . . . . . . . . . . . . . . . . . . . . 1-11 structure . . . . . . . . . . . . . . . . . . . . . . 1-46
Cylinder head cover Engine overheating
removal . . . . . . . . . . . . . . . . . . . . . . . 1-19 cause . . . . . . . . . . . . . . . . . . . . . . . . 1-82
Cylinder head gasket . . . . . . . . . . . . . . . . 1-98 Exhaust gases
carbon monoxide . . . . . . . . . . . . . . . . 1-39
D composition . . . . . . . . . . . . . . . . . . . . 1-39
Data block
standardised . . . . . . . . . . . . . . . . . . 1-148 F
test procedure . . . . . . . . . . . . . . . . . 1-149 Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-24
Dead time Fan drive . . . . . . . . . . . . . . . . . . . . . . . . . 2-17
lambda sensor . . . . . . . . . . . . . . . . . . 1-43 Fan motor
Diagnosis air conditioning . . . . . . . . . . . . . . . . . . 9-22
starting . . . . . . . . . . . . . . . . . . . . . . 1-141 Fault
Diesel exhaust gases code number . . . . . . . . . . . . . . . . . . 1-143
hydrocarbons . . . . . . . . . . . . . . . . . . . 1-39 table . . . . . . . . . . . . . . . . . . . . . . . . 1-143
nitrogen oxide . . . . . . . . . . . . . . . . . . 1-39 Fault finding . . . . . . . . . . . . . . . . . . . . . . 1-141
oxidants . . . . . . . . . . . . . . . . . . . . . . . 1-39 Fault tree
Dip beam . . . . . . . . . . . . . . . . . . . . . . . . . 9-16 brake system . . . . . . . . . . . . . . . . . . . 4-13
Discharge . . . . . . . . . . . . . . . . . . . . . . . . 2-14 travel drive . . . . . . . . . . . . . . . . . . . . . 2-21
Discharging valve . . . . . . . . . . . . . . . . . . 2-15 Film sensor . . . . . . . . . . . . . . . . . . . . . . 1-123
Display Flame sensor
fault codes . . . . . . . . . . . . . . . . . . . . . . 0-9 soot filter . . . . . . . . . . . . . . . . . . . . . . 9-24
Double potentiometer Flasher . . . . . . . . . . . . . . . . . . . . . . . . . . 9-16
electronic truck speed controller . 9-6, 9-12 Flywheel fastener . . . . . . . . . . . . . . . . . . 1-102
mast vertical . . . . . . . . . . . . . . . . . . . . 9-6 Fork carriage
mast vertical position . . . . . . . . . . . . . 9-12 roller clearance . . . . . . . . . . . . . . . . . . 8-4
Drive chain Forward tilt
tolerances . . . . . . . . . . . . . . . . . . . . . 1-12 angle tables . . . . . . . . . . . . . . . . . . . . 8-20
Drop in performance Freewheel pulley
cause . . . . . . . . . . . . . . . . . . . . . . . . 1-82 installation . . . . . . . . . . . . . . . 1-26, 1-138
removal . . . . . . . . . . . . . . . . . 1-26, 1-138
E Fuel
EDC . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-47 metering . . . . . . . . . . . . . . . . . . . . . . 1-67
self-test . . . . . . . . . . . . . . . . . . . . . . 1-141 shut-off valve . . . . . . . . . . . . . . 1-72, 9-14
Electronic Diesel Control . . . . . . . . . . . . . 1-47 Fuel consumption
Electronic truck speed controller excessive, cause . . . . . . . . . . . . . . . . 1-82
double potentiometer . . . . . . . . . 9-6, 9-12 Fuel quantity positioner . . . . . . . . . 1-67, 1-70
Emergency stop . . . . . . . . . . . . . . . . . . . . 2-11 control . . . . . . . . . . . . . . . . . . . . . . . . 1-70

Service Training – 394 804 2401 EN – 01/2005 3

0 g
Index

Fuel temperature Hydraulic oil

sensor . . . . . . . . . . . . . . . . . . . . . . . . 1-53 temperature sensor . . . . . . . . . . 9-6, 9-12
Fuses
layout . . . . . . . . . . . . . . . . . . . . . . . . . 6-2
I
Idle
G governing . . . . . . . . . . . . . . . . . . . . . 1-68
Gas failure Ignition switch . . . . . . . . . . . . . . . . . 9-4, 9-10
cut-off . . . . . . . . . . . . . . . . . . . . . . . . 1-34 Immobilizer
Glow plug . . . . . . . . . . . . . . . . . . . 1-65, 9-14 adaptation possibilities . . . . . . . . . . . 1-139
current regulator . . . . . . . . . . . . . . . . 9-24 malfunctions . . . . . . . . . . . . . . . . . . 1-139
soot filter . . . . . . . . . . . . . . . . . . . . . . 9-24 replacement . . . . . . . . . . . . . . . . . . . 1-139
GPRS . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-20 Injection
antenna . . . . . . . . . . . . . . . . . . . . . . . 9-20 rate . . . . . . . . . . . . . . . . . . . . . . . . . . 1-47
timing . . . . . . . . . . . . . . . . . . . . . . . . 1-47
H Injection pump
Hazard warning flasher filling with fuel . . . . . . . . . . . . . . . . . . . 1-97
higher . . . . . . . . . . . . . . . . . . . . . . . . 9-18 installation . . . . . . . . . . . . . . . . . . . . . 1-96
Hazard warning flasher system . . . . . . . . . 9-16 overview . . . . . . . . . . . . . . . . . . . . . . 1-93
Heater removal . . . . . . . . . . . . . . . . . . . . . . . 1-94
with air conditioning . . . . . . . . . . . . . . 9-22 Injection pump sprocket . . . . . . . . . . . . . . 1-98
Heating system Injection quantity
post-heating . . . . . . . . . . . . . . . . . . . . 1-64 calculation . . . . . . . . . . . . . . . . . . . . . 1-51
preheating . . . . . . . . . . . . . . . . . . . . . 1-64 Injection start
HMF 135 -02 . . . . . . . . . . . . . . . . . . . . . . 2-24 valve for . . . . . . . . . . . . . . . . . . . . . . . 9-14
Hose layout Injection system
auxiliary hydraulics, duplex mast . . . . . 7-14 overview . . . . . . . . . . . . . . . . . . . . . . 1-85
auxiliary hydraulics, standard mast . . . 7-13 supply voltage . . . . . . . . . . . . . . . . . . 1-86
control pressure supply . . . . . . . . . . . . 7-9 Injection timing device . . . . . . . . . . . . . . . 1-72
for lifting . . . . . . . . . . . . . . . . . . . . . . . 7-10 start of injection . . . . . . . . . . . . . . . . . 1-73
for tilting . . . . . . . . . . . . . . . . . . . . . . . 7-11 Intake air
oil reservoir return flow . . . . . . . . . . . . 7-12 pressure sensor . . . . . . . . . . . . . . . . . . 9-8
Hose reel temperature sensor . . . . . . . . . . . . . . . 9-8
hose change . . . . . . . . . . . . . . . . . . . 8-33 Integrator . . . . . . . . . . . . . . . . . . . . . . . . . 1-43
installation . . . . . . . . . . . . . . . . . . . . . 8-34 Interior lighting . . . . . . . . . . . . . . . . . . . . . 9-22
removal . . . . . . . . . . . . . . . . . . . . . . . 8-31
sealing . . . . . . . . . . . . . . . . . . . . . . . . 8-33 K
Hydr. pump control Knocking
emergency stop . . . . . . . . . . . . . . . . . 2-11 cause . . . . . . . . . . . . . . . . . . . . . . . . 1-82
method of operation . . . . . . . . . . . . . . 2-10
overview . . . . . . . . . . . . . . . . . . . . . . . 2-5
L
Hydr. zero position Lambda
adjustment . . . . . . . . . . . . . . . . . . . . . 2-11 air-fuel ratio . . . . . . . . . . . . . . . . . . . . 1-41
Hydraulic motor Lambda control . . . . . . . . . . . . . . . . . . . . 1-40
HMF 135 -02 . . . . . . . . . . . . . . . . . . . 2-24 method of operation . . . . . . . . . . . . . . 1-42
stoichiometric . . . . . . . . . . . . . . . . . . 1-40

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Index

Lambda probe . . . . . . . . . . . . . . . . . . . . . . 9-8 LTC modules

Lambda sensor overview and position of modules . . . . . 0-5
control range . . . . . . . . . . . . . . . . . . . 1-44
dead time . . . . . . . . . . . . . . . . . . . . . . 1-43
M
excess fuel . . . . . . . . . . . . . . . . . . . . . 1-41 Mass air flow sensor . . . . . . . . . . . . . . . . 1-123
heated . . . . . . . . . . . . . . . . . . . . . . . . 1-42 Mast
method of operation . . . . . . . . . . . . . . 1-41 adjusting lift chain . . . . . . . . . . . . . . . . . 8-2
operating temperature . . . . . . . . . . . . 1-41 adjustment of roller clearance . . . . . . . . 8-3
response time . . . . . . . . . . . . . . . . . . 1-41 identification . . . . . . . . . . . . . . . . . . . . 8-1
voltage signal . . . . . . . . . . . . . . . . . . . 1-42 Mast vertical
Layout double potentiometer . . . . . . . . . 9-6, 9-12
fuses . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 Metering pump
relay . . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 soot filter . . . . . . . . . . . . . . . . . . . . . . 9-24
Leakage test Mixer
LPG system . . . . . . . . . . . . . . . . . . . . 1-35 basic setting . . . . . . . . . . . . . . . . . . . . 1-36
Lift cylinder throttle plate stop screw . . . . . . . . . . . 1-37
removal and installation . . . . . . . . . . . 8-13 Multiple disc brake
replace seal . . . . . . . . . . . . . . . . . . . . 8-16 releasing . . . . . . . . . . . . . . . . . . . . . . 2-14
sealing . . . . . . . . . . . . . . . . . . . . . . . . 8-16
N
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . 9-16
higher . . . . . . . . . . . . . . . . . . . . . . . . 9-18 Needle stroke
Load cell sensor . . . . . . . . . . . . . . . . . . . . . . . . 1-58
charge pressure control . . . . . . . . . . 1-132 Noise
Load sensor . . . . . . . . . . . . . . . . . . . . . . . 9-20 combustion . . . . . . . . . . . . . . . . . . . . 1-74
Loudspeaker . . . . . . . . . . . . . . . . . . . . . . 9-24 Nozzle
LPG holder . . . . . . . . . . . . . . . . . . . . . . . . 1-80
shut-off valve . . . . . . . . . . . . . . . . . . . . 9-8 needle . . . . . . . . . . . . . . . . . . . . . . . . 1-80
LPG cylinder Nozzles
pressure in the . . . . . . . . . . . . . . . . . . 1-30 defective nozzles . . . . . . . . . . . . . . . . 1-82
LPG installation Number plate light . . . . . . . . . . . . . . . . . . 9-16
function . . . . . . . . . . . . . . . . . . . . . . . 1-27
O
off position . . . . . . . . . . . . . . . . . . . . . 1-28
operating position . . . . . . . . . . . . . . . . 1-28 Oil pressure switch . . . . . . . . . . . . . . 9-4, 9-10
operation . . . . . . . . . . . . . . . . . . . . . . 1-28 One-way restrictor . . . . . . . . . . . . . . . . . . 1-83
shutdown . . . . . . . . . . . . . . . . . . . . . . 1-28 Overrun fuel cut-off . . . . . . . . . . . . . . . . . 1-68
start . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28
P
LTC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-2
adaptation . . . . . . . . . . . . . . . . . . . . . . 2-2 Parking brake cable
basic structure, overview . . . . . . . . . . . 0-4 adjustment . . . . . . . . . . . . . . . . . . . . . . 4-7
codes of composite instrument . . . . . . 0-14 Phase sensor
codes, traction control . . . . . . . . . . . . . 0-9 exhaust camshaft . . . . . . . . . . . . . . . . . 9-8
fault detection . . . . . . . . . . . . . . . . . . . 2-2 intake camshaft . . . . . . . . . . . . . . . . . . 9-8
lift control codes . . . . . . . . . . . . . . . . . 0-12 Piston
system overview . . . . . . . . . . . . . . . . . 0-8 projection . . . . . . . . . . . . . . . . . . . . . 1-111
Piston position check . . . . . . . . . . . . . . . 1-110
Position light . . . . . . . . . . . . . . . . . . . . . . 9-16

Service Training – 394 804 2401 EN – 01/2005 5

0 g
Index

Positioning magnet Roller

throttle valve . . . . . . . . . . . . . . . . . . . . 9-6 radial clearance . . . . . . . . . . . . . . . . . . 8-4
Pressure adjustment side clearance . . . . . . . . . . . . . . . . . . . 8-4
control valve . . . . . . . . . . . . . . . . . . . . 7-4 Roller clearance
Pressure sensor axial, outer mast . . . . . . . . . . . . . . . . . . 8-5
of intake air . . . . . . . . . . . . . . . . . . . . . 9-6 fork carriage . . . . . . . . . . . . . . . . . . . . . 8-4
Pressure switch lateral, middle, inner mast . . . . . . . . . . . 8-5
air conditioning . . . . . . . . . . . . . . . . . . 9-22 radial, outer, middle, inner mast . . . . . . 8-5
Pressure test points side . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4
overview . . . . . . . . . . . . . . . . . . . . . . 2-18 Rotating beacon . . . . . . . . . . . . . . . . . . . . 9-22
Pressure values Running direction
overview . . . . . . . . . . . . . . . . . . . . . . 2-19 ribbed V-belt . . . . . . . . . . . . . . . . . . . . 1-2
Pretension
solenoid . . . . . . . . . . . . . . . . . . . . . . . 1-37
S
Primary valve Safety concept
area valve . . . . . . . . . . . . . . . . . . . . . 1-30 engine control . . . . . . . . . . . . . . . . . 1-141
control . . . . . . . . . . . . . . . . . . . . . . . . 1-30 Sealing flange
Problem crankshaft . . . . . . . . . . . . . . . . . . . . 1-106
cause . . . . . . . . . . . . . . . . . . . . . . . 1-142 crankshaft, installation . . . . . . . . . . . 1-107
Protective diode crankshaft, remove . . . . . . . . . . . . . 1-107
shut-off valve . . . . . . . . . . . . . . . . . . . 1-33 Sealing ring
PTFE sealing ring . . . . . . . . . . . . . . . . . . 1-104 install the pulley . . . . . . . . . . . . . . . . 1-103
Pulley PTFE, characteristic . . . . . . . . . . . . . 1-104
freewheel . . . . . . . . . . . . . . . . 1-26, 1-138 remove pulley . . . . . . . . . . . . . . . . . 1-103
Seat heating . . . . . . . . . . . . . . . . . . . . . . 9-26
R Secondary diaphragm
Radial clearance opening pressure . . . . . . . . . . . . . . . . 1-30
roller . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4 Secondary membrane . . . . . . . . . . . . . . . 1-28
Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-24 Sensor
Ratchet actual speed . . . . . . . . . . . . . . . . . . . 1-63
chain tensioner . . . . . . . . . . . . . . . . . 1-14 control sleeve position . . . . . . . . . . . . 1-60
Readings coolant temperature . . . . . . . . . . . . . . 1-49
compression . . . . . . . . . . . . . . . . . . . . 1-3 engine rpm (BEQ) . . . . . . . . . . . . . . . 1-51
Regeneration fuel temperature . . . . . . . . . . . . . . . . . 1-53
warning light . . . . . . . . . . . . . . . . . . . 9-24 height sensor . . . . . . . . . . . . . . . . . . . 1-59
Relay needle stroke . . . . . . . . . . . . . . . . . . . 1-58
layout . . . . . . . . . . . . . . . . . . . . . . . . . 6-2 Sensor wheel . . . . . . . . . . . . . . . . . . . . . . 1-51
Release valve . . . . . . . . . . . . . . 2-2, 9-6, 9-12 Sequence valve
Residual quantity switch . . . . . . . . . . 9-4, 9-10 3rd gear pump . . . . . . . . . . . . . . 9-6, 9-12
Reversing signal . . . . . . . . . . . . . . . . . . . 9-22 Serial number
Ribbed V-belt mast . . . . . . . . . . . . . . . . . . . . . . . . . . 8-1
drive belt routing of BEQ engine . . . . 1-100 Service brake cable
engine VW BEQ . . . . . . . . . . . . . . . . . 1-99 adjustment. . . . . . . . . . . . . . . . . . . . . . 4-8
removal and installation . . . . . . . . . . . 1-99
VW BMF engine . . . . . . . . . . . . . . . . . 1-2

6 Service Training – 394 804 2401 EN – 01/2005

 g 0
Index

Shut-off valve Swivelling time

electromagnetic . . . . . . . . . . . . . . . . . 1-28 variable-displacement pump . . . . . . . . . 2-5
fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 9-14
LPG . . . . . . . . . . . . . . . . . . . . . . 1-33, 9-8
T
protective diode . . . . . . . . . . . . . . . . . 1-33 Tank level sensor . . . . . . . . . . . . . . . 9-4, 9-10
soot filter . . . . . . . . . . . . . . . . . . . . . . 9-24 Temperature
Side clearance fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 1-53
roller . . . . . . . . . . . . . . . . . . . . . . . . . . 8-4 Temperature sensor
Side marker light . . . . . . . . . . . . . . . . . . . 9-16 for hydraulic oil . . . . . . . . . . . . . . 9-6, 9-12
Slide pads Terminal DFM . . . . . . 1-26, 1-27, 1-138, 1-139
duplex mast, removal . . . . . . . . . . . . . . 8-8 Test
standard mast, removal . . . . . . . . . . . . 8-6 boost pressure . . . . . . . . . . . . . . . . . . 2-26
triplex mast, remove . . . . . . . . . . . . . . 8-10 high pressure of HPV 105 -02 . . . . . . . 2-27
Slide rail start of delivery of HPV 105 -02 . . . . . . 2-26
camshaft chain . . . . . . . . . . . . . . . . . . 1-13 wheel speed . . . . . . . . . . . . . . . . . . . 2-27
Solenoid Thread reach . . . . . . . . . . . . . . . . . . . . . . 8-21
pretension of throttle plate . . . . . . . . . 1-37 mechanical adjustment tilt cylinders . . 8-21
Soot filter . . . . . . . . . . . . . . . . . . . . . . . . . 9-24 Three-way catalytic converter . . . . . . . . . . 1-44
control unit . . . . . . . . . . . . . . . . . . . . 9-24 catalytic layer . . . . . . . . . . . . . . . . . . . 1-45
fan . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-24 monolith . . . . . . . . . . . . . . . . . . . . . . 1-45
flame sensor . . . . . . . . . . . . . . . . . . . 9-24 operating conditions . . . . . . . . . . . . . . 1-45
glow plug . . . . . . . . . . . . . . . . . . . . . . 9-24 rare metal . . . . . . . . . . . . . . . . . . . . . 1-45
metering pump . . . . . . . . . . . . . . . . . . 9-24 Throttle valve
shut-off valve . . . . . . . . . . . . . . . . . . . 9-24 positioning magnet . . . . . . . . . . . . . . . . 9-6
Speed sensor Tilt angle
actual speed sensor . . . . . . 1-63, 9-6, 9-12 adjustment . . . . . . . . . . . . . . . . . . . . . 8-17
Start inhibit marking reference points . . . . . . . . . . 8-17
brake pedal switch . . . . . . . . . . . 9-4, 9-10 sensor . . . . . . . . . . . . . . . . . . . . . . . . 8-17
Start of delivery . . . . . . . . . . . . . . . . . . . . 2-12 sensor calibration . . . . . . . . . . . . . . . . 8-18
of the variable-displacement pump . . . 2-11 tables . . . . . . . . . . . . . . . . . . . . . . . . 8-18
Starting quantity control . . . . . . . . . . . . . . 1-68 Tilt cylinder . . . . . . . . . . . . . . . . . . . . . . . 8-21
Steering system installation . . . . . . . . . . . . . . . . . . . . . 8-30
emergency steering . . . . . . . . . . . . . . . 4-3 mechanical adjustment . . . . . . . . . . . 8-21
functional description . . . . . . . . . . . . . . 4-1 removal . . . . . . . . . . . . . . . . . . . . . . . 8-28
steering . . . . . . . . . . . . . . . . . . . . . . . . 4-2 sealing . . . . . . . . . . . . . . . . . . . . . . . . 8-29
steering against the stop . . . . . . . . . . . . 4-3 Timing valve . . . . . . . . . . . . . . . . . . . . . . . 9-8
Strobe . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-22 Toothed belt . . . . . . . . . . . . . . . . . . . . . . 1-88
Stud change . . . . . . . . . . . . . . . . . . . . . . . 1-87
in cylinder head . . . . . . . . . . . . . . . . . 1-10 injection pump, adjustment . . . . . . . . . 1-97
Suction filter injection pump, overview . . . . . . . . . . 1-97
vacuum switch . . . . . . . . . . . . . . 9-4, 9-10 installation . . . . . . . . . . . . . . . . . . . . . 1-89
Swash angle . . . . . . . . . . . . . . . . . . . . . . 2-11 removal . . . . . . . . . . . . . . . . . . . . . . . 1-88
adjustment . . . . . . . . . . . . . . . . . . . . . 2-12 tightening . . . . . . . . . . . . . . . . . . . . . . 1-90
Switch-over valve . . . . . . . . . . . . . . . . . . . 2-15 Towing . . . . . . . . . . . . . . . . . . . . . . . . . . 2-13
remove . . . . . . . . . . . . . . . . . . . . . . . 2-16 Travel direction switch . . . . . . . . . . . 9-6, 9-12

Service Training – 394 804 2401 EN – 01/2005 7

0 g
Index

Travel drive Vaporiser

braking . . . . . . . . . . . . . . . . . . . . . . . . 2-5 heated . . . . . . . . . . . . . . . . . . . . . . . . 1-30
check . . . . . . . . . . . . . . . . . . . . . . . . . 2-20 off position . . . . . . . . . . . . . . . . . . . . . 1-30
driving . . . . . . . . . . . . . . . . . . . . . . . . . 2-4 operating position . . . . . . . . . . . . . . . . 1-30
governing of truck speed . . . . . . . . . . . 2-4 secondary membrane . . . . . . . . . . . . 1-28
moving off on a slope . . . . . . . . . . . . . . 2-4 Vibration damper
power control . . . . . . . . . . . . . . . . . . . . 2-4 lock . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14
reversal of direction of travel . . . . . . . . . 2-5
Truck data
W
management . . . . . . . . . . . . . . . . . . . 9-20 Warning light,
Truck speed regeneration . . . . . . . . . . . . . . . . . . . 9-24
control . . . . . . . . . . . . . . . . . . . . . . . . 2-4 Washing system pump . . . . . . . . . . . . . . . 9-26
Turbocharger . . . . . . . . . . . . . . . . . . . . . 1-130 Water pump . . . . . . . . . . . . . . . . . . . . . . 1-134
Turn signal indicator check . . . . . . . . . . . . . . . . . . . . . . . . 1-135
higher . . . . . . . . . . . . . . . . . . . . . . . . 9-18 continued circulation . . . . . . . . . . . . . 1-22
Turn signal light . . . . . . . . . . . . . . . . . . . . 9-16 installation . . . . . . . . . . . . . . . . . . . . 1-135
Turn signal system . . . . . . . . . . . . . . . . . . 9-16 removal . . . . . . . . . . . . . . . . . . . . . . 1-134
Wear limit
V compression . . . . . . . . . . . . . . . . . . . . 1-3
Vacuum Windscreen wiper . . . . . . . . . . . . . . . . . . 9-26
restricted air filter . . . . . . . . . . . . . . . . 1-30 motor . . . . . . . . . . . . . . . . . . . . . . . . . 9-26
Vacuum pump . . . . . . . . . . . . . . . . . . . . 1-122 Working hydraulics
drive . . . . . . . . . . . . . . . . . . . . . . . . . 1-47 speed control . . . . . . . . . . . . . . . . . . . . 2-4
Vacuum switch Working lights . . . . . . . . . . . . . . . . . . . . . 9-16
suction filter . . . . . . . . . . . . . . . . 9-4, 9-10 positions . . . . . . . . . . . . . . . . . . . . . . . 6-8
Valve
for injection start . . . . . . . . . . . . . . . . . 9-14
Z
Valve stem Zero position
seal dismantle . . . . . . . . . . . . . . . . . 1-115 hydraulic, adjustment . . . . . . . . . . . . . 2-12
seal install . . . . . . . . . . . . . . . . . . . . 1-115
Valve timing
adjustment . . . . . . . . . . . . . . . . . . . . . 1-13
check . . . . . . . . . . . . . . . . . . . . . . . . . 1-11

8 Service Training – 394 804 2401 EN – 01/2005

Linde AG
Geschäftsbereich Linde Material Handling

Linde AG
Linde Material Handling Division

394 804 2401 EN – 01/2005

Service Training

Linde IC Engined Truck

H40D H40T H45D H45T H50-500T
H50-500D

Series 394

Edition 01/2005
Annex

This service document is provided for use only and remains the exclusive property of Linde AG,
Linde Material Handling Division.

Service Training – 394 804 2401 EN – 01/2005

9 Circuit diagrams
Hydraulic circuit diagrams

Hydraulic wiring diagram

9-1 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

A Auxiliary hydraulic system for duplex or triplex mast C Linde Truck Control 33 Control piston A = forward, B = reverse 51 Pump to release brake
1 Hose reel, left 19 Central control lever for working hydraulics 34 Check valve 52 Check valve
2 Hose reel, right 20 Central control lever for auxiliary hydraulics 3 and 2 35 Sensor 53 Relief valve
36 4/2-port directional control valve 54 2/2-port directional control valve
B Working hydraulics D Gear-type pump
37 Pilot valve
3 Tilt cylinder 21 Solenoid valve (aux. brake) M Fan drive
38 Combined feed/pressure relief valve p = 425+20 bar
4 Standard mast 22 Restrictor valve 55 Solenoid valve
39 Boost pressure valve p = 21+0.5 bar
5 Port for auxiliary hydraulics 4, standard mast 23 3/3 port directional control valve (priority valve) 56 Hydraulic motor
40 Brake valve
6 Port for auxiliary hydraulics 3, standard mast 24 2/2-port directional control valve
41 Auxiliary control valve N Cooler
7 Solenoid valve 25 Gear pump, q = 9 cm3/rev
42 Bypass valve (towing device)
8 Tilt brake valve 26 Gear pump, q = 18 cm3/rev O Pressure filter (boost pressure)
43 Purge valve p = 15 bar
9 Load holding valve 27 Gear pump, q = 16 cm3/rev
44 Shuttle valve P Drive unit
10 Check valve
E Working hydraulics pressure filter 45 Servopiston, Y = forward, Z = reverse 57 Multiple disc brake
11 Pressure relief valve 1: on H 40 p = 250+5 bar, on H
46 2/2-port directional control valve 58 Fixed-displacement hydraulic motor HMF 135 -02 with
45/50-500 p = 275+5 bar F Steering control valve 47 Proportional valve transmission GR6H -02
12 2/2-port directional control valve (pressure balance) 28 Make-up valve 48 Release valve
13 Release valve 29 Secondary valve p = 220+10 bar R Oil reservoir
14 Directional control valve for lifting/lowering 30 Steering control valve I Internal combustion engine 59 Breather filter with suction filter and pressurising valve, p
15 Directional control valve for tilting 31 Primary valve, p = 120 +5 bar = 0.35 ±0.15 bar
K Speed actuator of injection pump
16 Pressure relief valve 2: p = 170+10 bar 60 Suction filter with bypass valve p = 0.25 bar
17 Directional control valve for auxiliary hydraulics 3 G Steering cylinder
L Brake release valve
18 Directional control valve for auxiliary hydraulics 4 Variable-displacement hydraulic pump 49 Bypass valve
32 Variable-displacement pump HPV 105 -02 50 3/2-port directional control valve

Service Training – 394 804 2401 EN – 01/2005 9-2

9 Circuit diagrams
Electrical circuit diagrams

Circuit Diagram Standard Equipment, LPG Engine, Sheet 1

9-3 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

B1 Tank level sensor (40-250 ), vol. filling, 33 6P1 Composite instrument, 25-40 6X1 Connector 10 pins (6P1), 26-39 Code Colour primary
F2 Fuse, 4 S1 Ignition switch, 9-16 6X2 Connector 7 pins (diagnosis), 48
RD red
F5 Fuse, 26 S2 Brake pedal switch 2 (start inhibit), 12-14
F6 Fuse, 28 S3 Suction filter vacuum switch, 31 Code Colour primary VT violet
F7 Fuse, 73 S6 Residual quantity switch (pressure switch), 33 BK black WH white
F13 Fuse, 61 0S1 Oil pressure switch, 28
F14 Fuse, 64 4S1 Horn button, 73 BN brown YE yellow
F15 Fuse, 67 X1 Connector 10 pins (S1), 9-15, 73 BU blue
G1 Three-phase alternator with regulator, 1-5 X2 Connector 3 pins (S2), 13, 14 The number before the line colour corresponds to the line
GN green cross-section.
G2 Battery, 7 X6 Connector 2 pins (S6), 33
4H1 Horn, 73 X10 Connector 18 pins (central electr. system), 21, 64-69 GY grey
Lines without cross-section information: F = 0.75 mm2
K2 Starting relay, 10-13 X1 Connector 9 pins (control centre), 23, 65-67 OG orange
M1 Starter, 9-11 X15 Connector 2 pins (CAN), 41

Service Training – 394 804 2401 EN – 01/2005 9-4

9 Circuit diagrams
Electrical circuit diagrams

Circuit Diagram Standard Equipment, LPG Engine, Sheet 2

9-5 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1B1 Actual speed sensor, 85-86 2X4 Connector 6 pins (2B2), 128-133 Code Colour primary Earth sensors
1B2 Electronic truck speed controller - double potentiometer, 2X5 Connector 10 pins (valve block), 137-157
BN brown :88 :61
85-90 1Y1 Retarder, 99
1B4 Temperature sensor for hydraulic oil, 85 1Y2 Solenoid valve Y forward, 102 BU blue :89 :80
1B8 Pressure sensor of intake air, 90-92 1Y3 Solenoid valve Z reverse, 105 GN green :96 :81
2B1 Joystick for basic functions, 120-125 1Y4 Release valve, 108
2B2 Joystick for auxiliary functions, 127-133 1Y5 Valve - fan, 97 GY grey
orange Encoding
2B3 Double potentiometer for mast tilt angle, 138-143 1Y7 Throttle valve positioning magnet, 96 OG
F8 Fuse, 81 1Y10 Sequence valve 3rd gear pump, 95 H 40 H 45/H 50
RD red
F9 Fuse, 83 2Y1 Valve - lowering, 135 :10 X X
N1 Electronic truck speed control LHC, 81-158 2Y2 Valve - lifting, 137 VT violet
S4 Seat switch, 149-150 2Y3 Valve - forward tilting, 140 :28 X
WH white
1S1 Brake pedal switch 1, 112-113 2Y4 Valve - backward tilting, 132 :47 X
YE yellow
1S2 Travel direction switch - single-pedal model, 117-123 2Y5 Valve - option 1B, 146
:52 X
X4 Connector 3 pins (seat switch), 149-150 2Y6 Valve - option 1A, 148
X10 Connector 18 pins (control centre), 100-112 2Y7 Valve - option 2B, 151 5V sensors
X1 Connector 9 pins (control centre), 113-116 2Y8 Valve - option 2A, 153
The number before the line colour corresponds to the line
Lift Drive cross-section.
1X1 Connector 3 pins (1B1), 84 2Y9 Release valve, 157
1X2 Connector 3 pins (1S1), 112, 113 :115 :1
Lines without cross-section information: F = 0.75 mm2
1X3 Connector 6 pins (single-pedal model), 118-122 Code Colour primary :116 :2
2X1 Connector 2 pins (micro-filter), 135, 136 BK black :118 :3 Retarder only with H 45 / H 50
2X3 Connector 6 pins (2B1), 120-125

Service Training – 394 804 2401 EN – 01/2005 9-6

9 Circuit diagrams
Electrical circuit diagrams

Circuit Diagram Standard Equipment LPG Engine, Sheet 3

9-7 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

0B1 Coolant temperature sensor, 189-192 0K4 Coolant return-flow pump relay, 233-236 1Y6 LPG shut-off valve, 182 Code Colour primary
0B2 Engine speed sensor, 163-165 0M1 Coolant return-flow pump, 236 orange
(1) Mass point engine block. OG
0B6 Intake air pressure and temperature sensor, 167-170 0N1 LPG installation controller, 163 -234
0B10 Phase sensor intake camshaft, 172-175 0T1 Ignition coil cylinder 1, 199-202 RD red
*2) Line only with uncontrolled catalytic converter
0B11 Lambda probe, 184-188 0T2 Ignition coil cylinder 2, 204-207 VT violet
0B13 Phase sensor exhaust camshaft, 178-181 0T3 Ignition coil cylinder 3, 209-212 *3) 0B11, 0X12 and 0Y3, 0X11 only with controlled cata-
0E1 Glow plug cylinder 1, 201 0T4 Ignition coil cylinder 4, 214-217 WH white
lytic converter
0E2 Glow plug cylinder 2, 206 0T5 Ignition coil cylinder 5, 219-222 YE yellow
0E3 Glow plug cylinder 3, 211 0T6 Ignition coil cylinder 6, 224-227 Firing order: Cylinder 1 - 5 - 3 - 6 - 2 - 4
0E4 Glow plug cylinder 4, 216 X10 Connector 18 pins (central electr. system), 175 The number before the line colour corresponds to the line
0E5 Glow plug cylinder 5, 221 0X7 Connector 3 pins (engine speed), 163-165 Code Colour primary
cross-section.
0E6 Glow plug cylinder 6, 226 0X11 Connector 2 pins (timing valve), 194 BK black
F10 Fuse, 161 0X12 Connector 4 pins (Lambda probe), 187, 186 Lines without cross-section information: F = 0.75 mm2
BN brown
F11 Fuse, 178 0X13 Connector 2 pins (camshaft), 197
F12 Fuse, 171 0X14 Connector 2 pins (camshaft), 200 BU blue
F16 Fuse, 236 0Y3 Timing valve, 194 GN green
0H1 Fault light, 175 0Y7 Valve camshaft adjustment intake, 197
0K3 Supply relay, 161-164 0Y8 Valve camshaft adjustment exhaust, 200 GY grey

Service Training – 394 804 2401 EN – 01/2005 9-8

9 Circuit diagrams
Electrical circuit diagrams

Circuit Diagram Standard Equipment Diesel Engine, Sheet 1

9-9 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

B1 Tank level sensor, 33 6P1 Composite instrument, 25-40 6X2 Connector 4 pins (diagnosis), 47 Code Colour primary
F2 Fuse, 4 S1 Ignition switch, 9-16
Colour primary VT violet
F5 Fuse, 26 S2 Brake pedal switch 2 (start inhibit), 12-14 Code
F6 Fuse, 28 S3 Suction filter vacuum switch, 31 BK black WH white
F7 Fuse, 73 S6 Residual quantity switch (pressure switch), 33 YE yellow
F13 Fuse, 61 0S1 Oil pressure switch, 28 BN brown
F14 Fuse, 64 4S1 Horn button, 73 BU blue The number before the line colour corresponds to the line
F15 Fuse, 67 X1 Connector 6 pins (S1), 9-15, 73 cross-section.
GN green
G1 Three-phase alternator with regulator, 1-5 X2 Connector 3 pins (S2), 13, 14
G2 Battery, 7 X10 Connector 18 pins (central electr. system), 21, 64-69 GY grey Lines without cross-section information: F = 0.75 mm2
4H1 Horn, 73 X1 Connector 9 pins (control centre), 12-67 OG orange
K2 Starting relay, 11-13 X15 Connector 2 pins (CAN), 41
M1 Starter, 9-11 6X1 Connector 10 pins (6P1), 26-39 RD red

Service Training – 394 804 2401 EN – 01/2005 9-10

9 Circuit diagrams
Electrical circuit diagrams

Circuit Diagram Standard Equipment Diesel Engine, Sh. 2

9-11 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1B1 Actual speed sensor, 85-86 2X5 Connector 10 pins (valve block), 133-153 Code Colour primary Earth sensors
1B2 Electronic truck speed controller - double potentiometer, 1Y1 Retarder, 99
BU blue :88 :61
85-90 1Y2 Solenoid valve Y forward, 91
1B4 Temperature sensor for hydraulic oil, 88 1Y3 Solenoid valve Z reverse, 94 GN green :89 :80
2B1 Joystick for basic functions, 116-121 1Y4 Release valve, 96 GY grey :96 :81
2B2 Joystick for auxiliary functions, 123-129 1Y5 Valve - fan, 92
2B3 Double potentiometer for mast vertical position, 137-142 1Y10 Sequence valve 3rd gear pump, 95 OG orange
Encoding
F8 Fuse, 81 1Y11 Cold start valve, 101 RD red
F9 Fuse, 83 2Y1 Valve - lowering, 131 H 40 H 45/H 50
VT violet
N1 Electronic truck speed control LHC, 81-158 2Y2 Valve - lifting, 133 :10 X X
S4 Seat switch, 149-150 2Y3 Valve - forward tilting, 136 WH white
1S1 Brake pedal switch, 106-107 2Y4 Valve - backward tilting, 138 yellow :28 X
YE
1S2 Travel direction switch - single-pedal model, 113-119 2Y5 Valve - option 1B, 142 :47 X
X4 Connector 3 pins (seat switch), 149-150 2Y6 Valve - option 1A, 144
5V sensors :52 X
X10 Connector 18 pins (control centre), 98-108 2Y7 Valve - option 2B, 148
X1 Connector 9 pins (control centre), 110-111 2Y8 Valve - option 2A, 150 Lift Drive
1X1 Connector 3 pins (1B1), 84 2Y9 Release valve, 153
The number before the line colour corresponds to the line
:115 :1 cross-section.
1X2 Connector 3 pins (1S1), 106-107
1X3 Connector 6 pins (EP), 115-119 Code Colour primary :116 :2
Lines without cross-section information: F = 0.75 mm2
2X1 Connector 2 pins (micro-filter), 134-135 BK black :118 :3
2X3 Connector 6 pins (2B1), 116-121
2X4 Connector 6 pins (2B2), 124-129 BN brown

Service Training – 394 804 2401 EN – 01/2005 9-12

9 Circuit diagrams
Electrical circuit diagrams

Circuit Diagram Standard Equipment Diesel Engine, Sheet 3

9-13 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

0B1 Coolant temperature sensor, 187-190 0K2 Relay terminal 30 for VW control unit, 170-173 Code Colour primary Code Colour primary
0B2 Engine speed sensor, 194-197 0N1 Control unit for direct diesel injection system, 171-236
BK black VT violet
0B3 Sensor for fuel temperature/control collar, 206-214 0N2 Electronic immobiliser, 184-188
0B4 Sensor for inlet pipe pressure/inlet pipe temperature, 0R1 Glow plugs, 161-166 BN brown WH white
178-181 0X1 Connector 10 pins, 205-220 BU blue YE yellow
0B5 Needle lift sensor, 200-202 0X2 Connector 2 pins, 200-202
0B6 Air flow sensor, 173-175 0X3 Connector 3 pins, 194 -197 GN green
The number before the line colour corresponds to the line
F1 Fuse, 161 0Y1 Fuel shut-off valve, 218 GY grey cross-section.
F11 Fuse, 170 0Y2 Valve for injection start, 220 orange
OG
F12 Fuse, 175 0Y4 Valve for boost pressure limitation, 222 Lines without cross-section information: F = 0.75 mm2
0K1 Glow plug relay, 161-163 RD red

Service Training – 394 804 2401 EN – 01/2005 9-14

9 Circuit diagrams
Electrical circuit diagrams

Wiring diagram for optional lighting

9-15 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1 Working lights, items 1 and 2 5E24 Position light, right, 50 5K2 Relay, brake light, 72-74 Code Colour primary
2 Working lights, items 1 and 2, lighting higher F3 Fuse MTA 70 A (terminal 5), 3 5K4 Relay, working light item 8
BK black
3 Working lights, items 3 and 4 F14 Fuse 2 A (terminal 58), 1 5S1 Working light switch items 1 and 2, 9-11
4 Working lights, items 7 and 8 5F1 Fuse 15 A (working lights items 1 and 2), 9 5S2 Working light switch items 3 and 4, 15-23 BN brown
5 Lighting 5F2 Fuse 15 A (working lights items 3 and 4), 15, 21 5S3 Working light switch item 8, 27-35 BU blue
6 Turn signal and hazard warning flasher 5F4 Fuse 7.5 A (working light item 8), 30 5S11 Light switch, 39-45
7 Brake light 5F5 Fuse 15 A (lighting terminal 15), 60 5S12 Hazard warning light switch, 60-66 GN green
5E1 Working light, front left, bottom (item 1), 7, 13 5F6 Fuse 10 A (lighting terminal 30) 5S13 Turn signal switch, 62-64 GY grey
5E2 Working light, front right, bottom (item 2), 9, 15 5F7 Fuse 5 A (brake light), 74 X10 Connector 18 pins (to standard equipment), 1, 32, 72 orange
OG
5E3 Working light, front left, top (item 3), 19 5F8 Fuse 7.5 A (headlight, left), 39 5X4 Connector 12 pins (overhead guard lighting), 13, 15,
5E4 Working light, front right, bottom (item 4), 21 5F9 Fuse 7.5 A (headlight, right), 41 39-74 RD red
5E7 Working light, rear right, top (item 8), 29 5F10 Fuse 5 A (position light, left), 43 5X4 Connector 6 pins (lighting, rear), 47-74 VT violet
5E9 Number plate light, left, 55 5F11 Fuse 5 A (position light, right), 48 5X4 Connector 12 pins (working lights items 1 and 2), 7, 9
5E10 Number plate light, right, 57 5H1 Turn signal light, front left, 61 5X5 Connector 2 pins (working lights items 3 and 4), 15, 21 WH white
5E11 Dip beam, left, 39 5H2 Turn signal light, front right, 64 5X6 Connector 2 pins (working lights item 8), 29 YE yellow
5E12 Dip beam, right, 41 5H3 Turn signal light, rear left, 60 5X7 Connector 6 pins (headlight, left), 39, 43, 61
5E13 Side marker light, front left, 43 5H4 Turn signal light, rear right, 66 5X8 Connector 6 pins (headlight, right), 41, 48, 64 The figure before the cable colour corresponds to the
5E14 Side marker light, front right, 48 5H10 Turn signal indicator light, 69 5X10 Connector 2 pins (number plate light), 55 gauge.
5E15 Side marker light, rear left, 47 5H20 Brake light, right, 74 5X16 Connector 2 pins (number plate light), 55
5E16 Side marker light, rear right, 52 5H21 Brake light, left, 76 5X18 Connector 2 pins (position light, right), 50 Cables without information on the gauge: F = 0.75 mm2
5E19 Working light, rear left, top (item 7), 31 K1 Auxiliary relay terminal 58, 1-3 5X19 Connector 2 pins (position light, left), 45
5E23 Position light, left, 45 5K1 Flasher, 64-67

Service Training – 394 804 2401 EN – 01/2005 9-16

9 Circuit diagrams
Electrical circuit diagrams

Wiring diagram for options, lighting higher

9-17 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1 Lighting higher 5F8 Fuse (headlight, left), 403 5X1 Connector 12 pins (overhead guard lighting), 412, 420, Code Colour primary
2 Turn signal indicator and hazard warning flasher higher 5F9 Fuse (headlight, right), 405 425-436
BU blue
3 Brake light higher 5F10 Fuse (position light, left), 407 5X7 Connector 6 pins (headlight, left), 403, 407, 426
4 Reversing light higher 5F11 Fuse (position light, right), 415 5X8 Connector 6 pins (headlight, right), 405, 415, 429 GN green
5 12V socket 9F10 Fuse (12V socket), 455 5X11 Connector 12 pins (lighting higher), 403-446 GY grey
5E11 Dip beam, left, 403 5H1 Turn signal light, front left, 426 5X12 Connector 5 pins (side marker light, rear right), 417, 432,
5E12 Dip beam, right, 405 5H2 Turn signal light, front right, 429 441, 448 OG orange
5E13 Side marker light, front left, 407 5H3 Turn signal light, rear left, 424 5X13 Connector 5 pins (side marker light, rear left), 409, 424, RD red
5E14 Side marker light, front right, 415 5H4 Turn signal light, rear right, 432 443, 4465X18
VT violet
5E15 Side marker light, rear left, 409 5H10 Turn signal indicator light, 436 5X18 Connector 2 pins (position light, right), 420
5E16 Side marker light, rear right, 417 5H20 Brake light, right, 441 5X19 Connector 2 pins (position light, left), 412 WH white
5E17 Reversing light, left, 446 5H21 Brake light, left, 443 9X15 Connector 3 pins (12V socket), 455 YE yellow
5E18 Reversing light, right, 448 5K1 Flasher, 430-432 9X16 Connector 2 pins (12V socket), 455
5E23 Position light, left, 412 5K2 Relay, brake light, 439-441 The figure before the cable colour corresponds to the
5E24 Position light, right, 420 5S11 Light switch, 402-408 Code Colour primary
gauge.
5F5 Fuse (lighting terminal 15), 424 5S12 Hazard warning light switch, 424-432 BK black
5F6 Fuse (lighting terminal 30), 428 5S13 Turn signal switch, 427-429 Cables without information on the gauge: F = 0.75 mm2
5F7 Fuse (brake light), 441 X10 Connector 18 pins (to standard equipment), 439 BN brown

Service Training – 394 804 2401 EN – 01/2005 9-18

9 Circuit diagrams
Electrical circuit diagrams

Wiring diagram for optional equipment, truck data management

9-19 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1 Truck data management X1 Connector 10 pins (interface main cable loom to end cable Code Colour primary Code Colour primary
6A1 Truck data management unit, 488-502 loom), 484
BU blue WH white
6A2 GPRS unit, 505-510 6X4 Connector 14 pins (truck data management), 488-502
6B2 Load sensor, 512-516 6X5 Connector 3 pins (truck data management unit interface), GN green YE yellow
F15 Fuse, 499 497, 498 GY grey
6F1 Fuse, 497 6X7 Connector 5 pins (data transfer), 495-499 The figure before the cable colour corresponds to the
K2 Starter relay, 482-485 6X9 Connector 4 pins (GPRS unit), 505-508 OG orange gauge.
6W1 GPRS antenna, 510 RD red
X10 Connector 18 pins (to standard equipment), 499 Code Colour primary Cables without information on the gauge: F = 0.75 mm2
VT violet
X11 Connector 9 pins (to standard equipment, 501 BK black
X15 Connector 2 pins (CAN connection), 489, 495
BN brown

Service Training – 394 804 2401 EN – 01/2005 9-20

9 Circuit diagrams
Electrical circuit diagrams

Wiring diagram for optional heater

9-21 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1 Heater 4K1 Reversing signal relay, 210-214 9X10 Connector 1 pin (air conditioning), 182 Code Colour primary
2 Heater with air conditioning 9M7 Fan motor 1 air conditioning, 188 9X11 Connector 6 pins (air conditioning), 178-194
VT violet
3 Strobe and rotating beacon via terminal 58 9M8 Fan motor 2 air conditioning, 191 9X12 Connector 2 pins (heater), 164, 170, 172
4 Strobe and rotating beacon via switch 9M9 Fan motor 3 air conditioning, 194 9X13 Connector 4 pins (air conditioning pressure switch), WH white
5 Reversing signal continuous and switchable: off and on 4S3 Strobe and rotating beacon switch, 204-206, 212-217 178-180 YE yellow
when reversing 5S4 Switch for interior lighting, 232-235 9Y1 Electromagnetic coupling for air conditioning, 174
6 Interior lighting 9S6 Pressure switch, air conditioning, 177-179 The figure before the cable colour corresponds to the
4B1 Buzzer, 222 9V1 Free-wheel diode (electric coupling), 172 Code Colour primary
gauge.
5E8 Cabin lighting, 233 X10 Connector 18 pins (to standard equipment), 210 BK black
9E1 Heater, 161-167 X11 Connector 9 pins (to standard equipment), 182-184 Cables without information on the gauge: F = 0.75 mm2
9E2 Heater with air conditioning, 170-194 4X1 Connector 2 pins (strobe and rotating beacon, 226 BN brown
F4 Fuse 30 A (air conditioning), 182 4X2 Connector 6 pins (buzzer), 216-223 BU blue
4F1 Fuse 10 A (reversing signal), 214 4X3 Connector 2 pins (strobe and rotating beacon), 199
GN green
4F3 Fuse 7.5 A (strobe and rotating beacon), 199, 204 4X4 Connector 2 pins (strobe and rotating beacon), 204, 214
5F12 Fuse 5 A (interior lighting), 233 4X5 Connector 2 pins (buzzer), 221 GY grey
9F9 Fuse 20 A (heater), 164, 172 5X11 Connector 12 pins (lighting higher), 229 OG orange
4H4 Strobe, 199, 204, 214, 226 9X9 Connector 2 pins (heater and air conditioning), 164, 170,
4H5 Rotating beacon, 199, 204, 214, 226 172 RD red

Service Training – 394 804 2401 EN – 01/2005 9-22

9 Circuit diagrams
Electrical circuit diagrams

Wiring diagram for optional soot filter

9-23 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1 Soot filter 7H2 Prewarning and warning light (orange), 342 7X1 Connector 9 pins (interface to central electr. system), Code Colour primary
2 Radio 7H3 Fault light (red), 345 340-359 green
GN
7A1 Soot filter control unit , 327-374 K2 Starter relay, 323-325 7X2 Connector 4 pins (blower shut-off valve), 332, 335
7B1 Buzzer, 348 7K1 Glow plug current regulator, 374-376 7X3 Connector 2 pins (flame sensor), 366-367 GY grey
7B2 Flame sensor, 367 7K2 Auxiliary starter relay, 325-328 7X4 Connector 2 pins (glow plug), 376 OG orange
9E3 Radio, 389-397 7M1 Fan, 332 7X5 Connector 2 pins (metering pump), 339
9E4 Loudspeaker, left, 389 7M2 Metering pump, 339 9X2 Connector 3 pins (radio), 390-397 RD red
9E5 Loudspeaker, right, 394 7R1 Glow plug, 376 X Connector 3 pins (radio), 390-397 VT violet
F15 Fuse, 357 7S1 Starter switch, 352-353 7Y1 Shut-off valve, 335
WH white
7F1 Fuse (soot filter), 343 7S2 Emergency isolator switch, 357-359
7F2 Fuse (soot filter), 349 7V1 Decoupling diode, 336 Code Colour primary YE yellow
7F3 Fuse (glow plug), 376 9W1 Antenna, 395-396 BK black
9F7 Fuse (radio terminal 30), 390 X10 Connector 18 pins (to main cable loom), 340, 357 The figure before the cable colour corresponds to the
9F8 Fuse (radio terminal 15), 393 X11 Connector 9 pins (to main cable loom), 325, 364 BN brown gauge.
7H1 Warning light regeneration, 353 6X8 Connector 4 pins (diagnosis), 383 BU blue
Cables without information on the gauge: F = 0.75 mm2

Service Training – 394 804 2401 EN – 01/2005 9-24

9 Circuit diagrams
Electrical circuit diagrams

Circuit diagram for optional wipers

9-25 Service Training – 394 804 2401 EN – 01/2005

 Circuit diagrams 9
Electrical circuit diagrams

1 Windscreen wiper 9M1 Wiper motor, front, 91-95 9X7 Connector 3 pins (seat heating), 144, 152 Code Colour primary
2 Windscreen wiper, front 9M2 Wiper motor, rear, 110-113 9X14 Connector 2 pins (seat heating), 144, 152
VT violet
3 Windscreen wiper, rear 9M3 Wiper motor, roof, 130-134
4 Windscreen wiper, roof 9M4 Washing system pump, front, 98 Code Colour primary WH white
5 Seat with seat heating 9M5 Washing system pump, rear, 116 BK black YE yellow
6 Seat with seat heating and air cushioning 9M6 Washing system pump, roof, 137
9F1 Fuse 2 A (windscreen wipers, general), 83 9M10Compressor motor for unillusioned seat, 153 BN brown
The figure before the cable colour corresponds to the
9F2 Fuse 10 A (windscreen wiper, front), 96 9R2 Seat heating, 144, 151 BU blue gauge.
9F3 Fuse 7.5 A (windscreen wiper, rear and roof), 114 9S1 Switch for windscreen wiper, 82-87
GN green
9F4 Fuse 10 A (washing system pumps), 86 9S2 Switch for windscreen wiper, front, 82-89 Cables without information on the gauge: F = 0.75 mm2
9F6 Fuse 20 A (seat heating), 144, 152 9S3 Switch for windscreen wiper, rear, 101-109 GY grey
9K1 Windscreen wiper relay, front, 85-93 9S4 Switch for windscreen wiper, roof, 121-128 OG orange
9K2 Windscreen wiper relay, rear, 106-111 9X1 Connector 9 pins (windscreen wiper), 83-94
93 Windscreen wiper relay, roof, 125-132 9X5 Connector 6 pins (washing system pumps), 98, 116, 137 RD red

Service Training – 394 804 2401 EN – 01/2005 9-26

Linde AG
Geschäftsbereich Linde Material Handling

Linde AG
Linde Material Handling Division

394 804 2401 EN – 01/2005