Volkswagen 2004 Golf Manual

The Golf 2004
Electrical system
Design and function
Self-study programme 319
Service Training

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NEW Important
Note
This self-study programme shows the design and
function of new developments!
The contents will not be updated.
For the latest testing, setting and repair
instructions, please refer to the relevant
workshop literature.
S319_063
The most striking change compared with the previous model is the rear lighting of the Golf 2004.
The one-piece light unit, common on the previous model, has now been replaced by a two-piece light
unit. This is comprised of a separate independent light element in the side part and a fixed element in the
tailgate.
In this way, the car's relationship to the prestige Volkswagen models is made evident.
A bright and high quality appearance is achieved by day and by night by means of round elements,
comprised of several parts, located behind clear lenses.

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Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
LIN data bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Onboard power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Tyre pressure monitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Convenience and safety electronics. . . . . . . . . . . . . . . . . . 42
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Test yourself . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56

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Introduction
Fitting locations
The onboard electrical system of the Golf 2004 is
similar to that of the Touran. Golf 2004 and
Touran veh icles are based on the same platform.
The onboard electrical system of the Golf 2004 is
of the decentral design. Distribution of the fuse
boxes and relay sockets in various locations
facilitates quick and precise fault diagnosis.
Fuse boxes and relay slots in vehicle electrical system
Electrics box, on left in engine
compartment
Pre-fuse box, on left in
engine compartment

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Fuse box, on left in
dash panel
S319_001
Relay carrier of onboard power
supply control unit on left
under dash panel
Relay carrier, on left beneath
dash panel, above onboard
power supply control unit