Volkswagen Golf / Golf GTI / Golf Variant. Manual - part 770

Note

ABS malfunctions do not affect the brake system and the booster.

Conventional brake system stays operative even without ABS. A

change in braking behavior should be checked. When the ABS

indicator lamp is lit up, the rear wheels may lock prematurely dur‐

ing braking!

Configuration
1 - ABS Hydraulic Unit - N55- and ABS Control Module - J104-
2 - Brake Booster
The ABS Hydraulic Unit - N55- and ABS Control Module - J104-

are one unit. Separation can only be performed when removed

from vehicle. The hydraulic pump may also not be separated from

the ABS Hydraulic Unit - N55- .
Anti-Lock Braking System (ABS) Repair Information
♦ Before carrying out repair work on the ABS, determine the

cause of damage as well as the control module code using

“Guided Fault Finding”.

“Guided Fault Finding” is performed. Refer to Vehicle Diagnostic

Tester .
♦ Disconnect the battery ground cable when the ignition is

switched off.

♦ Before welding with an electric welding tool, observe the in‐

formation found here ⇒ General Information; Body Repairs,

Body Collision Repair .

♦ When handling brake fluid, observe the relevant safety pre‐

cautions and notes.

♦ After finishing any work that required opening the brake sys‐

tem, bleed the brake system using the Brake Charger/Bleeder

Unit - VAS5234- .

♦ During the final road test, make sure a controlled braking ma‐

neuver is performed at least one time (pulsing must be felt in

brake pedal).

♦ It is necessary to maintain a high level of cleanliness when

working on the ABS system.

♦ Do not use fluid containing mineral oils, for example oils,

grease, etc.

♦ Thoroughly clean all connection points and their surrounding

areas before loosening. However, do not use aggressive

cleaning agents such as brake cleaner, gasoline, thinners or

similar compounds.

♦ Place the removed parts on a clean surface and cover them.
♦ Carefully cover or seal opened components if the repair is not

performed immediately. (Use plugs from repair set 1 H0 698

311 A)

♦ Only use lint-free cloths.
♦ Remove the replacement parts from their packaging just prior

to installing them.

♦ Only use parts in their original packaging.
♦ Do not work with compressed air when the system is open.
♦ Do not move the vehicle.

♦ The valve coils in the ABS Control Module - J104- cannot be

readjusted.

♦ The valve coils in the ABS Control Module - J104- cannot be

replaced.

♦ The pressure sensor must not be changed or damaged.
♦ The pressure sensor cannot be replaced.
♦ The sensor housing must not be under any mechanical load.
♦ No measurements can be taken at the contacts inside the ABS

Control Module - J104- .

♦ No measurements can be taken at the contacts inside the ABS

Hydraulic Unit - N55- .

♦ The valve bodies inside the ABS Hydraulic Unit - N55- must

not be damaged or bent.

♦ The contacts cannot be replaced.
♦ Using contact sprays on the contacts and pressure sensor are

not permitted.

♦ No foreign objects may be between the ABS Control Module

- J104- and the ABS Hydraulic Unit - N55- .

♦ The ABS Control Module - J104- may be briefly exposed to a

maximum temperature of 95 °C (203 °F) when painting.

♦ The ABS Control Module - J104- may be exposed to a tem‐

perature of 85 °C (185 °F) for approximately two hours.

♦ Make sure that brake fluid cannot get into the connectors.

2

Component Location Overview

⇒ “2.1 Component Location Overview - ABS/ESP”, page 13

2.1

Component Location Overview - ABS/ESP

1 - ABS Control Module - J104-

❑ Component location: on

the ABS Hydraulic Unit -

N55- in the engine com‐

partment on the front

passenger side.

❑ Do not disconnect the

connector before suc‐

cessfully completing On

Board Diagnostic

(OBD). Switch ignition

off before separating

connector

Components:

♦ Electromechanical Parking

Brake Control Module -

J540-

♦ Transverse Acceleration

Sensor - G200-

♦ Rotation Rate Sensor -

G202-

♦ Longitudinal Acceleration

Sensor - G251- (depending

on vehicle equipment)

♦ The components cannot be

replaced individually.

❑ Removing and instal‐

ling. Refer to

⇒ “3.2.1  ABS Control

Module J104 / ABS Hy‐

draulic Unit N55 , Gaso‐

line Engine, Removing

and Installing”,

page 17

 .

2 - ABS Hydraulic Unit - N55-

❑ Component location: in

the engine compartment on the front passenger side

The ABS Hydraulic Unit - N55- consists of the following components:

♦ ABS Hydraulic Pump - V64-
♦ Brake Pressure Sensor 1 - G201-
♦ Valve block (contains inlet and outlet valves)

❑ The ABS Hydraulic Pump - V64- and valve block must not be separated from one another.
❑ Removing and installing. Refer to

⇒ “3.2.1  ABS Control Module J104 / ABS Hydraulic Unit N55 , Gasoline Engine, Removing and Instal‐

ling”, page 17

 .

3 - Brake Pad Wear Indicator Lamp - K32-

❑ Component location: inside the instrument cluster

4 - ABS Indicator Lamp - K47-

❑ Component location: inside the instrument cluster

5 - ASR/ESP Indicator Lamp - K155-

❑ Component location: inside the instrument cluster

6 - Brake System Indicator Lamp - K118-

❑ Component location: inside the instrument cluster

7 - Brake Lamp Switch - F-

❑ Installed location: on the master brake cylinder
❑ Removing and installing

8 - ASR/ESP Button - E256-

❑ Two versions, two component locations:

♦ As a button in the center console
♦ via the functioning surfaces in the Infotainment system menu

❑ ASR/ESP Button - E256- in the center console removing and installing. Refer to ⇒  Electrical Equipment;

Rep. Gr.  96 ; Controls; ASR/ESP Button - E256- , Removing and Installing .

9 - Diagnostic Connection

❑ Component location: driver side footwell cover

10 - Steering Angle Sensor - G85-

❑ Installed location: inside the steering gear
❑ The Steering Angle Sensor - G85- cannot be changed separately.
❑ Steering removing and installing. Refer to ⇒  Suspension, Wheels, Steering; Rep. Gr.  48 ; Steering Gear;

Steering Gear, Removing and Installing .

11 - Right/Left Front ABS Wheel Speed Sensor -G45- / -G47-

❑ Removing and installing. Refer to 

⇒ “4.1 Overview - Front Axle Speed Sensor”, page 35

 .

12 - Wheel Hub with Wheel Bearing

❑ The ABS sensor ring is installed in the wheel bearing

13 - Right/Left Rear ABS Wheel Speed Sensor -G44- / -G46-

❑ Removing and installing (FWD). Refer to 

⇒ “4.2 Overview - Rear Axle Speed Sensor”, page 36

 .

14 - Wheel Hub with Wheel Bearing

❑ The ABS sensor ring is installed in the wheel bearing