Volkswagen Workshop Service and Repair Manuals

• ABS hydraulic unit (N55)

The hydraulic unit consists of the components:

• ◆ Hydraulic pump (V64) with hydraulic pump sender (G101)

=> is checked by the self-diagnosis

• ◆ Valve block (contains the in/outlet valves, for ABS/EDL additionally the valves for the differential lock and the pressure control switch, which has been deleted from 07.93).
• ◆ The hydraulic pump (V64) and valve block must not be separated from one another

=> Running gear; Repair group 45

• ◆ When changing the hydraulic unit always seal the old part with the plugs from the repair set Part No.
  1H0 698 311
• ◆ Hydraulic unit multi-pin connectors
  

• EDL series resistance (N159)

=> is checked by the self-diagnosis

• ◆ Location: On the hydraulic unit (N55)

• Brake pedal position sender (G100)

=> is checked by the self-diagnosis

• Brake light switch (F)

=> is checked by the self-diagnosis

• ◆ The brake light switch is open in the rest position;
• ◆ Adjusting => Page 01-87

• ABS warning lamp (K47)
• ◆ Location: In the dash panel
• ◆ Function:
• ‒ The ABS control lamp (K47) lights for a few seconds after switching on the ignition
• ‒ If a fault is recognised (e.g. speed sensor open circuit) it remains on
• ABS relay (J102)
• ◆ Location: Above the relay plate
• ABS hydraulic pump relay (J185)
• ◆ Location: Above the relay plate
• EDL relay (J310)

=> is checked by the self-diagnosis

• ◆ Location: Above the relay plate

• ABS control unit (J104)

=> is checked by the self-diagnosis

• ◆ Location up to 01.93:
  in footwell, front left below floor mat in front of passenger seat
• ◆ Location from 01.93:
  under the rear seat, right
• ◆ Checking the multi-pin connector to control unit
  
• ◆ Do not disconnect connector before successful interrogation of fault memory, switch ignition off first.

• Impulse wheel for rear right and left speed sensors
• ◆ Installation instructions => Item 13
• Impulse wheel for front right and left speed sensors
• ◆ Installation instructions => Item 13

• Rear right/left speed sensor (G44/G46)

=> is checked by the self-diagnosis

• ◆ Installation instructions => Item 13

• Front right/left speed sensor (G45/G47)

=> is checked by the self-diagnosis

• ◆ Before inserting the sensor clean the inner surface of the sensor mounting and coat with lubricating paste
  G 000 650
• ◆ When connecting the speed sensor wire ensure it is not twisted in the wheel housing
• ◆ Securing bolt tightening torque;
  10 Nm

• Diagnosis connection
• Vehicles from 08.93
• ◆ Location: The diagnosis connection is located behind the cover on the right next to the ashtray
• Diagnosis connection
• Vehicles to 07.93
• ◆ Location: Below the heating/ventilation controls, next to the heated rear window switch