Sensor

ABS System Components For Front Axle, Removing And Installing

Note:
^ Removing and installing ABS system components is identical for FS 1/1 and FN 3 brake calipers.

1. ABS wheel speed sensor
^ Before inserting sensor, clean mounting hole inner surface and coat with lubricant, G 000 650
2. Wheel bearing housing
3. Hex socket head bolt, 8 Nm (70 inch lbs.)
4. Splash shield
5. Hex bolt, 7 Nm (62 inch lbs.)
6. Wheel bearing
^ Replace each time after removing refer to Transmission and Drivetrain; Drive Axles, Bearings and Joints.
7. Screw
8. Brake disc
9. Wheel hub with ABS wheel speed sensor rotor
^ Pressing out and in
10. Circlip

Wheel Speed Sensor For Front Axle, Removing And Installing

Removing
- Raise vehicle.





- Disconnect wheel speed sensor wiring connector -1-.
- Remove bolt -2- from wheel bearing housing.
- Remove wheel speed sensor from wheel bearing housing.

Installing
- Before inserting speed sensor, clean mounting hole inner surface and coat sensor with lubricant G 000 650.
- Insert speed sensor into mounting hole in wheel bearing housing and tighten bolt to 8 Nm (70 inch lbs.).
- Connect wheel speed sensor wiring connector.
- Turn wheels fully to left and right lock and check clearance of speed sensor wiring.


Front Wheel Speed Sensor Wiring, Removing And Installing

Required Special Tools And Equipment





^ VAS 1978 wiring repair set

Removing
- Obtain radio code on vehicles with coded radio.
- Disconnect battery.





- Remove Mass Air Flow (MAF) sensor connector -1- from air filter duct.
- Remove bolts -2- at air filter -3- and place filter to left side.
- On vehicles with Diesel engines, remove relay panel above brake booster.





- Release connector from control module (arrow -1-) and pull off (arrow -2-)





- Using a screwdriver, lift cover of multi-pin connector and remove.





- Using a small screwdriver, push purple latch in direction of arrow.








Pin assignment of harness connector T25 and ABS Control Module (W/EDL) -J104-





- Using extractor tool from wiring harness repair set VAS 1978, push out applicable terminals.
- Disconnect wheel speed sensor wiring connector.
- Replace faulty wheel speed sensor wiring.
- Connect speed sensor to speed sensor wiring.





- Secure speed sensor wiring (arrows).

Note:
^ Make sure the wiring is not twisted in the wheel well.

- Install pin connectors in connector housing.





- Using installation tool from VAS 1978, push individual wire seals to stop.
- Secure terminals by engaging purple latch and install cover of multi-pin connector.