ABS System Components For Front Axle, Removing and Installing

ABS system components for front axle, removing and installing

Note: Removing and installing ABS system components is identical for FS III 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 in. lb)





4- Splash shield
5- Hex bolt, 7 Nm (62 in. lb)
6- Wheel bearing
^ Replace each time after removing
7- Screw
8- Brake disc
9- Wheel hub with ABS wheel speed sensor rotor

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 in. lb).
- Connect wheel speed sensor wiring connector.
- Turn wheels fully to left and right lock and check clearance of speed sensor wiring.

ABS wheel speed sensor rotor for front axle, checking
- Raise vehicle.
- Remove wheel. Rotate brake disc and check whether wheel speed sensor rotor is damaged or dirty.
- If rotor is damaged, remove wheel hub with rotor and replace.

ABS wheel speed sensor gap, checking
- Raise vehicle.
- Remove wheel.





- Turn wheel hub and measure distance between rotor and speed sensor, -dimension a-, all around.
^ Dimension a = 0.3 mm (0.0118 in.)
- If the rotor is not true, remove wheel hub with rotor and replace.

Front wheel speed sensor wiring, removing and installing

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-

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 senor 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.