Wheel sensor (ABS) - removal and refitting

Note: A new O-ring must be used when refitting a sensor.

Front wheel sensor
1 Apply the handbrake, loosen the relevant front roadwheel nuts, then jack up the front of the vehicle and support on axle stands (see “Jacking and Vehicle Support”). Remove the roadwheel.

2 Working under the bonnet, unclip the ABS wiring loom from the chassis side member, and disconnect the wheel sensor wiring plug.

3 Unscrew the mounting bolt and withdraw the sensor (see illustration).

22.3 Unscrew the mounting bolt and withdraw the front wheel sensor - ABS
22.3 Unscrew the mounting bolt and withdraw the front wheel sensor - ABS

4 Refitting is a reversal of removal, bearing in mind the following points.

5 Clean the bore in the hub carrier, and smear the bore and the sensor with lithium based grease.

6 Use a new O-ring seal when refitting the sensor.

Rear wheel sensor
7 Chock the front wheels, loosen the relevant rear roadwheel nuts, then jack up the rear of the vehicle and support on axle stands.

Release the handbrake and remove the roadwheel.

8 Working inside the vehicle, lift up the rear seat cushion, then remove the side kick panel and fold the carpet forwards to gain access to the wheel sensor wiring plug (see illustrations).

22.8a Remove the side kick panel (securing screws arrowed) for access to the
22.8a Remove the side kick panel (securing screws arrowed) for access to the rear wheel sensor wiring plug - ABS

22.8b Rear wheel sensor wiring plug (arrowed) - ABS
22.8b Rear wheel sensor wiring plug (arrowed) - ABS

9 Remove the wiring plug from its clip, and disconnect it.

10 Prise out the floor panel grommet, then feed the sensor wiring through the floor panel.

11 Free the handbrake cable from its clip on the suspension lower arm.

12 Where applicable, disconnect the wiring to the disc pad wear sensor.

13 Unscrew and remove the bolt from the forward caliper guide pin, while holding the pin stationary with a spanner.

14 Swing the caliper rearwards to gain access to the wheel sensor.

15 Unscrew the bolt securing the sensor to its mounting bracket.

16 Refitting is a reversal of removal, bearing in mind the following points.

17 Clean the bore in the sensor mounting bracket, and smear the bore and the sensor with lithium based grease.

18 Use a new O-ring seal when refitting the sensor.

    See also:

    Starter motor - testing in the car
    Note: Refer to the precautions given in “Safety first!” and in Section 1 of this Chapter before proceeding. 1 If the starter motor fails to operate when the ignition key is turned to the appropria ...

    Brake fluid renewal (Every 36 000 miles or 3 years)
    Warning: Brake hydraulic fluid can harm your eyes and damage painted surfaces, so use extreme caution when handling and pouring it. Do not use fluid that has been standing open for some time, as ...

    General information
    1.6 litre engine The 1.6 litre CVH engine was introduced in September 1991, to replace the 1.6 litre SOHC engine used previously in the Sierra range. The engine is broadly similar to the 1.8 litr ...