Front

47-0712 Removal and insatllation of front wheel-speed sensors

Model 124, 201

Preceding work:
Raise vehicle with lift platform (00-908)
Remove front wheel





- Turn Ignition off.

- Remove coaxial plug (L6/1x or L6/2x) from bracket (46) and unplug. Before plugging back together, inspect O-ring, replacing as necessary.

- Remove cable (27) from wheel house downwards through rubber grommet. When installing, ensure that the cable (27) is clipped in correctly. Refer notes on wheel speed sensor.

- Unscrew self-locking hexagon socket screws (30), replace, 22 Nm.

- Remove front wheel-speed sensor (L66/1, L6/2) complete with the cable (27). Before installing, coat wheel speed sensor and bore in steering knuckle (48) with Molykote Longterm 2. There must not be any metallic foreign bodies on the magnetic sensor. Check O-ring (28), replace if required. Ensure that the flange of the wheel speed sensor abuts the steering knuckle. Do not use force.

- Check wheel hub rotor for any damage and heavy contamination, replace wheel hub if required.

Model 124 (except 124.034/036)
Perform test program (42-0720).

Model 124.034/036
Read out fault memory, then erase (Chassis Diagnosis Manual, Volume 2).


Notes on wheel speed sensor cables
The fixing points or marking of the wheel sensor cables were revised several times in the course of development. Since 11/89 only the 3rd version is still available as a replacement part.





• 1st version = 1 color marking band which must be located beneath the clipping point (arrow).





• 2nd version = 2 color marking bands. The clipping point is located between them.





• 3rd version (since 11/89) with fixed reinforcement sleeves. When replacing a wheel speed sensor on vehicles built prior to 11/89 the brackets (29) and (32) together with the cable for the wear indicator (57) must also be replaced.





A red marking arrow (cutout) has been applied to the rubber grommet to center the wheel speed sensor. The function and design of the wheel speed sensor has not changed.

A 1st and 2nd version up to 10/89

B 3rd version as of 11/89