ABS Sensor Wiring

3 amigos - RHR sensor fault code, but sensor itself appears OK (have cleaned it anyway / replaced, and get approx 2V when wheel spinning). Am also getting 1.5 ohm from harness at junction nearest the wheel. Thus looks as if problem between wiring connector at wheel and the Wabco unit?

What now? How do I ensure harness from wheel junction up to Wabco Module is OK? I can't see where the lead(s) come in within the engine bay.

Or am I on wrong track........?

Thanks

Redman

1. When u say "Wabco Module" what do you mean?.... if u mean SLABS ECU it's good, if u mean ABS modulator it's wrong
2. Measure resistance of the sensor, it must be between 950-1100 ohm.
3. The fact that u read 1.5 ohm backwards to the ECU is not strange cos the wires are connected to the ECU internals.
4. Disconnect C0505(pic below) and measure resistance then, it must be open circuit ...rear right sensor inputs are on pins 3 and 6, bridge these and then u must have closed circuit. If all the measurements are good and still sensor fault present put a new one and if after that still no joy i'm affraid u must replace the hub
In case i didnt understand well what sensor do you mean here are the pin disposals
C0505
1 Front left wheel speed Input
2 Front left wheel speed Input
3 Rear right wheel speed Input
4 Front right wheel speed Input
5 Front right wheel speed Input
6 Rear right wheel speed Input
7 Rear left wheel speed Input
8 Rear left wheel speed Input

Thanks for the wiring diagram - accessed the ecu; pulled the connector and tested pins as directed. Open / Closed circuit as one would expect (Closed is 1000 Ohm approx); when test the sensor itself then do get voltage reading. Which seems to indicate all is in order - except it isn't.

New sensor now only way forward?

Readman

I'm afraid it's not a sensor issue then but the hub... what specific code do u get on that sensor? ... if it's "air gap too large" then it's the hub ... quite similar with the front: www.discovery2.co.uk / Front Wheel Hub / Bearing Assy

sierrafery said:

I'm afraid it's not a sensor issue then but the hub... what specific code do u get on that sensor? ... if it's "air gap too large" then it's the hub ... quite similar with the front: www.discovery2.co.uk / Front Wheel Hub / Bearing Assy

Click to expand...

No,not always - it can be down to the sensor not fully seating because the bracket is very slightly bent where the o ring is a tight fit and wont let the sensor fully seat down.Throw the o ring away and use a small smear of silicone instead.