Abs

[Jane Blythe]

Hi help got an abs problem on reading the fault codes it says there is an electrical fault on the right front wheel on inspection cannot see anything wrong at the wheel sensor wiring does anyone know where the abs wires on the front feed back to, have done all the usual checks like changing over sensors but the fault keeps saying it's on the right front sensor many thanks jane

 

[Antm72]

Is that the only fault ? Mine reported this error and it was actually the abs pump module as i replaced the sensor and still got the issue .
Is it the only error shown ?

 

[Jane Blythe]

Hi just had the abs unit overhauled aalso showing a rear wheel speed detection fault both these faults were there before the unit was repaired by ecu testing the other problems that it went in for are gone so I'm thinking it has to be the wiring

 

[littlefeller]

does your car have asc or dsc?

 

[Jane Blythe]

does your car have asc or dsc?

Yes it does

 

[Jane Blythe]

Hi help got an abs problem on reading the fault codes it says there is an electrical fault on the right front wheel on inspection cannot see anything wrong at the wheel sensor wiring does anyone know where the abs wires on the front feed back to, have done all the usual checks like changing over sensors but the fault keeps saying it's on the right front sensor many thanks jane

 

[mrscalex]

Did you use BMW or at least a decent quality aftermarket sensor?

Budget sensors, including wheel speed sensors can be notoriously poor even brand new.

 

[Jane Blythe]

Did you use BMW or at least a decent quality aftermarket sensor?

Budget sensors, including wheel speed sensors can be notoriously poor even brand new.

 

[Jane Blythe]

Hi replaced wheel sensor with Atec one from Germany also have tried swapping the one from the other front wheel still get the same message, also have a spare pump fitted it and still get the same message on that one
(Pulling my hair out) think I have tried everything I can think of will have to try a BMW sensor as a last resort
Many thanks for your reply

 

[Jack Ratt]

Did you clean the hub ring that the sensor reads? It may be clogged up with brake dust or road dirt.

 

[Jane Blythe]

Did you clean the hub ring that the sensor reads? It may be clogged up with brake dust or road dirt.

Hi yes its spotless it is called the relucktor ring I think I've tried everything I can think of all the sensor wires have continuity up to the pump the pump has been back to ecu testing twice they say it's ok I.m now going to check every fuse and relay that's in the manual for the pump and sensors thanks for your reply

 

[mrscalex]

It sounds to me like you've checked all the usual things.

Does the error message change when you unplug the sensor? That ought to give you a clue either way if it's the sensor or something upstream.

 

[Jane Blythe]

Hi sure it's there plugged in or out thanks for your input

 

[mrscalex]

Hi sure it's there plugged in or out thanks for your input

A continuity test possibly isn’t adequate to identify a fault in the wiring harness.

I would imagine the sensor sends a variable pulse through the harness. So the control module might be more sensitive to unexpected resistance in the wiring harness.

This article may be worth a read for you.

http://m.autoserviceprofessional.co...t-abs-wheel-speed-sensors-what-could-go-wrong

I can’t pretend I wouldn’t be frustrated by now. But I think I would be concentrating on a more scientific test of the wiring harness.

My auto electric knowledge is fairly basic. But I would start with a wiring diagram in case there are any active components between the sensor and control module. But I would expect only passive.

Then I’d find the pins on the control module connector and possibly do a voltage drop test.

One other thought is that the harness connector for the sensor is damaged and not making contact properly. So you can prove it okay. But the pins aren’t inserting properly when the sensor is connected.