Any BMW specialists/techs here?

[Acidrop]

The ABS/DSC/brake lights on my E39 comes on/goes off intermittently. This is probably an MOT failure so I have to get it sorted.

So far I've done the following.

- Read fault codes which pointed to faulty front right ABS sensor. Replaced it but fault still there.
- Read codes again and brake pressure sensor fault came up. Replaced it but fault still there.
- Suspected faulty ABS module so replaced it, coded it to car and calibrated sensors. Fault still there!!
- Removed, inspected and cleaned ABS sensors. Also tested all 4 sensors from ABS module plug with multi meter on diode test to make sure wiring loom ok. All test ok.

I still consistently get one DSC fault code come up - brake pressure sensor interference.

Does anyone have any ideas as I'm close to driving the f*cking thing off a cliff.

[E-bmw]

Do you ever have speedo issues, such as occasional "drop-outs" with the speedo showing zero speed when moving?

[Acidrop]

E-bmw said:

Do you ever have speedo issues, such as occasional "drop-outs" with the speedo showing zero speed when moving?

Nope, never. And cruise control also works perfectly all the time. So I think that rules out anything untoward with the rear sensors/reluctor rings?

I'm wondering whether it could be one of the front reluctor rings. Initially it came up with a right front wheel speed sensor fault, even though the sensor is ok.

[Acidrop]

Bump.

[QuiteQuietCerb]

hi its most probably your abs control module, when it starts going those lights come on

[Huff]

Does the car run well otherwise? A friend had an e39 540 where the DSC switch being uncooperative (lamp lit all the time) turned out to be .. the cam sensor! Easy to check cam /crank sensor resistances with a digi voltmeter meanwhile.

Otherwise, for some reason it often seems to be the left side rear sensor (or joints in the wiring) which seems to cause probs in the E39 (yes, I keep notes on such things agains the day mine goes Rong!)

Edited by Huff on Thursday 11th February 21:17

[E-bmw]

QuiteQuietCerb said:

hi its most probably your abs control module, when it starts going those lights come on

Doesn't the OP say he has changed that in his first post?

[QuiteQuietCerb]

oh yes sorry didn't spot that

[SPORTSTER]

could be a wheel speed sensor?

[Acidrop]

E-bmw said:

Doesn't the OP say he has changed that in his first post?

Yes I've replaced the abs module and tested all sensors/wiring loom. What a pain in the backside! You would have thought with all the diagnostic tools it would be able to tell you what the problem was.

I'm going to order new wheel bearings and change them out(even though mine are perfectly fine ) as I don't really know what else to do.

[SPORTSTER]

What code reader are you using, get someone with an auto logic to detemine the exact code

[Acidrop]

SPORTSTER said:

What code reader are you using, get someone with an auto logic to detemine the exact code

I'm using INPA which I thought would more than suffice?