ABS problem

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billgatese30
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Mon Oct 28, 2013 7:02 pm

Right, quick question really.

I had an ABS ring disintegrate on me and try to do an impression of something from Alien with the brake disc backing plate. Any way, now I have no ABS ring on the drivers front wheel, all the other 3 are working correctly (I am assuming!).

Will this just throw up the ABS warning light after a few yards and otherwise be ok to drive, or is it going to get its knickers in a twist every time I try and brake and it thinks my drivers side front wheel is locked! I.e. do I need to remove the sensor or remove any relays/fuses to disable the ABS completely or will it recognise there is a fault and not try to do anything stupid when I don't want it to

Thanks

Chris :D
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Brianmoooore
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Mon Oct 28, 2013 7:17 pm

The ECU should detect that the pulses from the right front sensor are missing as soon as you move, when the brakes are not applied, turn on the fault light, and switch the ABS off.
Braking should be normal, less ABS.
billgatese30
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Mon Oct 28, 2013 7:44 pm

Awesome. Thanks Brian thats me sorted for getting to work then if that's the case. Cheers.
daimlerman
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Tue Oct 29, 2013 7:59 am

Bear in mind that the MoT man will not be happy with the light coming back on,and the only 'proper' fix is a new front hub....
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harry_p
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Tue Oct 29, 2013 11:26 am

The system should work out quite quickly that something is wrong, and as Brian says, put on the light which means the system is off.

I had similar in my lancia but occasionally it would take a little while for it to figure out what was going on which could leave you with virtually no brakes until the light came on!

As the lancia system was a very similar Bosch one, and a similar age to the e30s, I would imagine the brains are very similar too, so be carefull until you know what it's up to.
cheers,

harry
Widge
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Tue Oct 29, 2013 12:13 pm

I had this problem recently pre MoT. It was a rusted up ABS ring.
To begin with the ABS was still active but would kick in at about 1mph just before I stopped at a junction, a judder being felt through the pedal as the ABS pump modulated thinking the front right was locked up.
Latterly the ABS light just came on and the ABS was deactivated.

I had a new wheel bearing to go on the car to fix the problem, as the ABS ring on the front is part of the wheel bearing (BMW obviously aware it is a consumable part - the ABS ring that is!). But I managed to remove the sensor and clean the ring of rust with a screwdriver and a small wire brush, ABS has been working ever since, and the wheel bearing is now on the shelf as a spare for when the bearing actually goes!

Do no need to change the hub, just the wheel bearing.
billgatese30
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Tue Oct 29, 2013 5:09 pm

Somehow I think cleaning this one with a wire brush won't quite cut it.

Image

And I realise I'll need a new bearing before MOT time but I'll be close to needing brake pads by that point too so will probably combine the two jobs pre MOT :cool:
bss325i
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Tue Oct 29, 2013 7:23 pm

Change that crusty back plate/heat shield at the same time as the bearing/hub is coming off.
http://www.bmrperformance.co.uk

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