97 Xantia - Intermittant ABS light

sweyn · Unread post by **sweyn** » 23 Jun 2003, 16:58

Variation on a theme. My 1.8i SX has a peculiar ABS light problem:
Light tests OK on startup, then goes out as normal.
After a couple of minutes of driving light comes on , sometimes stays on, sometimes goes out again after a minute or two.
ABS works OK all the time as far as I can tell- I can feel pulsing.
A driveshaft was replaced recently. I've been told that a mismatch of sensor segments might cause this problem.
Any ideas ?

Unread post by **alan s** » 23 Jun 2003, 17:58

When I bought my BX 3 years ago, the ABS light stayed on all the time and the ABS didn't work.
The previous owner had spent big $$$$s having it all checked out & they concluded it had a fault but they couldn't find it, which was good enough for them to be charged A$560 just for the priveledge of letting them try to find it.
I eventually thought I'd try to find the problem just so I could say that I had ABS that actually worked as we don't have the imposition of this scam you guys call an MOT (yet) so there was no necessity to have it operational.
The first thing I did was clean the serrated wheels that the sensors operated on; that gave me a light on - light off situation. Finding a broken bracket that holds the sensor lead, I then held the lead in position which gave me; light on, light off and until I turned the wheel in one direction; light back on again.
With light on I had no ABS but when off I did. If the light went off then came back on again, the only way I could get the light to go off & hence operational ABS was to stop, switch off the ignition & restart the car.
I would be very surprised if the light comes on that it will go off again & still operate the ABS. My suggestion would be that if the ABS works in that situation, then I would guess that the problem is with the actual bulb and/or its socket or holder than with the actual ABS system.
If however it is in the system and this is proven by the ABS not operating when the light is on, then cleaning the serrated wheels followed by a check of internal breaks possibly in the region where the lead comes out of the sensor should be a good place to start.
Alan S

MarkS · Unread post by **MarkS** » 24 Jun 2003, 02:30

when a wheel sensor is getting near to being no good at all it can give just the symptoms you are describing, these can be checked with a multimeter, although I dont know the settings.

adrianeaton · Unread post by **adrianeaton** » 25 Jun 2003, 18:32

My BX 16V had an ABS warning light that would come on and go off of its own accord. There WAS an actual fault with it, as when coming up to junctions the ABS would operate at very low speed and pedal pressure.
Mine got progressively worse until the light would come on and stay on. On investigation it turned out to be the front nearside (left) sensor - the insulation around the sensor cable had been eaten through by battery acid or similar and the cable was earthing on the body of the car. £10 for a 2nd hand sensor and no problems since

Adrian