ABS light Xantia

[captainslow72]

Hi all I have a constantly lit ABS light any ideas of how to sort it before MOT. car has been sat for 3 years I have changed brake pads and rear brake pipes Bled system brakes all work fluid level is good. I did knock off a rubber cap on back of drivers side brake below handbrake cable it was held on with cable tie have replaced it with new cable tie. Not sure if this is ABS sensor cover.

96 p reg Xantia estate VSX turbo

Thanks in advance Neil

[Northern_Mike]

http://www.frenchcarforum.co.uk/forum/v ... hp?t=26012" onclick="window.open(this.href);return false;

Will tell you how to test which sensor is at fault by removing the ABS ECU plug under the bonnet and testing resistance across various pins if you have a multimeter. The pin-outs for the series 1 car like yours are further down the page.

[Old-Guy]

And once you have identified the offending circuit, don't immediately assume it's a dud sensor. In my limited experience, 80% of the time it's a corroded connector. There's one on the subframe cross-member parallel to the rack, find it disconnect and test the sensor from this point. The other connector is the plug into the ECU. Clean up both and protect with WD40 (this is what it's for!).

Having said that, after the Green Lady had been sitting for 9 months the O/S/F sender had definitely died - wierd, no fault when she broke down, sensor open circuit when revived. I did wonder if a carelessly fitted tie-down strap had strained the cable (as well as breaking pad sensor wire) during the 2-stage recovery, but no visible sign of this.

[Hell Razor5543]

If you DO find it is a sensor DON'T get a cheapie replacement. I did on Gracie, and had to replace it within a year. The replacement cost me 3 times as much, and hasn't (yet) complained.

[Old-Guy]

If you DO find it is a sensor DON'T get a cheapie replacement. I did on Gracie, and had to replace it within a year. The replacement cost me 3 times as much, and hasn't (yet) complained.

On the basis that the sensor is a non-wearing electronic component that either works or doesn't and it's easy to test before fitting, if money is tight it's worth checking scrap-yards. Same side to side, front & rear different. Two different types for XANTIA (S1) with different change dates (RPOs) for front and rear, but different to XANTIA II (S2) which are all the same - but I'll bet there was some overlap with late S1s or early S2s!

[Hell Razor5543]

The problem I had with the cheapie was that the 'wire probes' that are in the 'nose' of the sensor were not properly sealed. This mean that they started to rust, and this caused the sensor to fail. The replacements were better made, the internal components are properly sealed, and they haven't played up.

[captainslow72]

Hi guys thanks for the info have done the test and 3 sensors are at about 1080 resistances 4th is 1160 would this be my faulty sensor? If not have you any other ideas? Thanks Neil

[Hell Razor5543]

That could well be it. The ABS system can be very picky re sensors. Which one is it? I hope that it is a front one (apparently the rear ones are difficult to replace).

[captainslow72]

Think it sorted moved her around today an ABS light gone off so will keep eye on it. I did also check all connecters that I could find. But think I have electrical fault somewhere as head lights come on by them self when car locked they then go off after about 1 min but came back on again. At some time just noticed so will have search through previous post. Thanks again guys
Neil

[Old-Guy]

A bad contact or possibly a mucky reluctor ring (that's the toothed wheel whose movement the sensor detects). Sensors work until they die. A word of warning, once an ABS fault is detected, even after the fault is fixed (or goes away!) the light stays on until the car has reached a sustained 20(ish) mph. This makes trying to find an intermittent ABS fault even more of a PITA than usual.

[wurlycorner]

That could well be it. The ABS system can be very picky re sensors. Which one is it? I hope that it is a front one (apparently the rear ones are difficult to replace).

Rear sensors are a complete pita .... if it's a rear i guarantee you'll end up wanting to get rid (but don't )

I can vouch for this - it's what made me give up on the car for a year half way through the job!
I did get it finished in the end however.

Guess what though - the car hasn't made it back on the road since I did that side and it's developed another ABS fault.

Can you guess which sensor is knackered now, out of the other 3???

[wurlycorner]

Two different types for XANTIA (S1) with different change dates (RPOs) for front and rear, but different to XANTIA II (S2) which are all the same - but I'll bet there was some overlap with late S1s or early S2s!

Yep, however the only difference I can see between them is that one has a metal housing (the earlier ones) and the later ones have a plastic housing.

I fitted a later one to my Activa (because they're cheaper) and it seems perfectly happy with it?

[Hell Razor5543]

For some reason the N/S/F sensor seems to be the one that fails the most. The following post could help;

http://www.frenchcarforum.co.uk/forum/v ... 11&t=26012" onclick="window.open(this.href);return false;

[Northern_Mike]

For some reason the N/S/F sensor seems to be the one that fails the most.

Yes. One mine too. I put it down to it being the first wheel that contracts all the detritus and water near the kerb. I wonder if it's the O/S/F sensor on LHD cars that fail first?

Sent from my GT-I9505