Intermittent ABS problem

[CitroJim]

It sounds to me like either the sensor was damaged then they did the bearing or they removed it and did not replace it properly. The fault is very similar to if the sensor tip is too far away from the reluctor teeth due to incorrect assembly.

Also, are the reluctor teeth clean and free of all grease and other debris, especially metallic debris. Check too the sensor tip is free of metallic debris.

[CitroJim]

That's it Mike, the reluctor ring on the driveshaft CV joint. On later Xantias it's quite common for them to rust and split. They can be fine until knocked, say, whilst doing the bearing job and they then split and leave a gap between a pair of teeth. Eventually they get loose, spin and then fall off.

Luckily they are replacable easily enough. Also, in pulling the driveshaft out of the hub it's quite easy for the reluctor ring to touch the tip of the ABS sensor and damage either. A good garage would have removed the ABS sensor first to avoid damage and in doing so they might not have reassembled it correctly and left it high, especially if the were not sure which side of it the heat shield went. Basically, the bit of the sensor with the mounting hole through it has to sit tight against the hub carrier and the tab of the heatshield goes on top, not between the sensor and the hub carrier.

[CitroJim]

I'll check the heatshield Jim, so its fittest otherwise it raises the sensor by a mm or two?

Absolutely so Mike, Yes.

[smc6]

I've had the same type of problem with my Xantia 1.8i 2000 and checked the resistance of ABS sensors in the ECU. There was no connectivity in the resistance on the Right Front - pins 19 and 20 as show on what I believe is the Mk2 connector.

I need to confirm that the right front on a right-hand drive Xantia is the O/S or driver's side of the vehicle. Is this correct?
Appreciate the help offered on this forum as it has helped fix a few problems on my Xantia.

[MJM]

I've always assumed that right hand is as from sat in the driver's seat. I had a sensor go on the nearside and this turned out to be the l/h side. As a further check before you buy another sensor, there is a connector under the wheelarch that the sensor plugs into. I would repeat your continuity test there to eliminate the loom between the abs ecu and this connector.

HTH

[smc6]

Appreciate the tip, I'll check it first. Thanks very much.

[CitroJim]

Yep, that's the pad wear light Mike..

If the pads are good then suspect a chafed wire between the pad and the connector block on the suspension strut.

They work by earthing the contact through the brake disc when the pads are well worn. Naturally if one of the wires is chafed and earthing it will have the same effect. The wires from the pads have to be routed with some care to prevent chafing.

[CitroJim]

That's what I'd reckon Mike.. You may find it happens on steering too.