Abs sensors

Jmcc · Post by **Jmcc** » Sun Oct 02, 2011 9:12 am

I have an intermittent ABS light issue. PO warned me and said it was one of thd front sensors. He has a new, genuine Citroen sensor he'll sell me but at a fairly high cost (what he paid). Is this necessary or are there any aftermarket sensors available? Car I'd 1993 1.7TZD.

Thanks,

James

Post by **mat_fenwick** » Sun Oct 02, 2011 9:29 am

Unfortunately so. I've not read of anyone on here who has found a suitable non OE replacement as I believe the senor was only fitted to the BX, making it uneconomic for a pattern part to be made.

IIRC the Citroen price is in the region of £100! It may well not be the sensor, but an internal break in the cable. However, finding the break is probably the issue...

ken newbold · Post by **ken newbold** » Sun Oct 02, 2011 3:55 pm

First thing would be check your connections to the sensor.

You'll find them down the inside of the inner wings. Like all electrical connections, they can go moldy.

Jmcc · Post by **Jmcc** » Sun Oct 02, 2011 4:57 pm

Chap reckoned the sensor owed him £200 and that they were almost impossible to get hold of now, other than secondhand. Could be a connection/break in wire as it is an intermittent fault. Might get one of the sparkys at work to take it back to the sensor and graft a fresh wire in (and possibly new connectors).

Cheers,

James

Kitch · Post by **Kitch** » Sun Oct 02, 2011 10:23 pm

You can diagnose faulty sensors with a multi-meter using the multi-plug at the ABS ECU. If you check out the bx 16v site, there are some details in the download section. You can test the sensors to make sure they\'re operating at the right resistance at the ECU pins (even a bit of shit on the end of the sensor can mess up the signal). That tells you whether you have an issue or not, because the ECU is the last port of call and controls the ABS lamp. If one of the sensor feeds is reading wrong, you probe further by testing all the sensors at their connectors (fronts under the bonnet, rears under the back seat). This highlights any issues in the wiring between ECU and sensor plug, so if they\'re suddenly all ok you know the wiring is up the swanny.

If one is found to be reading wrong, equip your multi-meter pin with a very fine sewing-needle type pin and pierce the insulation or the wiring right next to the sensor itself, or worst case chop it and check the wiring (you can rejoin it later if needed). If the reading is still wrong, the sensor is kaput. If it\'s ok, then the issue is in the wiring between the sensor and the connector, meaning all you need to do is repair or replace the wire rather than shell out on a new sensor. If you can find one!

Does that make sense?!

Jmcc · Post by **Jmcc** » Mon Oct 03, 2011 11:12 am

Perfect sense! Thanks.