Wanted ... Rear ABS sensor for BX

Dave1 · Post by **Dave1** » 11 Jun 2007, 23:29

Need a rear ABS sensor for BX. Anyone got a working one they do not want or know where to get one.

(I know you can buy then new)

jeremy · Post by **jeremy** » 12 Jun 2007, 00:37

Have you tried repairing yours? Often the cable corrodes through (outer screen due to poor outer skin). Cut the cable somewhere convenient and meter the sensor side - to see if the bit left works - then solder a length of multi strand co-ax in and insulate carefully - do the same the other end and if the sensor itself was OK it'll now work. I've done 2 BX rear ones in situ - and you can route the new cable in to the car so the top joint can be made close to the plug under the back seat.

citronut · Post by **citronut** » 12 Jun 2007, 19:07

usualy the wire fractures were it is flexed at the point the arms and legs pivot,most of the time it is not the sensor itself
regards malcolm

Dave1 · Post by **Dave1** » 13 Jun 2007, 20:42

Thank you both for your help. I sort of discounted splitting it because somewhere I read that the rear ones tend to give up at the sensor due to some corrosion build up around the sensor itself. However, my BX has not seen rain in the last 5 years so it may just be the movement of the car. I had a problem with a front one last year (the sensor definitely gave up and I am sure it was the front as I tested it directly) bought the new part and then upon fitting it last week, found the rear one gone. Have tried testing and moving the cable at the same time etc. but no joy.

Anyway assuming it is the cable, do I need to buy any specific type of co-axial and how to I go about soldering it? IE the inner bit and the outer bit.

AndersDK · Post by **AndersDK** » 13 Jun 2007, 23:00

This topic is changing ...

I find it better move it to the repair & technical section, as it looks promising whats come up now

Dave - the cable is not really needed to be special, as electronic wise the receiver end in the ABS ECU is made differential to cope with electric interference.

The problem is purely mechanical stress on the cable, which makes the isolation to detoriate and then water with road salt gets into the party and mess up the dance ...

You may have noticed the cable feels a bit strange in your hand - like very soft rubber. Its a silicone rubber cable - like modern spark plug cables. If you cand find a long stainless steel spring - you can use this as a cable outer protective sheath. This is often found on power cords for industrial equipment. Also found on pressure airline equipment.

jeremy · Post by **jeremy** » 14 Jun 2007, 00:18

I found I had 3 failes sensors on mine - all with cable problems. To solder them I stripped the co-ax cable to leave about 2 inches of the centre conductor exposed and teased the screening so I had wires rather than the braid. The object was to produce a join about 1 inch long when finished - so I twisted the centre conductors together and soldered them, insulated them carefully using a cloth tape and built that up to the original size. I then put a layer of plastic tape on, spread the screen over it and twisted the wires from each side together in several twists spread round the centre and soldered them and then insulated that with plastic tape.

I put a plastic sheath over the whole job - mainly as I had a large quantity of the stuff left over from another job. I then taped the ends of this to the co-ax to seal it.

One onf those I did 7 years ago is working undisturbed, the other back sensor itself failed after about 4 years and I had to re-do the front one about 6 years ago as I got the routing wrong and it kinked the new section of the cable and broke internally. Better routing sorted that and its still working.

Dave1 · Post by **Dave1** » 15 Jun 2007, 23:40

Thanks for that, very helpful. I will look into it. Would be nice if it was just the wire and I fixed it. I will let you know but appears the rain is going to keep the job at bay for a while

Dave

jeremy · Post by **jeremy** » 16 Jun 2007, 07:53

Thinking back I tested the sensors / leads by connecting one side of the meter to the centre core at the plug - then used a sharp probe connected to the other to see where the sound screen was. I started with the probe near the plug and worked away from it - and when you get a reading - you've found sound cable.

Dave1 · Post by **Dave1** » 16 Jun 2007, 18:08

Sadly it seems to be the sensor itself. I cannot get any reading at all with the meter at any point down the lead. Even taken it back to the final clip holding it in place near the disc.

Looks like a replacement one at some point but definitely worth a try and thanks for all your help on this one