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ABS SENSORS

Posted: Thu Jan 26, 2012 4:19 pm
by marco2002
Hi
Had a problem with the abs yesterday. When i was driving the abs light came up on dashboard and stayed on for a while and mfd flashed up message "abs fault" followed by a beep. I stopped driving left car for about 30mins came back started car up again then it went out and hasn't come back since yesterday. I was thinking of giving the abs sensors a clean and also check/clean abs rings on the cv joints on the front end. Last time i cleaned the front sensors they were caked in crap so i'm hoping it might be a simple fix. The abs rings were in good condition the last time i looked and there were no cracks.

Is it easy to clean the abs sensors on the rear of the car? Haven't touched the ones on the back since i've had the car. Don't seem to be having much luck this week side airbag light on dashboard is on now so that will be another job to do..... have to check the connectors under the passenger seat. Seems a bit of a coincidence that the electrics are playing up? Any advice about the abs sensors appreciated as i'm eager to get it sorted.

Thanks

Re: ABS SENSORS

Posted: Thu Jan 26, 2012 5:32 pm
by keppler
Remove the rear caliper (two bolts). Then remove the disc/drum (two small screws on front face). You should be able to see the abs sensor sticking through the back cover plate and the ring will be very accessible. It may be a toothbrush job but it should be easy enough.

Re: ABS SENSORS

Posted: Fri Jan 27, 2012 2:41 pm
by marco2002
thanks for the advice about the rear sensors. AA man came and looked at the car couldn't find anything wrong with the steering or suspension. Unfortunately he didn't have a code reader on board to find out why the abs light is on. Just been to the local garage and he read the code off for me and it said its flagging up the drivers side as faulty. They suggested cleaning the sensor and abs ring and seeing how it goes if that doesn't work then it would be the sensor itself which is £43 inc vat from GSF.

Re: ABS SENSORS

Posted: Fri Jan 27, 2012 8:18 pm
by jasper5
I had a rear sensor fail on my 407 more than a year ago.The light stayed on all the time.

Every now and then the ABS light comes on for a short while then goes out again (usually when it's been out in heavy rain).

I haven't bothered with it as it's just a minor irritation.

Re: ABS SENSORS

Posted: Sat Jan 28, 2012 2:00 pm
by marco2002
Just cleaned the abs ring and sensor this morning it didn't work light is still on and odd intermittant so i've got another sensor from the breakers yard for £10. I'll try and fit it and see if that works. lol

Re: ABS SENSORS

Posted: Sun Jan 29, 2012 11:11 am
by marco2002
Hi
Just fitted another abs sensor o/s/f and the abs light is still intermittent today.Ii think there could be a bit more to this than meets the eye. I'm going to see the mechanic on tues. He said could point me in the right direction and read the code off. At least it hasn't cost too much so far.

Re: ABS SENSORS

Posted: Mon Jan 30, 2012 11:51 am
by marco2002
Off to the garage tommorow for a diagnostic so hopefully i'll have a idea of whats wrong. The abs light is still intermittent. lol

Re: ABS SENSORS

Posted: Tue Jan 31, 2012 9:33 pm
by Steve406HDi
Following with interest, be keen to see what the problem turns out to be.

Re: ABS SENSORS

Posted: Wed Feb 01, 2012 1:07 pm
by marco2002
hi

After taking the pug for a diagnostic its not the o/s/f abs sensor thats faulty its the o/s/r! Mechanic said the other other garage gave me duff info with their code reader/diagnostic even though they didn't charge for plugging it in its wasted a lot of my time 40mile round trip to breakers and probably about an hour altogether cleaning the abs ring and sensor then replacing the front abs sensor which wasn't even faulty. I've just ordered a new o/s/r sensor from ebay so hopefully it will be here for the weekend. Next time i know which mechanic to go to. lol . At least it is an easy fix.

Apparently when he tested it its only below 30mph that the sensor doesn't work that makes sense as the abs light comes on at low speed. It cost £30 to have the diagnostic done so it was well worth it just to find out what was wrong. I'm starting to think having the pp2000 could save a lot of money in the long run. Anyway I also have the side airbag light to sort out so i'll be cleaning the connectors under the passenger seat at the weekend and using some contact cleaner. Mechanic said any lights that are showing on the dash now are mot fail like abs,eml or airbag .......

Re: ABS SENSORS

Posted: Sun Feb 05, 2012 1:33 pm
by quemlar
Hello Folks,

I have a 2002 2.0L 406 Diesel and the Orange ABS warning light is on. Its been on since I bought the car. I know the previous owner and he says an ABS sensor needs to be replaced. I had been putting it off and its been so long he can't remember if its the front right or front left is at fault. I just spent a lot of money getting the suspension repaired and forgot about the ABS fault. The car is due for NCT same as the UK MOT and he tells me it will fail the test if this isn't fixed. I work with electronics and I can solder and troubleshoot circuits and wondering if I could replace it myself. Could someone tell me where to find the sensors and what tests can be done.

Appreciate any tips offered.

- Chris

Re: ABS SENSORS

Posted: Sun Feb 05, 2012 5:55 pm
by jasper5
It won't fail the mot for the warning light until 1st April, but it will be an advisory.

Re: ABS SENSORS

Posted: Sun Feb 05, 2012 6:41 pm
by marco2002
Hi

Just an update i've stripped the rear brake assembly as the caliper sliders were seized cleaned it all up. Took the disc off and ive now found one of the spring clips that holds the handbrake shoes in inside spinning around loose inside the disc. I've put it back where it should be and noticed that the abs ring has a bent tooth and a couple have nicks in them the abs sensorpin also looks bent. I've got a new one here so i'll replace that tommorow.

Any advice on getting the sensor out the little bolt that holds it in came out easy enough but the sensor looks like its welded to the place it mounts onto? I was thinking about using a very small chisel needs something small and pointy to wedge in between i did try using a screwdriver to wedge in between but it didn't work. Bloke in the garage said they can be a pig to get out (famous last words). So it looks like i'll need a new bearing/hub at some point. I was amazed how much damage a small clip spining around inside the disc can do. Lucky i spotted this today. The brake shoes themselves are okay i've sanded them lightly and cleaned it all up. I'm cleaning the disc and pads up tonight they are still okay for a bit longer.

Thanks

Re: ABS SENSORS

Posted: Sun Feb 05, 2012 6:47 pm
by lozz
Ive drilled abs sensors out in the past.
they can be apain,

iwas shocked how much copper wire is in them

Re: ABS SENSORS

Posted: Sun Feb 05, 2012 7:48 pm
by keppler
I used an extension from my 1/4 inch socket, fitted snugly over the pin and hammered it out.

Re: ABS SENSORS

Posted: Mon Feb 06, 2012 5:01 pm
by marco2002
Hi

Managed to get the o/s/r abs sensor out and put the new one in. The old one snapped as i pulled it out left the other half still intact in the hole managed to get a small drift through one of the wheel nut holes and lined it up with the pin and bashed it straight through with a small hammer. Worked a treat. Gave the hole and the bit where it sits a really good clean up. At least i know what to do if the other side goes. The front abs sensors are a lot easier to get out. Going to take it out later to see it abs light goes out. Next job is a new o/s/r wheel bearing.......