Hi All,

I have a 1994 320i Auto Saloon (129000 mls) The ABS warning light keeps coming on and going off at different intervals (there is no pattern to the timing) I have tried to remove the rear sensors but after removing the retaining bolts I cant get them out. Any tips on removing them or should I be looking for something else. Can they be tested?

Because of the dificulty you're having trying to remove them, they must've been in for quite a long time if not originals...

Having said that, try cleaning them "in-situ" and also the "fins" on the inner side of the discs... Cheap fix if it works ;)

How old is the fluid?

Because of the dificulty you're having trying to remove them, they must've been in for quite a long time if not originals...

Having said that, try cleaning them "in-situ" and also the "fins" on the inner side of the discs... Cheap fix if it works ;)

How old is the fluid?

Thanks. Ive had the car for 10 years and Ive never changed them. Could you be more specific by "in-situ" and what are the" fins" on the inner side of the disc? At the moment its on axle stands as Im renewing the the discs and all I can see is the sensor with no visible access, just the back plate. Does this have to come off? The fluid is about 5 years old, but why do you ask? Anyway thanks for answering my post. Cheers!

Right, I would flush the fluid with new stuff.

Remove the plate and clean what you can, thoroughly.

Agreed give everything a clean and your be fine

Agreed give everything a clean and your be fine

Thanks Fellas,

Ill try that tomorrow and let you know how I get on. Ive been in the bmw lounge and seen the same problem so Ive got two lines of attack! Whats your view on buying a diagnostic tester to use with a laptop? Have you got/used one? If so what one have you got/used?

Thanks for replying.

Hi Pal, i would hold off buying the diag software, i have the same issue as you and i have also got the 1994 320i, i bought the diag software from ebay.... see my other thread... http://www.bmwowners...stics-software/ i cant get it to work... so not sure it is compatible with my ecu.... waiting on confirmation from Ian and what software version he has... i bought the 1.3.6 software and scanner...

So far i have replaced both front sensors and still have the issue....... when Dabsy says clean the fins in inside of disc... there doesn't seem to be any... i have had the disc off completely and the ABS sensor actually goes into a totally enclosed housing and i can only guess that you have to take the hub and wheel bearing off to get at that...

CarSoft !!

CarSoft !!

Carsoft??? do you have any more details you can give ta....

No need for info on Carsoft.... just read a some details on what it is, sounds like a very good piece of software...

Hi Pal, i would hold off buying the diag software, i have the same issue as you and i have also got the 1994 320i, i bought the diag software from ebay.... see my other thread... http://www.bmwowners...stics-software/ i cant get it to work... so not sure it is compatible with my ecu.... waiting on confirmation from Ian and what software version he has... i bought the 1.3.6 software and scanner...

So far i have replaced both front sensors and still have the issue....... when Dabsy says clean the fins in inside of disc... there doesn't seem to be any... i have had the disc off completely and the ABS sensor actually goes into a totally enclosed housing and i can only guess that you have to take the hub and wheel bearing off to get at that...

Thanks for the input. Yea I think I'll give the diagnostic whatsit a miss. Because I wanted to change the rear discs I have concentrated on the rear sensors. There is no access to them as they are behind the hub so I thought I would battle on and try to change them. WELL! if you have to go down this very rocky road then don't bother with a swear box, get a SWEAR BUCKET! They were an absolute pig to get out. The way I managed to do it was I removed the retaining bolt and forced an old screwdriver underneath and then broke the top off of the sensor. I then worked the same screwdriver down the side and prised it out bit by bit. I also slid a larger screwdriver between the top of the halfshaft and gently forced it up from underneath. It took me ages but I managed to replace both rears. I have also replaced the fluid. I bought the two sensors for £35.98 on ebay er' I can't find the address at moment. So far it seems to have cured the problem but I'ii give it a good run out on the weekend and let you know if it worked. Cheers

Well done mukka... We like the "Hands-On" approach :)

Smashing, just driving a few meters would light the ABS up again if there was still a problem so if you no lighty no faulty... i had the same issue removing the front drivers..... once there stuck there well and truly stuck no option but to smash them out.... maybe i should of started on the rears... thanks for the update though steve...

some abs systems have the other half of the sensor in the wheel bearing .... its a magnet of some kind i think so the fins dabs was on about might not b on yours or a ring round the driveshaft that looks like a cog the top of the teeth are what the sensor reads. if u have the time to leave it over night run wd40 all round the sensor and next day gently try to twist the sensor out ..... i usualy break them so have new ones ready or another way to get them from the shop

as for brake fluid i change mine every 2 years along with the gear box n back axle but im just anal lol

Deffo fluid change - And you're right Kirby, the rotor-fin system was unreliable in that they clogged up to often - magnet system was much cleaner way to send sig. !!

some abs systems have the other half of the sensor in the wheel bearing .... its a magnet of some kind i think so the fins dabs was on about might not b on yours or a ring round the driveshaft that looks like a cog the top of the teeth are what the sensor reads. if u have the time to leave it over night run wd40 all round the sensor and next day gently try to twist the sensor out ..... i usualy break them so have new ones ready or another way to get them from the shop

I left them for 3 days with as much WD40 as I could get on. Also squirted some more every day, but the little darlings didn't want to come out! and also its got what looks like a cog underneath the sensor

Well done mukka... We like the "Hands-On" approach :)

I wish they were someone elses hands!