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Just changed the rear pads today, really straight forward and far easier than on any other car I have done them on BUT, mt brake pad sesor light is stil showing on the dashboard. No, I did not change the sensor even though I do have a new one because I left in in my flat (London) and changed them down here (Cornwall) so obviously when I remembered I had forgotten it I was not keen on turning around and driving 200 miles for it. It looked in OK shape.

Is there some sort of reset procedure? Or should it simlpy of turned itself off?

Thanks.

No reset procedure, but you know there are two of the little buggers (left front / rear right), so could the other one have worn through?

Checked the front pads and they have plenty of life left in them so will pull out the rear sensor and replace it. Can't believe I forgot the damn sensor!! Even remembered to take some copper grease with me for the backs of the pads and the hubs

Oh cock!!!!!!!!!!!!

Has anyone here actually changed this bastard sensor? The bit that goes into the pad is fine but the other end (plug)!!!! f**k, how the hell am I supposed to get fingers to it!! Argh!!!!

the sensor plug is just a box on the wheels arch, open the box, twist and pull and the old plug comes off. then reverse for putting it on.

i changed my front one, was really easy. have you took your wheel off to make it easier?

Yes, the wheel is off and I have had my head underneath so I can see - and I have located that box I think you are talking about but am struggling to get in it. Lots of swearing going on half an hour ago... stopped now thanks to a coffee and a bear shaped chocolate covered shortbread biscuit! Will have another go in a minute...

maybe use a screwdriver to get in, if they havent been opened for ages they might just get a bit sticky. if i remember right there are 2 little clips holding it closed

on a brighter note, i know the biscuits your on about and they are amazing!!

OK, some success. To get to the rear one you need to remove the plastic trim under the wheel arch – you can then get hands in and see what is going on. Unfortunately I tried doing it before I worked this bit out, got my fingers on what I thought was the plug, pulled it out blind only to discover the ABS light sensor also lives in the same box. So now I have successfully replaced the brake sensor, the brake wear light is off, but now my ABS light and the "your doing a skid" light is on.

I took some photos and will put them up here later for future reference

Accidentally pulled it off (the plug) while changing the brake wear sensor. Put it back on but now the ABS light and warning triangle light won't turn off. Now the sensor was fine before I unplugged it – what have I done?

PetKiller wrote:Accidentally pulled it off (the plug) while changing the brake wear sensor. Put it back on but now the ABS light and warning triangle light won't turn off. Now the sensor was fine before I unplugged it – what have I done?

Sorted. just needed to hold the DSC button down and it reset.

Okay, I had a pig of a morning doing this simple task simply because I did not know how to get to the plug end of the brake wear sensor - unlike the one for the front brakes it is hidden and hard to reach, you cant see it through the access panel and it is hard to just do it by feeling it because the space is so cramped. You also run the risk of undoing the wrong sensor as the ABS one is housed in the same box. So, as I was doing it I took some photos and uploaded them here tol hopefully save someone else an attempt at my 'how many times I can say ©unt in half an hour' record.

It is very easy - a chimp could do it once the inner wheel arch is off

or alternatively leave the panel on there lift the car up a bit more and stick your hand in there you big girl if you want a really hard one to do try the E46 compacts.. they really really hurt

also just to clarify the light won't reset if the pad sensor has been worn through and not replaced

also if you do unplug the abs sensor do it with the ignition off otherwise the light should go off withing a few metres of normal driving

Thanks for this thread I am going to attempt it myself this week!

Maybe just taking the bumper off might have been easier? lol

Petkiller, thanks for the photos on how to access the rear brake wear sensor junction box behind the splash panel. I just replaced the rear rotors and pads on my '04 3.0i and your photos made the job simple and straightforward. Thanks.