crash2646

I began to have the dreaded squeaking brakes [metal squeaking/Grind, not little mouse squeaking]... so i took the car into a local BMW dealership. They would not take the car in for service because the computer said the brakes didnt need to be serviced. I told them that there was also some pulsing and that the driver thinks the brakes need service screw what the computer says. So i was able to get them to take the car for a test drive... The "shop Foreman" drove my car and returned telling me that i am too picky and the brakes are perfectly fine. (at this time there were no visual blemishes on the rotor) well 500 miles later the pulsing got worse and now i have a very distinct grove mid-rotor [Driver Front]. I took it back and needless to say the dealership told me i need to have the brakes serviced....OK well, conviently i was now 300mi over my warranty... fts!

So besides the dealership being cheap. what is the purpose of this so called wear sensor? IF it is indicating that my brakes are fine AND grinding the rotor at the same time... any suggestions? PLUS isnt there only one wear sensor, and it happens to be on the Driver Front [Damaged Rotor]? Pictures below...

Should i go ahead and replace the front brakes, even tho the computer says they have 6k miles left? Do you think this groove can be ground out?

Currently @ 51k mi

mrfva

If it was noted in your records that you complained about the brakes initially
(just before the warranty expired), a good dealership should address your
your problem under warranty, especially being only 300 miles over.

I had a steering column replaced (pro bono) when I was 1k+ miles over warranty.

bespoke1

They should address this issue out of warranty. No exceptions. I had a similar issue with my car. You have service records indicating that the problem was checked and not repaired properly.......... Contact BMW NA. They will resolve this.

Dealers pulling bullshit like this are the only reason I wouldn't buy another BMW....

Go get 'em!!!!!

B

P.S. I had all new brakes and an AC compressor replaced out of warranty.... For nothing.

bbrase

How does the electronic sensor work, does it start dragging/rubbing/wear away like old fashion brake wear sensor? Does the end wear out/off to trip the sensor. I know your suppose to replace the sensor when you replace the brakes, but if the sensor hasn't gone off/worn is it still good?

bespoke1

I'm not 100% but I think as the pad wears the sensor starts touch the rotor. Hopefully others will chime in but that grove in the rotor shouldn't happen anyway, not even with the sensor touching. What they did was misdiagnose the problem. Not all techs in dealerships actually know what the F they're doing by the way. Some are downright awful.......As you well know.

advancedlogic

Exactly. A thin piece of copper wire encased in a rotor-safe compound keeps the circuit closed. As the brakes pad depth decreases, the sensor begins contacting the rotor. This friction wears out the compund and exposes the wire. Continued friction breaks the wire and trips the light. This should happen before rotor damage occurs from worn brakes. Technically the sensor is still good if this hasn't happened, but the material becomes brittle with age. Attempting to remove the sensor when changing the brakes will usually destroy it. The sensor circuit on the OP's car may have been faulty or the sensor may have become dislodged from its designated position on the pad, as it failed to illuminate the lamp and set the warning. I would use a heat-resistant silicone compound on the sensor to ensure it remains in place.

pinguhk

dont trust the computer.
best to look at it every 6 months to see how much you got left.
I only used about 5% of my ebc green stuff and installed it for 10 months now and done about 8000km

turboawd

that groove and possibly the squeek was probably caused by debris. your pads probably had life left in them, so that might be why the dealer said its ok.

the sensor is 2 wires connected together in a loop. when the sensor wears down, the wire wears through and the circuit is open, which triggers the warning light.