After I changed the pads to Carbotechs on my R56 MCS, I had no problem for a couple of thousand miles, then the brake warning and service light came on. Running the service/info scan, the car believes that the rear pads need replacing in 800 miles. I cannot get it to reset. Fronts, no problem. THe sensors are zip-tied out of the way, so no problem there. Why it thinks it needs new rears, and why it will not reset when I hold the b/c button in on the stalk, I don't know. Trying to clear the stored code, but it won't work. Any ideas? Thanks.
Fig

 

did you by chance ever figure this out? I'm having the same issue. But how do you know when it is the rear vs. the front sensor? by stalk do you mean the button on the top of the blinker stick? lol

 

Doesn't this mean that the rear sensors are in contact with metal? Did you install them in the pads?

 

I did another post on this and got a couple of answers under the ISSUES post. Not sure what is causing it, but it is def "bump related." THere is no way to use the sensors in the Carbotech pads, so you have a sensor on the left front and on right rear that has to be secured. I zip tied mine to the strut and to the upper rear control arm. WHen you go through the reset diagnostics, (see instructions in another post and print them and keep them in your glovebox ) and push the button on the end of the turnsignal stalk, it will show you that either the front pads or rear pads are the culprit and how many miles you have before they have to be replaced. THen just hold the button in for it to reset. But you have to go through the process to get into the diagnostics first.
It's gotten where when I go over a big bump, the warning BRAKE display would come on, but it wouldn't store a code, and would be off next time I started the car, which is good.
I changed to TSW springs on Mon, and tried to isolate the sensor more from other metals relating to suspension travel, and taped it up good on the exposed contact end. Bit I really do not believe that it was ever making contact with anything that would complete the circuit through the two wires to give an alert message. The contacts are recessed into a groove in the plastic housing. Based on my past experience, just as Robin says, as designed, it would not alert on the car until the brake pad thickness was worn down enough that the plastic would also wear away and complete the circuit thorugh the rotor. That doesn't necessarily agree with one of the other replies on the other post. I'll see if it is better in the next couple of weeks and will come back to this post.
Cheers!
Fig

 

So you twisted the two wires together before you taped them off right?

 

No, all you have to do is move the wire/sensor assy, just as it came out of the stock pads, out of the way. If you were to cut and join the wires, that would complete the circuit (same as wearing down through the sensor) and set off the warning that the pads need to be replaced.

 

Nevermind I see you have the sensor still attached.Just cut the sensor off,twist the two wires together and tape it off and the OBC should let you reset.Those sensors are around 30 bucks and are an easy snap in replacement.