Have a strange phenomenon going on, so wanted to see if anyone else is having an issue.
I have an 08 MCS, and changed to Carbotech pads after about 6K miles. Since they don't have provision for mounting the OEM sensors, I have them zip tied to the struts, F&R (one on each end.) They are out of the way where they cannot contact anything and just "ride along."
About 5 times now, I have had the service brake warning come on while driving. Each time, the car thinks that the rear brakes need to be replaced. Sometimes I get hte red "car on lift", other times I get the yellow one.
I reset the service indicator, and no problem for a couple of weeks, then it happens again. I have noted that this only occurs AFTER I have hit a large bump, like an expansion strip or road construction patch, etc. On Sunday, it happened again, right after a bump. When I went to get in the car about an hour after that outing, the warning was gone and no stored code on the tach display.
Anyone else having something like this happen? It's not serious, but it's a little annoying.
I can't believe that the unused sensor is shorting out and sending a signal to the ECU, since it normally does not do that until the sensor i worn down enough to then complete a circuit through the brake rotor. But something is making the car think the rear pads need to be replaced when a bump occurs.
Cheers!
Fig

 

Hi Fig,

I'm not certain but I believe that the brake pad sensors work via proximity to a ferrous metal. When you hit a bump, they are probably jiggling close to the shock/strut and tripping themselves. If I were you, I would try wrapping them with a dense foam and then zip tie them in a position where they will stay away from metal objects.

 

My light began to come on in one specific place oin my way to wor...uphill on a left turn. Turns out my brake fluid level had gone down over-time sufficiently to turn on the light on that uphill turn. Maybe that's the problem.

 

The sensor has a small wire going through it, the light is then tripped when this wire is severed, the issue with the symbol of the car on the lift usually means you have a bad sensor, or it is unplugged, try unplugging it and plug it back in, if that doesn't work, you may have to replace it.

 

Same thing here, after topping off the brake fluid no more lights.