Be sure you are removing the caliper mounting bolts from the backing plate, not the bolts securing the caliper halves.
You need to take the pressure off the pads by prying the pads away from the rotor so you can remove them and/or the caliper.
My experience with the brakes on the C-Class are that they wear the rotors quite a bit, making it necessary to either have the rotors surfaced at an auto parts store, or replacing them with new. If you are lucky, they aren't so bad that they can be surfaced. I think the limit is.100 that can be taken off.
If you waited unitil the warning came up on the instrument panel, then you will for sure need to replace the sensor that goes into the brake pads. Don't try and re use the old one, as it will continue to give you a warning message.
Check to be sure the pads you buy have the hole drilled in them for the sensor. If not, you can carefully drill a hole using the old brake pads as a guide.
Tuesday, November 27th, 2007 AT 1:58 PM