If it has any wear, they will also replace the brake pad wear sensor. That sensor rubs against the rotor when the break pads reach minimum thickness, thereby completing a circuit which alerts u to the fact the pads must be changed asap. Once it wears/rubs like that, it can't be reused
The rear sensor is #12 in this diagram. There is one sensor for the front brakes and one for the rear
Last edited by gfeiner; 02-04-2013 at 08:43 AM.