mips

Friends brake warning light came on recently and the pads have about 4-5mm of material left on the front from what I could see through the wheels.

Do the pistons in the callipers require a special tool to turn them in like some modern cars do? I'm use to just slowly applying pressure to the piston in order to push it back into the calliper.

Do the sensors have to be changed with the pads or can the old ones be reused? How many are there? How do these sensors work, are there conductors inside the pads that get exposed when they wear down?

Is it a simple case of just undoing 1 bolt on the calliper and lifting it up out of the way?

Assuming normal use of 'copper slip' on back of pads to prevent any squeel/noise is still required?

I'm assuming I don't need to bleed the brake lines as I'm not opening them up? I'm gonna tell her to get the entire system flushed with the next big service.

Anyone got a nice picture guide to follow for the procedure?

I've done brake pads & rotors on plenty of cars (never a merc though) and just wondering if there are some special things I should keep in mind when doing it on a merc. I've looked on the net but not sure how much things vary between the different models & years.

Any assistance would be greatly appreciated.