I have a 2003 S500 4matic and the brake notice went on on the dash and i want to DIY. I have several questions and hope someone can steer me correctly:

1. Is it possible tell which brake pads need replacement (front or back) without removing the wheels and doing a visual inspection? There is no squeaking or grinding from any wheel and the front pads have approx. 1/8" of pad left.

2. If its the fronts, do this car have 1 or 2 sensors? How many in the back?

3. Does anyone have easy step by step instructions on replacing the pads? I have checked other forums and none of the videos show the front caliper that looks like my front ones. They all have 2 pins but I see no 2 pins to punch out on the calipers on my car.

3. Does anyone know of any video that shows the procedure?

4. Are there any special tools I will need and, if so, which ones and for what?

Any suggestions/ideas/instructions/warnings/advice is greatly appreciated.

I am somewhat mechanically inclined and have changed pads in other vehicles but do not want to take a risk on this car unless I know exactly what I'm doing.

Thanks in advance