I received a wheel speed sensor trip [right rear] where everything goes yellow on the dash.. So I pulled the sensor out and went to see if I could clean up the reluctor ring but I can't turn my rotor... then turned it on and put it in N in case that mattered.. didn't.
While I was troubleshooting why I couldn't turn my rotor I came across some "set the car in brake pad change mode" info, but when I got to that menu it didn't have the option, and my EPB on the DiagLink said not applicable so I eventually went to check if the pads were touching the rotor..
Yes, pads touching rotor.. so I was able to push back the outer pad but the inner pad is not moving at all.
Not sure if I need to pull off the caliper next or am I missing some other reason why it wouldn't move?

pad moves

inner pad stuck

outer moves, inner doesn't

 

Isn't there an EPB release lever on your vehicle?

 

no I have a foot/pull-handle setup

 

Sounds like a stuck piston. May need a rebuild.

 

I was able to move the inner pads a touch eventually and still didn't turn of course because I have to do ALL the steps like putting it in N again...
I'm good on the caliper/brakes thing, but now I can spin the wheel I think I could prolly scrape some schmutz off... however, AI tells me that the 65535 speed I'm reading from there will be unlikely to be crud on the reluctor and prolly something else - we'll see..

 

Wheel speed sensor trip? What exact fault codes do you have? With your scanner what are you seeing for live data on the sensors, is the right rear not working, is the speed different from the opposite side?

With those large lips on the rotors looks like they need to be replaced. The wear limit of most MB rotors is around 2mm. The pads in the photos look ok still but i'd replace while doing the rotors.

The pads will touch the rotors when not braking, they just wont be clamping down. Theres no mechanism that pulls the pads away from the rotors when taking your foot off the brake pedal. You should be able to spin the rotor by hand though, you may hear the pads rubbing the rotor but shouldnt be stuck. if I wash my car then dont drive it for a day or two the pads will seem stuck to the rotors and when 1st driving off ill hear them cracking loose from rust.

Trying to move the pads while the caliper is still installed will be hard. You will want to reach around to the back side of the caliper and pull it towards you, that will basically push the piston back into the caliper.

You are working on the right rear wheel? Do you have both rear wheels off the ground so the wheels can spin freely? Not sure which differential you have but in my W204 4matic for either the front or rear wheels to spin freely both front/rear wheels have to be off the ground.

In general I service the brakes every spring after winter. Basically just remove the wheel like you did and inspect everything for wear. Spray brake cleaner to clean off the brake dust, clean the contact points where the pads ride in the carriers. Looks like you have the nice AMG calipers which im not too familiar with. Though looking thru the 2015 E63 manual theres no mention of switching to change brake pad mode that is seen on later models. Doesnt look like you have electric parking brake. There will be an electric motor on the caliper if you did.

How does your brake fluid look? I replace the brake fluid every 2yrs per the manual. I noticed a color change with old brake fluid, will go from a gasoline color to a dark brown color over time. Also check the level, from the wear its probably nearing the low level. Dont fill it, just note the level.