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2012 E550 Cabriolet 2011 VW Eos 1985 Pininfarina Spider
Brake Replacement
I have a 2012 cab and was wondering if the car has a front and rear brake wear sensor? Also, I read somewhere the rear pads can be replaced the first time without replacing the rotors. I have never heard this before. Is this true?
IIRC each wheel has one sensor installed in the brake pads, (usually the piston side of the caliper), but it might be only one sensor per axle. Easy to discover by pulling a wheel and looking at the caliper: If there's a wire coming out of the pad, that's a sensor. They're about $2 each so no biggie if there's more than one per axle.
Regarding the rotors, if they're in good shape (not gouged, still flat and round, within tolerance of runout and thickness) there's no reason not to just touch them with sandpaper and use 'em again. Again, disassembly will tell the tale. That said, common practice on these cars is to just do it right with fresh rotors and pads. Clean the calipers and especially the sliding pins really well, properly lube the proper places, reassemble, properly bed the pads, done.
"the cheapest part on a Mercedes is the nut between the steering wheel and driver's seat"
or
"there's nothing cheap about an old mercedes"
Last edited by rapidoxidation; Feb 21, 2026 at 08:35 PM.
I can't say a 100% confidence for your cabriolet version which is a C class chassis, but 4 door W212 of mine , facelift,
has brake wear sensor only on one side of the rear and one side of the front brake pad.
However these are so cheap and important, I believe your cabrio must have such sensors installed too by MB.
The rear brake pad wear sensor is on the right rear brake pad. At 1 pad only.
The front brake pad wear sensor is also on the right front brake pad. At 1 pad only.
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Both front and rear brake pad wear sensors been replaced, due to its wire coating looking bad. MB genuine.
Last year, I replaced again the rear brake pad wear sensor because I was doing-undoing the rear brake wear sensor so often due to parking brake and rotor replacement work/tuning.
This time I use knocked of MB parts...LOL. Work fine, because it was such a simple device, only copper trace, that is all.
I have a 2012 cab and was wondering if the car has a front and rear brake wear sensor? Also, I read somewhere the rear pads can be replaced the first time without replacing the rotors. I have never heard this before. Is this true?
FRONT vs. REAR:
The rear pads hardly do anywork with original setup.
So you may have a chance early-on that your rear rotors may be reusable as-is or machined...
The front rotors are SOFT and get spent easily by HARD factory semi-metalic pads to stop a heavy car.
Both front [pads + rotors] are worned down together until you consider a different setup (ceramic pads by Akebono: Japanese grade!). Then brakes work with hardly any dust or wear... go figure how ceramic compound work.
SENSORS:
Pad sensors are located on passenger side, 1 per axle only - The skinny pad is the inner pad with the piston. The outer pad hardly wears due to caliper springs preventing calipers from sliding over lubed pins.
RELIABLE:
At higher speeds, strong brakes require non-warped true rotors. When in doubt: replace all 4 rotors + pads - Your life depends on stopping power!
COMPREHENSIVE DETAILS:
Effective brakes rely on more than pads and rotors :
tire pressure
silicon lubed sliders
vacuum booster (check valve /blow-by)
wheel alignment
buble-free clean rear brake lines
decent control arm busings
wheel bearings minimal freeplay
Inspect & report with pics as needed - You can look at the rotors to see how front brakes are working evenly well or not for long trouble-free service life.
Last edited by CaliBenzDriver; Feb 22, 2026 at 02:15 AM.
The rear brake system, the caliper, if yours is like mine with plastic piston, you best replace the piston and also the piston seal + dust seal using Brembo Kit
Replace the rear rotor too and you get new good surface for the PARKING BRAKE and CALIPER BRAKE.
Even my brake hoses are new, all 4.
So basically all of my rear and front brake system have been totally properly rebuilt and all 4 now uses new rotor disc.
if you decide to reuse the sensors, take care to save the tiny metal clips sandwiched between pad slot and sensor. when the sensors are replaced, it's the type of part one should save for next time.
if the rotors are within the proper tolerance for thickness and if true and not warped you can reuse them. I did it on my wagon, when I replaced the pads last time.
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