A local shop here in NYC was repainting my rear bumper of my 18 C63S and now the trunk 'foot kick' sensor seems to have stopped working. For the life of them, they could not figure out what got unplugged/disconnected. The keyfob button still opens the trunk though. I'm a second owner so my warranty does not work here in the USA. Any ideas?

 

remove the diffuser and check the sensor itself, Either the wires connected to the sensor; (a big bar that runs across) is disconnected ot the sensor is misplaced

 

Guarantee you the sensor was misplaced or disconnected. It happened to one of the other guy's on this forum (forgot the thread).

 

Try restarting the process again: Turn power on (I'm not sure if this is required, but won't hurt) Hold the button down that's in the driver door. At the same time, hold down the trunk button on the FOB. Turn off the ignition. Go around back with the key in your pocket and try again. I found this in the fine print of the owner's manual yesterday. Had the car for a few weeks trying to figure out why it didn't work. A 'duh' moment...

 

Your trunk foot sensor once worked?!?

 

Not sure who you're asking. For me, it never did. I apparently had to 'turn it on'.