i have 2013 c300
when in reverse the passanger exterior mirror does not tilt
followed all instructions from the manual
what can i do?

Are u sure the last button you pressed was the far right one(the passanger mirror adjustment one) before you engage the reverse?

^ What he says.

I had the same issue. Took a couple of times for this function to work. My independent MB mechanic said for some reason the c class does not seem to want to learn this the first couple of times. It works now and has been functioning as it should.

yes i have that button selected.

what did you do in order for it to start working?

Try this, start car and put in reverse gear, adjust mirror down to where you want it and then use the memory setting for your seats to confirm. Put the car in park and try it out...this worked for me.