2005 C230 Kompressor "glitch" question

The ambient temperature reading on the dash never reads what the actual temperature is. Some days it's -40, others it goes up/down right before me. I have changed out the probe, so that's not it.
Some days I get a message stating that my passenger side mirror signal lights aren't working, then some days they work.
Same as above with one of my license plate lights.
My question is, is there some type of "relay" that could be causing this??
Thank you for any help!!


