Would a magnet have anything to do with the Temp and direction to stop working on a 2005 GMC sierra ? Installed a Garmin 55 dash cam with garmin magnetic mount and my compass and temperature I think quit working, lights up but can not make out readings all scrambled.I Have sent to a company that does nothing but circuit boards, and they said it worked fine when they plugged it in. any one have any answers to this?

Where did it mount?

Try taking the Garmin out and see if it works. I can see how it would effect the compass, but not the temperature.

Right behind the mirror Talked to repair said they found some solider cracks even though it worked before they took it apart.When I get it back on Monday I will plug it in and if it work okay if not will take magnie off windsheild and try that if still does not work buy new truck. Just kidden

Did still did not work Thanks

Okay so the Garmin is out and the issue remains?

Sent the mirror to *. C. tested OK on arrival I told them to look inside found some cracked welds on board repaired and still worked good,on its way back to me will plug in when it gets here and it it does not work will take mount off windsheild and retest if that fails not sure whats left.

Okay, makes sense now. Looking forward to hearing what happens!

Okay got the mirror back from * C plugged it in and worked great until I put Garmin 55 dash cam back on windshield turned key off and back on and was just like it was when i sent it to SC. took camera back off cycled key came back on works great So I guess I AM going to have to use suction cup for mounting witch Garmin sent me free for this unit just in case that was the problem. All I have to do now is re calibrate and will be back in business. For some reason I thought I had removed the camera when testing ,i guess iI did not

Any One know how to calibrate a compass on a 2005 GMC Sierra?