I've got a 2005 Supercharged SS Monte....she's pretty great. The only major work I've had to do so far is replace the dash because of some bad motors in the gauges and replace a transmission line. Not too bad. My question is, the overhead display (mine has options from on-star that do everything from turn on house lights to open garage doors etc) When the Direction and Temperature are displayed, the temperature (outside) is WAY off.. so far off it is almost as if I could take the displayed temp, and minus it from 100 to get the actual temp. haha.. not cool. I'm in VA right now, the summer is an average 100 degrees a day. Why does my readout say it's 13 degrees outside? Anyone had these issues before? Praying it's not what I think it is, or a PCM .. something horribly expensive.

Please give me your thoughts. Thanks to all who reply.
**PS my Monte just broke 67000 miles today***

 

When the Direction and Temperature are displayed, the temperature (outside) is WAY off..


Sorry I don't have a solution for you but I want to join you in asking for help because I have the same problem. I live in Florida and its always off in the summer months by 20-30 sometimes 50 degrees. in the winter it seems to be close to accurate though. What the H right? I figure I will probably have to buy the whole "assembly" and I'm just not down to spend that kind of money to know what the outside air temperature is when all I need to know is built into my common sense......it's so hot I can hardly breathe!
All the rest of the functions work properly.
Have a problem with my rearview mirror too. The "Auto" adjustment for night time driving is only working on half of the mirror now so it's two tone, and it's stuck that way. Silver on the top, amber on the bottom.

 

To the incorrect reading. You probably have to change the Ambient Temperature Sensor in the car.

To the Mirror. You need to replace the mirror, there is a fluid in the mirror that evaporated and can no longer change to black.

 

Thanks for the thought. I will look into the part at auto zone this weekend and install it. Hopefully if fixes the issue.
https://www.napaonline.com/Catalog/C...+50012+2012040

AC ambient temp sensor? thats all i found online with a quick napa search...