Hello!
I'm pretty new to the site but truly appreciate that this forum is available, as I have been able to do several repairs and maintenance on my own. However, I've recently put new coolant into my vehicle and although it's only happened a few times, the exterior temp will change to a minus (-) degrees and the air will begin to run warmer.Is my thermostat going out or what?

Thanks to allwho respond!

 

checkout trailvoy.com

theres a few threads there with pics on how to replace. its a $20 part.
the thermostat and engine temp sensor are separate from the ext temp sensor.

 

ex sensor ac driver side mounted front of grill under black plastic rad plate

 

2003 trailblazer also haveing a problem with a/c turning off ext temp tells me its -31 outside so a/c stops would this be a ext temp sensor