So here is another crazy one for you! I also have an 08 LT, on occasion my temp. gauge does not register temp. when this happens my A/C does not work, during warm weather it may or may not register so my a/c may or may not work, during the hot weather, it will usually register if not right away shortly after running and when it does my a/c will work. I don't understand there being any correlation between the two. any ideas?

 

if the ac system ran in cold temp the evaporator would freeze...so it has an inhibit temp...below that temp it won't work....and the data is from the ambient temp sensor.