I have a 2007 Impala LTZ, when it is hot outside the outside Temp gauge shows -38 degrees and the AC won't work, as I drive the car and the temp gauge, usually about 5 miles the temp starts to come up and then once it is above 50 degrees the AC will work.

Any Ideas?

 

since its a 07- take it back to dealer.
but the sensor in front of the radiator is bad. prob about $20.

 

you may even be able to easily replace the sensor.
on trailblazers- its easily acccesible in the front of the grill.
on the TB with digital AC... theres a 3 key combo that resets the sensor and many times it works again. if it doesnt- then the sensor is bad...

 

Thanks for the quick response.

 

what are the three bottens you press auto front and rear def right all together