i took my car to a stero shop because my cd changer stopped working, so i had them install an aftermarket cd player and when i got it back the A/C was not working and they told me it just had to reset itself after driving it for a little while. How can i fix this now, its really hot here Iam at, thank you, to anyone that can help.

 

what does not work? as in u cannot control the fan speed? the temperature? nothing lights up? what? it could be something like a un plugged harness to cut wires.