If your driving there is air flow which means its not your a/c fan. Now if the a/c temp isnt cool enough inside the car when you come to a stop then yes your a/c fan is bad or something stopping it from working.But this WILL NOT cause your car to overheat, but if the a/c compressor is about to lock up then yes it could.

If the car is running hot while the a/c is on but cool when its off. you need to check this

radiator stopped up or low on fluid, when the a/c is on it puts a strain on the motor.

Check for leaks, check an see if the radiator fan is working, do a coolant presure check too...


could be many things. but this is all a start not stating this will be the problem but a few ideas out there for ya.