Hi-

I have an '07 997TT and am getting no cold air at all when the a/c is on. Gauges show about 95 psi on both sides when it's on (basically the same as when it's off). My Autel code reader shows no faults, everything seems normal.

Any guidance on how to verify that the compressor is bad? Or how to check the pressure switch(es)?

Thanks,

Chris.

 

An easy first test would be checking the cooling fans. With the engine warmed up turn on the AC. When the AC is switched on the cooling fans should turn on and keep running. If this happens this is a good indication that the car is "trying" to run the AC. If the cooling fans do not turn on this is a good indication that the car has detected a fault in the system (common things include high pressure cutoff, low pressure cutoff, temp sensor problems, bad AC switch) and is not allowing it to turn on. If the car is not allowing the AC to turn on you need to scan the HVAC module for faults.

In my experience with AC these are the most common issues by far:
1- Improper charge level - either due to a leak or using a DIY recharge kit
2- Bad AC control solenoid
3- Bad AC compressor

 

Late follow-up on this...
It was a low charge level and user error on the gauges that was the problem. Thanks for the great info.

Chris.