Pontiac Repair: Pontiac HVAC, pontiac bonneville, fuse block

Question
QUESTION: Own a 2001 Pontiac Bonneville SSEI.  The air conditioning would stop blowing cold air intermittently (maybe once every 3 months) and that would only last a day or so.  It has been out for a week.  Any ideas what I can check and where to find it?  Its a  3.8L V6

ANSWER: Hey Bob:
weel it can be a few things. The system can be low on a charge and causing the issue. Or it can have an electrical fault of some kind that is not allowing the a/c compressor to run. When it was working was the system good and cold or just cool? That is a tip off. If it was good and cold and intermittaantly quit then it has to be an electrical fault if it was cool and the nquit I would lean towards it being low on a charge. turn the car on turn on the a/c to full cold and take a look at the A/C comprssor it on the very bottom of the engine near the radiator see if the very front of the cpmpressor is turning not just the pulley. if it's not running the ntake a look in the under hood fuse block for any fuse labled a/c or hvac something like that and see if it's blown. If not look for the relay labled a/c or compressor and swap it with another relay that has the same part # stamped on the top of it and see if it starts to run. That is where I wluld start looking. Good luck :)


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QUESTION: Hey Todd, when the a/c works, it'll freeze you out.  Checked both relays in the fuse block (A/C clu and hvac sol), bot are good.  Compressor is not engaging. Where to next?

Answer
Okay 2 other things to check have someone sit in the car and turn the a/c on and off and put you finger on top of the a/c relay in the fuse box and see if you feel it "click" on and off if it does then chances are it's from there out to the compressore that your loosing the compressor control. If not then the engine computer for some reason is not turning the relay on and off. If it does click then use a 12 volt test light at the compressor. unplug the clutch wiring and use jumper wires from the terminals in the connector to the test light start the car up and turn the a/c on the light should light bright. if it does the clutch is bad in on the compressor. If the relay doesn't click your stuck. You need a true scan tool to see if indeed the engine compouter is #1 getting the request from the HVAC control head Via the insterment panel module and #2 if it's getting the request is it sending the signal to the relay to turn it on. It' a complex system and with out a scan tool your stuck.