I belong to a few other Chevy sites so I decided to join this one too. I have a common problem on the 2001 Impalas, but can't find a true answer anywhere. While driving down the freeway today with the A/C on it all of a sudden got warm and felt like the compressor went off. When I got to where I was going I left the A/C on, but the compressor wasn't running. After turning the car off the cooling fans ran for 5 minutes. One odd thing is that the driver side fan was running strong, but the passenger side fan was barely turning and eventually stopped. When I started the car back up the fans came right on from the begging even thought the engine had cooled down. I have no reading for temp on the dash either. I see a lot of people have had this problem, but no one posts a solution on any of the sites. They say replace the thermostat and coolant temp sensor, and clear the computer battery, but everyone that has done it says the fix only lasts a week. Any help would be appreciated.

 

So I replaced the coolant temperature sensor and it worked until today. Someone warned me that it would only work for a week. Now all my problems are back again. Same exact issues I had before. I have no idea what to do next. I have read hundreds of posts on other sites with the same problem, but no one has any clear answer on how they fixed this problem. I've put more money into this car in the 2 months I've owned it than all of my other vehicles including work trucks in the last 2 1/2 years. Trans at 58,000, AC Compressor, Brake lines, Seized calipers, MAF sensor, and many other smaller fixes.

 

Could be the contacts are welded together. I'd suggest checking the relay coil voltage if not present, unplug the relay, and that will be your culprit.

 

Sorry I forgot to mention I did swap the relay and that didn't work. When I pulled 1 and 2 the fans went off. When I pulled 3, they kept going. I haven't pulled up wiring diagrams yet to see what relay does what. Thanks for your help!

 

Ok, so the A/C relay works. The Fans works. Does the compressor work? I mean do you see the compressor engage? Is it on when the AC button is depressed? This is going to lead you to where you should be looking.

 

AC Compressor shuts off when it starts acting up. I'm thinking the computer thinks it is overheating and is shutting the AC off. When I got everything to reset after changing the coolant temp sensor, the AC went back to normal.