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AC and cooling fans failures in Houston!


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I have a '09 Pontiac G8 w/ 3.6 alloytec V6 automatic. It has nearly 185,000 miles and no trouble codes when I checked w/ Blue Diver scanner.  I do have to replace the blower motor, since it has been making some noise.

On 7/30, I started my car to drive home and the AC was not cooling.   I cycled the AC off & on with no luck.  Once I was home, opened the hood and noticed both cooling fans were not running and my car's temp gauge was near 200F.  Again I cycled the AC and there was a slight engine tone change but neither the fans or the AC were running/working.  Might have been current draw from the dying blower motor when the engine tone made a slight change. 

I checked all the fuses and relays associated w/ the fans and the AC, found on problem.   I disconnected the cooling fans and connected a 9V with test lead clips and the fans would spin.  So, no power to the fans.

Jacked the car up and checked the AC compressor power connector and no power there.  Once again I used the 9V and leads to check the compressor clutch and I could hear it click everytime I applied power to it.  No power to the AC compressor.

I don't know what else to try.  Checked on G8 forums and no one had the same combo of problems at the same time.  Maybe it's the low pressure sensor on the AC?  I was a little bit low on coolant, so I added to the cool line.

Down to taking it into the dealership or local shop for repairs.  Disappointing 😞. 

2 Answers

Check the fan control module and the temperature sensor.

Posted by: @jktodd69

I was a little bit low on coolant, so I added to the cool line.

I don't know quite what you mean by this. By "coolant" do you mean refrigerant? By "the cool line" do you mean the low side R134a port? If so, how do you know it was a bit low? How did you add more, and how did you know how much to add? What are your high and low system pressures?