Took my 2011 HHR to the dealer today for an oil change. After picking it up the AC worked fine for a couple miles then stopped blow cold air. When I turn on the AC there is no longer an increase in RPM like there was before the oil change. It's just blowing outside air into the cabin. Could there be a blown fuse? "sudden but unrelated" loss of freon? The AC was fine on the way to the dealer and always has been. This is the second time in a row with an oil change from this dealer that has resulted in supposedly unrelated issues.

 

First thing, make sure the belt is in place and functioning in good order. If it's broken, the battery can't charge, and you'll get stranded.

Then check all relevant fuses. These are the free and easy checks.

 

Any chance the Check Engine Light is on ? Certain CEL codes will disable the AC compressor.

 

Yes, a CEL code like P0128, will do what FMG posted, pop off that fuse box lid and look for loose fuses or relays

 

No CEL at this time. I will check on everyone's suggestions. With "check the belt is in place" you mean the serpentine, right?

 

Correct, check to ensure it’s there.

 

Serpentine belt is fine and all fuses, breakers, and diode appear fine too. I notice the idle does jump up slightly when turning on the air, then drops back to normal rpm.

 

Have a look at the MAF sensor connector, see if it’s plugged in firmly


That’s it in the plastic tube towards the air filter box, and yes the elbow should be connected to that tube, it’s a stock photo with the tube disconnected for visibility

 

I reseated the MAF sensor but still no go. Could I just need to add refrigerant?

 

Kits are available for that at the parts palaces, look for any leaks in the AC lines and connections first.