My A/C finally works (2012 model)

[Camaromann]

Re: 2012 AC
To repeat my problem: The A/C was inconsistent and going from cold to warm to cold - on a repeated cycle. No strange smells, no clicking noises, and the compressor did not appear to be cycling on and off.

With 100 miles on it, 2 weeks ago, the dealer reprogrammed the car's computer. It did not help.

Today, with 550 miles on it, I took it back to the dealer.

Okay....after five hours at the local dealer, the A/C is finally working like it should. (SO FAR)

First, the mechanic removed all of the 134a from the system and checked the content. He found that there was 2 ounces of freon TOO MUCH. The system is supposed to have .54kg (approx. 19 ounces) and my car had .61kg (approx. 21 ounces).

Then, he called GM to check if there was anything in their database relating to A/C issues for 2012, and asked them if having 2 extra ounces of 134a would effect the system's performance. Nothing to report from GM.

Then he refilled the system with the proper amount of 134a, and then hooked up a laptop computer to recalibrate the actuators for the internal dampening doors. Finally, he checked the A/C system control board.

We went drove for a 3 mile test drive in 95 degree weather, and the A/C was (finally) ice cold. More importantly, it stayed cold and did not cycle cold/warm/cold like before.

The mechanic thinks that the extra freon might have caused higher operating pressure, which might cuase the compressor to cycle too frequently. But, only 2 extra ounces - he discounted that as a reason for the problem. He did conclude that the recalibrating of the actuators for the dampening doors is most likely the reason for my issues. He explained that these doors open and close (to blend the cold air with heated air to acheive the desired temperature) based on an electrical voltage variations. He explained that the compressor is always working like it should, but that it is most likely that I was getting warm air blending intermittantly with cold air.

Problem solved. SO FAR. I have driven my car another 35 miles during intense afternoon heat & humidity, and all appears to work well.

[BowtieBelle]

Glad you got this resolved!

[OPP]

Looks like your car missed the quality control deal.

[mike25]

i feel better now that my car sat in qc for so long..there was rumor of an ac problem..and i think this confirms it.

[SS_Matt]

Originally Posted by mike25

i feel better now that my car sat in qc for so long..there was rumor of an ac problem..and i think this confirms it.

Mine was in QC for about 2 weeks, so if that is why, and they resolved it- cool.

[rydahog]

what dealer in fla..sounds like the tech did a through question and answer diagnosis, good to hear..for change.

[Camaromann]

Originally Posted by rydahog

what dealer in fla..sounds like the tech did a through question and answer diagnosis, good to hear..for change.

I take my Chevys to GRAND PRIZE in Southwest Miami. The service writer (Bill Hamilton) is the most experienced Chevy service man in Miami, having worked at DON ALLEN Chevrolet since the 1960's. The mechanic (Don Murray) who also worked at DON ALLEN since the 1960's. This mechanic is the finest Corvette tech in the business. He has seen it all.
He did a great job correcting my A/C problem, using his "old world" experience and modern computer technology to his advamtage.

[LiveStrong]

You would be surprised at the issues of how slight of an overcharge on an A/C unit can cause. Too much freon is just as bad as low freon.