A/C Freezing Up

[Beartoothweb]

I've had this issue for a long time now, but we live in Montana, so it's usually not too big of a deal. But, I just made the 2500 mile drive to Florida, and of course, it would be nice to address it.

My A/C condenser is freezing up. If I run the AC on HIGH, it won't freeze, and all works well, but once it does freeze, there's almost no cooling, it sounds like the fan is broken behind the dash, and no air comes out.

I 100% know it's the freezing issue as it only happens after the AC is on low for a while, and the condenser is visibly covered in ice. It also melts all over the garage floor. The rear AC works more or less, which is strange, but that's how we keep from boiling on the long trips.

A while ago, I replaced the pressure sensor from rock auto, but it didn't fix it. I'm at a loss for what to do now. It doesn't appear to be overcharged.

Any ideas on how to diagnose and/or fix it?

Thanks!

KD

 

[DirtyBlackHoe]

What year is your vehicle?

 

[Beartoothweb]

Oops, 2007 Yukon XL denali

 

[DirtyBlackHoe]

On my wife's 2007 Suburban, when we the factory AC controls were swapped out, they installed a different part number and it has to be re calibrated. Mine did the same thing as yours until I had it reprogrammed.

Does your "rear air" button say AUX or REAR in the upper right hand corner?

 

[Beartoothweb]

Mine says "rear". I swapped out the original controls when I got the rig because the original + and - buttons were all worn out. I wonder if that had anything to do with it. Do you just take it to the dealership to reprogram it, and what do you tell them to do?

Thanks!

 

[DirtyBlackHoe]

I had to pay a $65 reprogramming fee on mine. Mine had the updated controls and when I bought it the lady said that it had an issue with doing exactly what you said. I talked to my buddy that is a tech at the dealership and he said bring it in to be programmed. Ever since then things have been perfectly fine (knock on wood).

I would just tell them that you need the AC controls reprogrammed.

I would bet that it is from swapping the controls and not having them programmed.

 

[Beartoothweb]

Thanks! I'll give it a try while I'm down here.