Where is the AC low pressure valve on a 2005 GMC Yukon Denali XL? Compressor cycling on and off; warm air, want to add Freon.

Chech your ac fan clutch, may need to add freon to to your ac system

three things 1. low on freon, 2. ac relay, 3. fuse, and last the clutch on front of the ac compressor.

Not on the same type of vehicle but I remember that I had the same problem and when I got it analyzed, I've been told it was the compressor clutch that was gone. Nothing to do with pressure or freon in the system!!!

Does the front blow cold ? Diagnosing rear problems
Taking to a qualified repair shop an having it diagnosed would be your best bet >

The compressor on the air conditioner in my 2000 GMC Yukon XL went out last summer. Had it and the whole line replaced at a local air conditioning shop last fall. Used it little before cold weather. Warm weather this spring and no cold air. We could hear the compressor trying to kick in. The shop told us that the control console was bad and had to be replaced. They told us the part was on back order and did not know if they would be abel to get one any time soon. We took the Yukon into the local GM dealership. They told us that the high side fitting was bad and that the freon was very low and that they would have to deal with that first to check the system. Called back to the air conditioning shop and they said they had a console come in and they would put it in and check the high side fitting. I now have cold air and questions. Bought Yukon in 2005 used, had always had problem of not switching to cold air once the heater has been used. We were told changing the console should fix that. It has not changed. I feel like the console angle was a scam, that the system was just low on freon. Each shop was blaming the other for trying to scam me. And what can fix the heat to cold issue? If anyone has answers I would sure appreciate the knowledge.

ac on a 2005 gmc yukon not blowing and cant here compressor the rear ac of the truck is working fine, are there any fuses i can check?

add freon it is low

bigger hose is usually low side.

have the low side pressure cycling switch tested.

Your system has R-134 Freon in it. the 134 is made up of smaller molecules than the old R-12. The R -134 permeates through the rubber parts of the system. If the system gets too low on Freon, the compressor will stop coming on.(low pressure cut out switch). Have the system serviced with an A.C. machine that can vacuum, measure the amount of Freon in the system, and add the right amount. The machine can also inject die. Later the die will show up under a black light.This will show any leaks you may have.