2003 GMC Yukon A/C only blows when driving.

The fan isn't working or is gummed up. Take it to a shop. When you're driving fast, does it make a difference if you turn the air recycle button on or off? They should be able to fix it. My A/C makes a fairly loud clicking noise when it's very hot outside. One per second. The noise comes from the inside near or under the steering column. I'm thinking its a vent door trying to open/shut. It usually stops after about 10 minutes. Otherwise, the A/C itself works fine. I also have a 2003 Yukon STL 4WD

with R134A refrigerant, that is how it works best for whatever reason (when it is driving, not idling).

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Did you find an answer?? I’m having same issue for quite a long while now but never get to it. Fan works though. They told me to clean up the condenser. But haven’t tried.

Did you check the Blower motor or the resistor/module. You can also check cabin air filters, if you have never changed them you wouldn't believe how clogged they can get.

Shawn, I’ve checked both, module and blower motor. I’m trying clean the condenser see if it helps but don’t know quite how with out taking out, unless I ready need too....