Climate guru's I require assistance 02 MGM cabin too cold

[SpartaPerformance]

I have a customer with an 02 MGM that states after driving for 45min or so the cabin gets frigid cold with a/c on no matter what the temperature is set to. It has auto climate control, she has taken to other mechanics and dealerships and they can figure it out. She doesn't have copies of her service reciepts so I can see what they've done or looked at. I'm hoping somebody here has had a similar issue and give me a good starting point. Thanks

[RoyLPita]

Blend door actuator?
Thermostat?
EATC head?
A/C cycling switch?

[fastblackmerc]

Blend door actuator?
Thermostat?
EATC head?
A/C cycling switch?

I'd go with the blend door first.

[Granddaddy Marq]

Is the fan ajusting automaticly. High to low, low to high? That could be a clue on where to start looking.

[Gryphonzus]

If nothing else you can swap out your EATC module with theirs and see if that fixes the problem. Then you will at least have eliminated one unit.

[EMAS]

I'd look at the temp sensor system first. It is the only single part failure that would explain the problem. If the blend door failed the fan should still turn way down if not off. If the fan was some how stuck on too high then the blend door should warm up the air it is putting out. I'd suspect the duct to it is blocked or maybe there is a significant build up of crud on the sensor is insulating it, or it could just be a bad sensor.

[Granddaddy Marq]

What ever happend here. Did you figure it out. Curiousity is KILLEN' ME!