2003 GMC Yukon remote reprogram / frt pass ac vents always hot

[PapaBobby]

I just purchase a 2003 GMC Yukon and I can't get either of the remotes to work. I changed the batteries, but that didn't help. Also, when I test drove the vehicle the frt passenger vents ( Auto air rt/lt) would only deliver hot air even though the temp was set to 60'. Any ideas would be greatly appreciated?

[newdude]

Does the AC system have a good refrigerant charge? Can you hear the temperature door motors run when you change temperature? If the door actuators run fine, I'd have the system charged and tested for leaks. Rear lines are a common leak point on those trucks.

[PapaBobby]

The driver's side vents and rear air is emitting cold air. The two frt passenger vents only blow hot. I was considering replacing the dash control unit as an elimination repair.