The heater was working fine up until last week. Then it started blowing cold air. I messed with the buttons a bit and the heat came on again mysteriously. I added some antifreeze also. Now we're back to cold air again. Could it be the thermostat? If so; where is the thermostat located and is it difficult for the owner to replace by oneself?
Where is the thermostat located and is it difficult for the owner to replace one? on 2006 GMC Yukon XL Denali
by what your saying it sounds like the climate control head is at fault. You do have temp gauge in that auto it should be reading in the middle.
That is correct. Once the engine heats up the temp gauge reads almost smack dab in the middle. What is and where is the climate control head? I'm assuming that repair will be costly if it is that problem!