Yukon Heater Works Intermittently

[StevoDevo]

Hi All,

I have a 2005 Yukon XL (with the dual climate control) and the heater has stopped working reliably. It seems that when starting the car from cold (when the system is set to Auto and 90 degrees) that it starts blowing the fan at full speed way before the engine is warm enough to blow out hot air. So it's blowing out really cold air.

Then after a while it will blow some really hot air and then it drops back to cold air, and then back to hot air. So it's really all over the show.

Any ideas on what to check to make it heat reliably?! It's cold out and i need the heat back badly!

Thanks!

Steve

 

[Wake]

If I remember correclty there is a temperature sensor inside the cabin to regulate the auto function.

In manual mode, does the heater work as it's supposed to?

All GM vehicles I've owned always put the fan at full speed on a cold engine when first started when in Auto mode. I guess it's to get you warmed up quickly when cold as soon as warmth is available. I never use the auto mode and just keep the fan turned down low until I see the coolant temp gauge move.

 

[StevoDevo]

Thanks so much for the ideas... you know what was wrong with it. I'm embarrassed to say the coolant level was super low and as soon as I topped that off I was back in business! Whoopsie! But glad I found this forum!!