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2021 Yukon Heat Cutting Off

Katy Sanders
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Katy Sanders New Member

Katy Sanders

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I purchased my 2021 Yukon AT4 brand new in June. I haven't had to use the heat until recently (I live in TN). The front heat blows warm air while I'm driving, but when I stop at a long light or put it in park, the air starts to blow cold until I start driving it around again. Also, in the rear of the cabin, it's never blown hot air...ever. Even after running the controls on full blast on HI for an hour -- air is still ice cold. I've tried it with the Auto Stop On and Off and it makes no difference. Anyone else have this issue? 

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