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2004 GMC Yukon Denali Question: the air or heat only blows out of the defrost no matter what control is set on.

 

Question

caseym02, Knoxville, TN, December 13, 2012, 15:59
 Rookie

problem has occured for the past 2 weeks.

4 Answers
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  • Answer #1

    pushrod December 13, 2012, 16:04
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     Master

    Vacuum leak under hood pass. side near firewall.

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  • Answer #2

    Tomiko December 13, 2012, 17:03
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     Journeyman

    maybe your blend door is broken

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  • Answer #3

    PARTS GUY December 14, 2012, 01:56
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     Master

    You have lost your vacuum to the control head. You most likely have a bad control head. Defrost is controlled by vacuum not a blend door.

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  • Answer #4

    Greg's Orange Auto (13601 Answers) , Orange, CA - (714) 361-9386
    globalhelper December 14, 2012, 06:31
     Master

    all three are good answers

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