Question about 1998 GMC Jimmy

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Heat won't shut off in my 1998 Jimmy

I cannot get my Jimmy to quit blowing heat! I know it is not the A/C. I can change the temp from the 82 on the right side of the knob to the 62 on the left, and it still blows heat. I shut the fan off, but in the summer, it is killer. It still heats, even if the fan is off. I was told that it could be a computer malfunction.....is this possible, and is it expensive to replace?

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  • chachopapa Aug 08, 2008

    my heat is on all the time ever after is turned off.

  • Anonymous Aug 28, 2008

    I need help I would like to know how you can install a blend door actuvator maybe you can help

×

1 Answer

I would suspect your blend air door is in the full open position, which is the default position if any of your hvac sensors report a problem. This could be a sensor problem, a module problem, a mechanical problem, or an unrelated trouble code stored in the body control module. Best to have an Auto tech take a look at it.

Posted on Aug 03, 2008

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