Question about 2002 Chevrolet TrailBlazer

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Blows heat at all times even when ac is on with temp setting on cold

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  • Jeffrey Turcotte
    Jeffrey Turcotte Oct 24, 2010

    blend door may be stuck open. Do you hear a clicking behind the right side of the dash? If not, try calibration:

    with the ignition switch to the OFF position.

    Remove the HVAC B fuse (might be in engine compartment relay box) for a minimum of 10 seconds.

    Install the HVAC B fuse.

    Start the vehicle.

    Wait 40 seconds for the HVAC control module to self-calibrate.
    If this doesn't fix it, pull the actuator and see if door is jammed or actuator is not working.

    If you have more questions or need instructions, please let me know.



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It sound as if you have a stuck heater control valve give the websites a try and if all fails stop by your local library and get your hands on a Haynes auto repair manual for your SUV wish you the best of luck Michigan Man.

Posted on Oct 24, 2010


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