Question about 1997 GMC Safari

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My 99 GMC Safari has heater stuck at 75% defrost and 25% vent...no leg heat...something is stuck...how do I get at it to loosen it up or fix?

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Blend door actuator is stuck or burnt out or actuator door is jamed
locate and place remove motor actuator check if blend door move freely
if not repair or disloged foring object (pencil pen---comb---etc)
if ok before installing actuator plug back in harness and move selector switch
if it fails check for power if power replace actuator if no power check switch

Posted on Apr 02, 2011

  • dougspadafor Apr 02, 2011

    thanks will check....also GM says may be a vacuum hose leaking...how do i get at the actuator door and motor?

  • DON MAJOR Apr 02, 2011

    ussualy found under dash ?driverside if actuator system is electric
    look for kinda triangular black box 3 screws holds them in and hook up to linkage
    motor inserted over blend door actuator or pivot
    if vacumed follw tubing (diffrent colours) will go to roundish actuator that is operating blend
    door system

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