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1990 gmc 1500 heater motor does not turn on

1990 gmc k1500 heater motor does not turn on. There is power to the heater control and relays. The heater motor will run if hooked to a direct power source.

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The fan switch itself is a possibility, but there is also a resistor pack behind the glove compartment. Hi speed doesn't use the resistors, though, so if it doesn't run on hi, it narrows it down to the switch, the motor, the motor ground, or the blower relay, or any of the associated wire connectors.

Posted on Dec 14, 2008


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No fan

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