Question about 1998 GMC Sierra

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Heater only works on high

I replaced the resistor, the wires look good, can it be the relay? and where is it located?

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There is a small electronic controller located in the heater core exterior, on gm's these go out, If you handy with a solder gun, generally it will be a burned lan on the circuit board, these put out quite a bit of heat, that is why it is mounter near the blower.

Posted on Dec 14, 2008

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