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Discussion Starter · #1 ·
Ok so i removed the blower motor and hooked to a battery to find out it still works. The wiring is fine and i know its not the resistor because it works on high. There is power to the motor at all times and is controlled by the ground i can make the motor run in the truck by jumping a ground wire to the plug in. So is the hvac switch bad?
 

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Most likely it is your resistor. When on high, there is a relay that bypasses the resistors and sends battery voltage to the motor. The lower speed settings run through a series of resistors to limit current and slow the motor.

Every blower I have had that worked on high and not lower speeds. the issue has always been with the resistor.
 

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Discussion Starter · #3 ·
I ment to say it doesn't work on high sorry.
 

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Most common problem is the resistor. Be sure to replace the wire connector at the same time as the resistor.
 

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I'm pretty sure that the high speed relay is in one unit with the resistor board. Unless that changed with the NBS, someone correct me if I'm wrong. It was only a $20 part on my 02 but yours it a bit more costly.
 
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