My AC/ heater fan stopped working

RICKEYE

MEMBER
2003 GMC SAVANA
80,000 MILES

Won't work on all speeds. I checked the relay and its fine, tested the fan and it works, bought a new fan resistor and plugged it in and still not working. What else could it be?

Tuesday, February 26th, 2013 AT 6:51 PM

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

So, we need to take a step back and check for voltage coming into the resistor from the fuse on the red wire.

Basically, if we don't have 12 volts on this wire then the fuse is the issue.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Otherwise, we have an issue with the switch.

So, if the fuse is okay, then we need to check the voltage at the HVAC assembly or resistor on the other circuits. I suspect the control assembly will be the issue but let's use these guides to help with this testing:

https://www.2carpros.com/articles/how-to-check-wiring

https://www.2carpros.com/articles/how-to-use-a-voltmeter

I am attaching the wiring diagram below that will help with this.

Please run through this and let us know what questions you have with this, and we can go from there. Thanks

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