I haven't use the heater fan in months . However, today I tried it and it did not turn on (any speed ) . The fuse is OK. Would someone please suggest a troubleshooting procedure for this joib ?. I don't want to take a lot of this a part that won't help me identify and fix the problem. - Thanks

 

I would get a test light and start at the fuse and work my way to the ground wire.
Hint, if it does not work on high then the Blower Resistor is not the problem.

Here is a diagram:


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