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Visually inspected the terminal blocks for damage, found none. Checked the orange wire for continuity between the two terminal connectors and it check out ok. Checked the other wires between the two terminal blocks and those were good as well. When I first started trouble shooting I replaced the climate control assembly first and tested high fan speed. After that did not solve problem I replaced the blower resistor which had obvious signs of being defective (dark spots on the board). So I am thinking that I possibly burned up the circuit board inside the used replacement climate control unit since I installed and tested that before replacing the blower resistor. No sure how familiar you are with the inner workings of the control but I took one apart for inspection and the fan control knob has two copper fingers (brushes?) that drag across a circuit board inside the control as you turn the knob. Your thoughts?
Check to see if the is power on the orange wire comming out of the control unit with it on high, if so then the wiring is the problem or you have a bad terminal in the connector........So if orange wire has power out of control unit when on on then make sure connections are tight and replace wire. If no power c omming out of control unit then replace the unitl.
I tested voltage at the connector coming from the control unit and I have 12 volts there with the switch on high. Tested voltage at the blower resistor connector and I have 12 volts there. Both harness connectors at the control unit and the blower resistor are tight and look fine. Just to cover the bases I did install a tempory jumper wire from the control to the resistor (the orange wire) and that made no difference. Not sure what to do now. Keep in mind I did not have high speed before I replaced the blower resistor.
If you have good voltage at each speed on the resistor and good ground on the black wire then the problem is either the resistor or blower motor, I would replace both. Here is a wire diagram so you can see how it works.
I rechecked the fuse panel. Didn't realize it had two fuses for the blower. The 25A fuse for the high blower was missing. I bought the car used so who knows why it wasn't there. Originally I checked the 20A fuse (for the lower speeds) and it ok so I moved on. Sorry for the run around, I had a feeling it was something simple that was being overlooked. Thanks.