04silverprix
New member
Okay, I think I may have pinpointed why the fan will not work on my 2004 Grand Prix. I replaced the resistor, the blower motor checks ok (I even put in another motor and it still wouldn't run), re-installed the OEM blower motor, checked the fuses again and nothing is blown there. The air conditioner compresssor still kicks on. I just don't have a fan.
That leaves the fan switch. This is integral with the whole HVAC control. The switch for the fan is like a rheostat, so there isn't a notch for 4-5 different speeds. The control for the air ducts seems to work because I can hear the module for that run. Besides, even if that didn't work, you'd think the fan would still run.
I checked again with a test light and found there is no power to the blower motor. That leaves the fan switch as a potential culprit.
I already popped the instrument panel apart and got the unit to where I could unplug it. However, if I don't know which terminals to direct my test light to, how will I know if it is defective? The Haynes manual I have primarily covers the earlier Grand Prixs and doesn't have a wiring diagram for the controller.
Does anyone have access to the schematic for this circuit, or knows which terminals to contact for a test? I think it could be defective, but I want to make sure before spending $150-plus for the replacement. I wonder if a GM service department would provide the information?
Any thoughts would be appreciated.
That leaves the fan switch. This is integral with the whole HVAC control. The switch for the fan is like a rheostat, so there isn't a notch for 4-5 different speeds. The control for the air ducts seems to work because I can hear the module for that run. Besides, even if that didn't work, you'd think the fan would still run.
I checked again with a test light and found there is no power to the blower motor. That leaves the fan switch as a potential culprit.
I already popped the instrument panel apart and got the unit to where I could unplug it. However, if I don't know which terminals to direct my test light to, how will I know if it is defective? The Haynes manual I have primarily covers the earlier Grand Prixs and doesn't have a wiring diagram for the controller.
Does anyone have access to the schematic for this circuit, or knows which terminals to contact for a test? I think it could be defective, but I want to make sure before spending $150-plus for the replacement. I wonder if a GM service department would provide the information?
Any thoughts would be appreciated.