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I suspect the cabin fan blower resistor on my 2006 Saab 9-3 with ACC is faulty, though I am not sure. A couple days ago, I took out the blower assembly and lubricated the motor bearings and cleaned up some corrosion as the motor had seized and wouldn't turn at all. After testing the blower and re-installing it, all worked well. Within a day a new problem arose-- the blower would blow only at the lowest speed, regardless of whether it was set at low or high and turned off when the car was turned off. I have cleaned contacts on the motor and resistor. The fan blew when voltage was applied to the motor from an external source, and I checked voltage on the resistor pack that showed an increase as I increased fan power on the ACC control panel with the max being about 8 volts. I have done everything I can to insure the contacts making good contact between the resistor and motor. Any ideas? Do I need a new blower motor resistor?
Yes, I hooked up the voltage meter to the contacts on the resistor pack that connect with the blower motor. Off had a reading of zero, with an increase each time I increased blower strength with it leveling off around 8 volts at high speed. I'm totally stumped. To me it seems to point to a bad connection between the resistor pack and the motor, yet I've done everything I can think of to fix that.
That's what I thought. But, I also know that voltage does not necessarily mean current. If it helps, the fan was set to high for quite a while to get the motor to turn at all, but that was due to a very stiff (and later seized) motor. Could that have caused harm somewhere?
When we supplied the 12 volts, the fan blew full blast instantly.