How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask greasemonkey2386 Your Own Question
greasemonkey2386, ASE Certified Technician
Category: Car
Satisfied Customers: 274
Experience:  ASE Certifications A1,A4,A5,and A7 10+ years professional hands-on experience
Type Your Car Question Here...
greasemonkey2386 is online now
A new question is answered every 9 seconds

Saab 9-3 2.0T: I suspect the cabin fan blower resistor on my

This answer was rated:

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?

hello, when resistors go bad they typically will only work on high not low, have you checked to see if you are getting signal that changes when you change blower speed?
Customer: replied 4 years ago.

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.

you should be getting 12 volts on high
Customer: replied 4 years ago.

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?

its possible, what happens if you supply 12 volts to the fan?
Customer: replied 4 years ago.

When we supplied the 12 volts, the fan blew full blast instantly.

the fan control unit is bad in my opinion, you have 12 volts inbound from a fuse and the voltage is adjusted internally to control fan speed
greasemonkey2386 and 9 other Car Specialists are ready to help you