fan blower motor resistor replacement

1994 VOLVO 850

150,000 MILES • MANUAL

LORNEMAC

MEMBER
2 POSTS
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After I learned the reason why the fan motor blower only worked on high, I bought a new resistor online. I installed it, and tested the low, med and high settings. The settings worked, but then I noticed that smoke started coming off the resistor, so I immediately shut off the fan and turned the car off before permanent damage would occur.

Should I replace the fan motor? Clean the fan motor more thoroughly? Do something else?

Thanks,
Lorne

Oct 20, 2016 at 1:24 PM

CJ MEDEVAC

CERTIFIED EXPERT
11,004 POSTS

You had the resistor installed when it was it smoking or were you fiddling with it uninstalled?

The Medic

Oct 20, 2016 at 3:00 PM

LORNEMAC

MEMBER
2 POSTS

Yes, I had just plugged the new resistor in, turned the ignition and fan on, and tested the fan blower's low/med/high settings. The fan motor was still making a noise like before (even after lubricating it), but the low-high settings seemed to work fine for about 25 seconds. Then I noticed smoke coming from the resistor and I turned the fan and car off. I'm guessing that I might have to take the fan blower motor out again and lubricate it better this time...?

Oct 22, 2016 at 10:05 AM

CJ MEDEVAC

CERTIFIED EXPERT
11,004 POSTS

Mr. Resistor is a "resistor", he sorta resists/ restricts electricity. When the juice is restricted something starts building up heat, that would be resistance wire of the resistor (kinda like an electric stove eye).

Most blower motor resistors sorta permanently poke their head into the duct work of the HVAC unit. Reason being, when the blower fan is turned on it's air is blowing over it. Not only does it keep it cooler, it also prolongs the life of the resistance wires.

Smoke would be normal if it were not installed.

In an emergency situation, MacGyver could snatch it out to start a fire, or simply light up a menthol during a nicotine fit!

The Medic

Oct 22, 2016 at 7:25 PM