blower fan runs on high

1993 CADILLAC FLEETWOOD BROUGHAM
89,000 MILES • 6.4L • V8 • 2WD • AUTOMATIC
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JET CHILLA
  • MEMBER
  • 1 POST
My blower fan runs on high despite me switching to low or automatic (it is a automatic climate control).. I turned the car off, and the fan kept blowing on high. I finally pulled the wire on the blower fan to keep from draining the battery...

I never heard of a fan run by itself before so I'm thinking it's the relay (contacts stuck in on position). I would be very happy to have a second or third opinion.

I haven't checked the fuses for the obvious reason the fan is working and not stopping.
Jan 7, 2021 at 10:48 PM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Good morning,

The power module or blower resistor is shorted to power and that is why the blower is stuck on high. A very common issue back in the day.

The module is right next to the blower motor itself. I attached a picture of the part for you as well.

Rock Auto has the module for you. I attached the part below.

Roy

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Jan 8, 2021 at 3:42 AM
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