1999 gmc fan not blowing right....

1999 GMC SIERRA
142,000 MILES • V8 • 4WD • AUTOMATIC
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TSTUCKE
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  • 1 POST
I recently put a heater resister switch in my gmc sierra 99. AND I HAD SPEEDS 1 THROUGH 4 and the day after it wouldn't blow anything now all of a sudden setting five will on work. What could be the problem now.
Dec 16, 2010 at 9:40 AM
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JACOBANDNICKOLAS
  • ✓ASE Certified Mechanic
  • 110,194 POSTS
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Based on the problem described, you blew out another blower motor resister. The most likely cause is a bad blower motor. If the blower motor is drawing too many amps, it will fry the resister and you will end up with high speed only.
Jan 13, 2011 at 8:29 PM
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