1999 gmc fan not blowing right....

1999 GMC SIERRA
142,000 MILES • V8 • 4WD • AUTOMATIC
Avatar
TSTUCKE
  • MEMBER
  • 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 1:40 AM
Advertisement
Avatar
JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,240 POSTS
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 12:29 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.