my heater blower won't run on high speed

1991 CHEVROLET S-10
78,000 MILES
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AFASTER69
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  • 1 POST
my blower runs very slow on lower settings and not at all on high,
I have replaced blower motor and resistor thingee.
Oct 5, 2011 at 4:09 PM
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JDL
  • CAR REPAIR CONTRIBUTOR
  • 16,098 POSTS
Check the actual voltage reading at the blower motor, check ground also.

When hi blower relay is energized, battery voltage goes to the blower motor. No resistors for high-speed.
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Oct 5, 2011 at 4:20 PM
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