fan motor runs only on high speed

2003 PONTIAC GRAND PRIX
99,000 MILES • 6 CYL • 2WD • AUTOMATIC
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LARRY 1
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  • 1 POST
I have replaced resistor.Fan motor does not work on speeds 1-4 and is also affecting the day-time running lights.checked all fuses and circuits.All good Checked ground-no problems This is on a 2003 Pontiac grand Prix Could you help?
May 22, 2011 at 11:19 AM
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JDL
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  • 16,098 POSTS
Did you use a voltage tester anywhere? Check voltage at the applicable fuse/s.

In the diagram, when the relay is energized, only high speed. When relay isn't energized, continuity for lower speeds. At the blower motor, terminal A is voltage, terminal B is ground.
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May 22, 2011 at 11:36 AM
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OBXAUTOMEDIC
  • ✓Experienced Mechanic
  • 3,711 POSTS
Hello,

The Blower Motor Resistor is famous for this problem you are having. It is mounted in the duct work under the passenger dash near Blower Motor.
May 22, 2011 at 3:17 PM
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