2004 Pontiac Grand Does PCM Supply 12 Volts Fan Relays Don T Voltage Motors

194,000 MILES
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ANONYMOUS
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Does the PCM supply 12 volts to the fan relays? I don`t have voltage at the fan motors, at 220 degrees.
Jan 2, 2013 at 12:54 PM
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JDL
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The pcm controls ground for the relays, not voltage. Did you check for voltage at the relays? There are fan fuses in the under hood fuse block. Will the fans run if you turn on the ac? If you unplug the coolant temp sensor will the fans run? Any applicable trouble codes?
Jan 2, 2013 at 1:09 PM
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JDL
  • ✓Experienced Mechanic
  • 16,098 POSTS
Just to add, low speed fans come on around 223 degrees F. The high speed around 230 degrees F.
Jan 2, 2013 at 1:15 PM
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