Cooling fan will not come on unless A/C turned on then only on low

2008 CHEVROLET UPLANDER
169,000 MILES • 3.9L • V6 • 2WD • AUTOMATIC
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TED FINLEY
  • MEMBER
  • 10 POSTS
New fans, comes as AC and radiator fans. checked relays. when ground check relay fans come on high speed. just replaced transmission new.
Apr 27, 2019 at 12:17 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Good afternoon,

Try this. Remove the connector for the cooling fans. Do this while the engine is running and see if the fan kicks on.

Check the fuses I circled in the diagram I attached for power as well.

Roy
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Apr 27, 2019 at 2:42 AM
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TED FINLEY
  • MEMBER
  • 10 POSTS
Checking now. think I checked this relay, but will check again. thanks
Apr 27, 2019 at 6:52 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Sounds good. Keep us updated.

Roy
Apr 27, 2019 at 6:58 AM
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TED FINLEY
  • MEMBER
  • 10 POSTS
checked fuse, checked relay okay.
Apr 27, 2019 at 11:37 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
Did you do what I suggested with the sensor connector?

Roy
Apr 27, 2019 at 12:04 PM
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TED FINLEY
  • MEMBER
  • 10 POSTS
Yes.
Apr 29, 2019 at 12:47 AM
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ASEMASTER6371
  • ✓Experienced Mechanic
  • 52,796 POSTS
And the result.

Roy
Apr 29, 2019 at 1:20 AM
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