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
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  • 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 7:17 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
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 9:42 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 1:52 PM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Sounds good. Keep us updated.

Roy
Apr 27, 2019 at 1:58 PM
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TED FINLEY
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  • 10 POSTS
checked fuse, checked relay okay.
Apr 27, 2019 at 6:37 PM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
Did you do what I suggested with the sensor connector?

Roy
Apr 27, 2019 at 7:04 PM
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TED FINLEY
  • MEMBER
  • 10 POSTS
Yes.
Apr 29, 2019 at 7:47 AM
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ASEMASTER6371
  • ✓ASE Certified Mechanic
  • 52,796 POSTS
  • ASE Certified Mechanic
And the result.

Roy
Apr 29, 2019 at 8:20 AM
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