Cooling fans do not turn on

2002 PONTIAC BONNEVILLE
140,000 MILES • 3.8L • V6 • 2WD • AUTOMATIC
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NOTAPROMIKE2
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Car sat for two years. Put in new battery got car running. Started to overheat because cooling fans will not turn on. It was eighty degrees outside. A friend pulled out some relays and may have plugged them in upside down. Where do I start? Are there fuses also?
Feb 16, 2018 at 8:57 AM
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WRENCHTECH
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What do you mean by "starts" to overheat?

These fans are not programmed to turn on until approx 226 degrees which may seem hot to you but that is entirely intentional on the engineers part. Try turning the AC on and see if that triggers the fans to come on.
Feb 16, 2018 at 3:07 PM
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NOTAPROMIKE2
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starts to overheat as in the coolant is boiling into the overflow box and the car is pouring steam, but the motor has not seized up.
Feb 16, 2018 at 5:04 PM
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WRENCHTECH
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Do the fans turn on with the AC or not?
Feb 16, 2018 at 5:07 PM
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NOTAPROMIKE2
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No.
Feb 17, 2018 at 7:04 PM
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WRENCHTECH
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Okay, sounds like there is an issue with the fan circuit. The best I can do is give you the wiring diagram but you may have to get a local shop to diagnose it for you.
This is a two speed system so it is very surprising that neither speed works.

Here is the diagram.
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Feb 17, 2018 at 7:15 PM