Engine cooling fan system not working

2006 NISSAN SENTRA
102,990 MILES • 4 CYL • AUTOMATIC
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KIRSTIEMADDOX
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  • 2 POSTS
My engine cooling fan only works with my A/C on and not with it off. I already replaced the temperature control sensor.
Mar 9, 2022 at 5:55 PM
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SQM
  • AUTOMOTIVE REPAIR CONTRIBUTOR
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Hello,

First of all are you experiencing over heating?
As you know the radiator fans are designed to come on with the A/C to provide proper cooling.

https://www.2carpros.com/articles/how-an-electric-cooling-fan-works

Also, the radiator fans might not come on if there is no need for it to come on as if the thermostat opens at a lower temperature or if you have been driving colder than usual climate.

This vehicle is equipped with two cooling fan relays, high and low speed relays. Check those for functionality.
They are located under the hood fuse box (see diagram below).

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Please let me know little more of what you have been experiencing.
Thank you.
Mar 9, 2022 at 7:43 PM
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KIRSTIEMADDOX
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It hasn't gotten to overheating yet, but I also drive with A/C on just so it doesn't. I have let it run and noticed the engine was hot with no change to the fans not coming on with the A/C off. I switched the relays around just to check if it will come on and no change the temperature would fluctuate in the middle. I've had a car problem prior with a Buick I purchased the fans stopped working and the engine got hot, and it blew. so, I'm desperately trying to figure out and fix what could be the cause of this too because I don't want the same thing to happen.
Mar 9, 2022 at 11:25 PM
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SQM
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 6,383 POSTS
If the relays are good, the sensor is good, the fan is good. The issue could be a faulty signal wire for the temperature sensor or issue with the ECM that is not triggering the fan. Check to see if you are getting 5V on the signal wire of the temperature sensor.
Mar 10, 2022 at 11:09 PM