My coolant fan stays on?

2004 MERCURY MARAUDER
84,000 MILES • 4.6L • V8 • 2WD • AUTOMATIC
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TRUCKWES
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My coolant fan stays on. I change both temperature sensors. thermostat and bled the system. My temp gauge take about 10 minutes to move to half. Heat is okay, what could be the problem?
Jan 30, 2025 at 1:19 PM
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STRAILER
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This can only be one thing, the fan control driver inside the PCM is stuck on, I would get a rebuilt unit and replace it, you can get a preprogrammed unit by searching Google or Ebay. Here is how the repair job is done. Check out the images (below). Please let us know what happens.

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Jan 31, 2025 at 10:52 AM
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TRUCKWES
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Radiator fans stay on. Before the engine warms up. change temperature sensor and thermostat maybe computer. Where is the location?
Feb 9, 2025 at 5:08 PM (Merged)
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STRAILER
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Did you see my response?
Feb 9, 2025 at 5:08 PM
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TRUCKWES
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the coolant fan comes on as I start the car?
Feb 11, 2025 at 1:45 PM
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STRAILER
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Yes, I would check the wiring between the sensor and the PCM, here is a guide and the wiring diagrams so you can see how the system works and which wires to test.

https://www.2carpros.com/articles/how-to-check-wiring

If you have an open circuit the fans will come on. Check out the images (below). Please let us know what happens.
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Feb 12, 2025 at 9:11 AM