Fan on after shutdown

[WILLAT4]

I turned off my 2025 yesterday and while in truck the fan randomly went on high for about 15 seconds. Anyone else have this happen? I have 3026 miles on truck. No issues whatsoever.

 

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[gemarsh]

Engine fans? No cel on?

 

[gemarsh]

The engine fans will come on, if the ecm thinks the engine is too warm. The 6.6d trucks will even fire the engine back up if the ecm deems it necessary.

 

[gwagers81]

Is your coolant level good? My ford would do that, and about paid some serious money to have them start trouble shooting it. It was so loud and would stay on for a long time after shutting it off. I did some research and found out that the coolant systems will run an aux emergency fan when the truck thinks it’s out of coolant. Mine was just below the sensor in the tank. I let the dealer service it, soI assumed they had been topping it off. Topped it off and never did it again.

 

[R467X]

I turned off my 2025 yesterday and while in truck the fan randomly went on high for about 15 seconds. Anyone else have this happen? I have 3026 miles on truck. No issues whatsoever.

What were you doing before you parked? What was the temp outside? And is it gas or diesel?

 

[WILLAT4]

What were you doing before you parked? What was the temp outside? And is it gas or diesel?

It was the heater/ac fan that came on while I was in cab with nothing on.

 

[gemarsh]

It was the heater/ac fan that came on while I was in cab with nothing on.

Sounds like the afterblow function in the firmware was enabled.