Engine Cooling Fan Runs @ High Speed on Cold Start-up

[Born2bwild]

2020 GMC Elevation 62,000 miles.
I have a problem with the engine cooling fans running on high speed on a cold strat-up. I imagine one of the engine temperature sensors has failed. I disconnected the positive battery terminal for about 30 minutes & then reconnected it. The truck started up without the cooling fans running on high speed. That lasted for about 6 start-ups totaling about 100 miles. I started up again this morning it was 10°F outside & the cooling fans are back to running on high speed at start-up. Any ideas why & what I should do to solve this? Where can I get a good repair manual?

 

[gemarsh]

2020 GMC Elevation 62,000 miles.
I have a problem with the engine cooling fans running on high speed on a cold strat-up. I imagine one of the engine temperature sensors has failed. I disconnected the positive battery terminal for about 30 minutes & then reconnected it. The truck started up without the cooling fans running on high speed. That lasted for about 6 start-ups totaling about 100 miles. I started up again this morning it was 10°F outside & the cooling fans are back to running on high speed at start-up. Any ideas why & what I should do to solve this? Where can I get a good repair manual?

Is the cel illuminated?

 

[Born2bwild]

Is the cel illuminated?

No the CEL is not illuminated, otherwise I would have connected my OBD2 reader. The shutters are in the open position. I thought maybe they would be stuck in the closed position. So not sure if it's a position sensor, a temperature sensor or the ECM causing the issue. Last time disconnecting the positive battery terminal reset the fans for a short while. Any suggestions on troubleshooting & on where to get a sevice/repair manual for the 2020 GMC?

 

[Born2bwild]

Well it's doing it again. Today it's negative 25 degrees F outside at startup. Both engine cooling fans once again came on at full speed. Engine block heater was plugged in. No hesitation starting up. Not sure what is causing this. There is no CEL on & no codes present. I will look for more engine cooling system info on this engine. I think that the last time I read there is a coolant control valve that moves to adjust & direct coolant flow, Maybe it's in an abnormal position? Any ideas or suggestions? Thanks!