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?