My atc light came on, and information status said reduced engine speed on 2004 Chevrolet Tahoe

I was basically dead on the road, engine was on, but I could not move. I stopped, turned off ignition,restarted and it was fine, what is causing this?

Asked by for the 2004 Chevrolet Tahoe
It needs to be scanned for history faults, and which module asked for the reduced power to the ECM.