Why are Check Engine, VSC Trac and Trac Off lights all on?

PO420 is indicative of a failed catalytic converter - as for the other codes you can find the definitions and detailed information @ https://www.engine-codes.com/ The other system (VSC) rely on proper engine operation to function properly - likely the reason for other lights.

Gas cap was loose, believe it or not. Tighten the gas cap AND disconnect the battery for 30 plus seconds. Reattache the battery and start the car. It worked like a charm, unless there is a deeper problem. I just did it after reading it on a forum here.