[Zack46]

Originally Posted by Glen e

A reboot of the car is called "the GM global reset" google it.

It is done this way:
Take off both batt cables and touch them together, this drains all the capacitors that still hold energy even when you pull the neg cable for 10 min.

If this procedure unnerves you, pull the neg cable and let it sit overnight, the caps then drain slowly.

And because the settings are held in NVRAM, very few of them go away on a reset.