there is a section in the 2013 motors book i read it a few days ago and it tells u to take key out of ignition for 30 secs if u had the truck on. i cant find it at the moment but if i do i will post it for u
I've done many hundreds of GMs. Usually, 30 seconds is overkill, along with all of that lock/unlock jazz; I usually just turn it completely off and count to at least ten seconds before turning it back on, and that's enough. On several of the OBD1 Cadillacs, the MILs only come on during actual cranking. That's not in the precious book, though ... if you follow SCIP to the exact letter, you will wrongfully fail them.