2001 Grand Prix non-supercharged 3800 Series II automatic transmission. Completely lost any functionality to power windows, power locks, A/C, sunroof and stereo. All went out at the same time. Tested all fuses checked all connections and ground wiring… Could this possibly be a relay or something else simple? I could not find any information on a source that powers any combinations of what lost all power, but I’m hoping anyone may have had the same problem and found the solution or can give me ideas on what to check out next. Thanks in advance to anyone who takes the time to comment suggestions.