Ok so I’m trying to put in new stereo without wiring harness. Will not be powering any speakers with stereo. All I need is power to the stereo. I pulled ground wire out of ribbon connector, ran a wire from fuse box under rear seat that is hot all the time for memory and power, ran another wire from fuse box from the Retained accessory power fuse, for my switched power. The problem....stereo don’t turn on and sunroof won’t close (no power). Any help would be very much appreciated !

Closed duplicate thread for this issue: https://www.gmforum.com/2000-2005-90/help-312694/

Please refer to this thread for all future activity related to this issue.

It'* difficult to know where to start without more specifics. I'd suggest you return things back to normal one by one and see what gets your sunroof functionality back. Also, I'd have to be pretty desperate to pull anything from a ribbon cable. You take a great chance of altering a tightly-designed power system and damaging modules.