I have a 2003 TL which came with the 6-disc OEM Bose headunit. A couple of years ago I updated my sound system with an aftermarket headunit, speakers and subwoofer. Over the weekend I put the audio system back to stock, however the OEM headunit does not turn on. I know it is getting power because when I turn my headlights on, the headunit screen's backlight turns on. But the display otherwise doesn't work, the power button doesn't turn it on, etc. I didn't cut any of the OEM wiring when I put in my aftermarket system, so everything is just like it was stock. Does anyone have any ideas why this is happening and/or how to fix it?