Locked in Park

I've got a 1998 GMC Jimmy 4x4 Automatic that won't get out of park. I think it may be the shifter or some electronics (like the signal from the brakes), but I can't find any information on how this system actually works, or how to disassemble/diagnose.

Any help, instructions, or documentation would be greatly appreciated.

THe system is called BTSI(Brake transmission shift interlock). You may be able to temporarily bypass by pulling the turn-b/u fuse from the interior fuse panel. I am not really sure how the system works on a blazer-I'm more familiar with the fullsize trucks. With the C/K trucks you can also shift out of park when the key is between the off and on positions but it can be like standing an egg on its end at times

THe system is called BTSI(Brake transmission shift interlock). You may be able to temporarily bypass by pulling the turn-b/u fuse from the interior fuse panel. I am not really sure how the system works on a blazer-I'm more familiar with the fullsize trucks. With the C/K trucks you can also shift out of park when the key is between the off and on positions but it can be like standing an egg on its end at times

I'll double check the fuses, but the fuses were the first thing I checked after confirming that it was the shifter and not the transmission.