The BCM program fuse on a 2005 Montanna SV6 is called something different in the manual. It's called a “Keyless Entry Module” fuse and it is fuse #7. The fuse panel is located on the passenger side on the side of the dash. There is a cover with an indent hole in it to pull the fuse cover off. It's really hard to pull it off and it almost seems like your going to break it when your trying to get if off. Keep pulling, it will come off! On the fuse cover, fuse #7 is labeled " RFA MDLS" which is again different than what is in the manual. I followed the procedure to reprogram my "Key Fob" and within 45secs, I had reprogrammed my key FOB! I was so excited, because, I have been trying locate the BCM fuse for 4 weeks. I think GMC does not want us to know it’s location or name, so you would have to go into a dealership to get your Key Fobs reprogrammed costing about a $100 for a minute of work.
Keep the windows open as a safety measure, then,
Remove the ignition key from the ignition lock cylinder.
Remove the “RFA MDLS” (fuse #7 ,BCM PRGRM fuse, Keyless Entry fuse) from the fuse panel.
Close all of the doors.
Close the liftgate.
Turn the ignition lock cylinder to ACC.
Turn the ignition lock cylinder to OFF, and then back to ACC within 1 second.
Open and close any vehicle door. A chime will be heard when the system enters the BCM programming/diagnostic mode.
Press and hold the transmitter LOCK and UNLOCK buttons simultaneously for 14 seconds.
After 7 seconds, a chime may be heard confirming successful programming.
Repeat the previous step on each additional transmitter to be programmed.
Remove the ignition key from the ignition lock cylinder
Install the “RFA MDLS” fuse ( fuse #7 ,BCM PRGRM fuse, Keyless Entry fuse) back into the fuse panel.
Press on the key fob functions (EG. Lock, Unlock) to verify correct operation.