Ok here's a good one. I swapped the door panels complete with power switches between my 04 Denali and 04 2500. After doing so, the keyless/alarm remotes also swapped. It seems the remotes are tied into the driver's side power switch module. The lock/unlock works on both but the alarm will not set on the 2500 now. Alarm will set on the Denali and worked on both trucks prior to door panel swap. I've checked to make sure all doors, hatch and hatch glass are completely shut. Interior lights work correctly when any door is opened. I'm stumped why the alarm will not set on the 2500 now. Not that I really need it...just wonder why it's not setting?