Disable Alarm on 99 D

My son had a problem over the weekend at college with this truck. His remote stopped working last week (new batteries were just installed a few months ago and it has worked fine up until this point) but he was able to lock the doors manually. When he got in to go to work on Sunday, the alarm started going off and he couldn't start the vehicle. I had him disconnect the battery ground while we tried to figure it out but it would erratically start alarming again when he reconnected the ground wire. Finally he took the batteries out of the remote, put them back in and it's now working OK.
There doesn't seem to be any fuse or relay that's specifically for the alarm and my Haines manual doesn't even cover it. Probably disconnecting the alarm is not something they really want to advertise but since he's away from home I'd rather he be able to disable the alarm and drive the vehicle if it ever acts up again. I'm not really concerned about someone stealing the truck.
Anyone know how I can get around it?

Thanks - T-bank

can not be done he should get the switch at the door key cylinder checked or replaced as this is another way to disarm the alarm by unlocking the door with the key if the rke fails