I just had this problem fixed. I had the windshield replaced and it wasn't sealed properly and water dripped on the Gem module . The beeping was the airbag system shutting down and alerting you. You probaly have had funny clicking noises under the dash with the truck off and no key in the ignition and the window and door lock lighted buttons blinking too huh? It is located on the back side of the fuse block under the dash. It is a simple fix and I did it in my driveway. Costs about $160 with a dealer discount. Also there is a recall on crank posistion sensor for 7.3 psd's 99-03.

 

I have the same problem with my windshield. I need to get it replaced before it rains again

 

My door ajar on dash light comes on intermittently while driving. I put a switch to the cab/cargo light fuse to manually shut lights off. I here a click while truck is running and lights go out. But idiot light stays on. Do u think it is my gem?

 

More then likely it is the door switch. Drivers side is the most common.

You can normally get it working again with a bunch of WD-40 sprayed into the lock mech and door latch. Hose it down good. Then open and close the door a bunch.

Worst case you have to pull it out and replace it.

 

Did you ever figure this out? I've been driving one of our fleet trucks this week, an '01 F350 base model, gas motor. Power nothing. Logged in here to see if I could find anything out about this same issue, after the dealer listened to it and said they don't know what it is and I shouldn't worry about it. Same exact pattern. Every time you start the truck, 20 seconds later it rattles off five sets of five beeps five seconds apart. Then if you drive it long enough, it'll do it every once in awhile while driving around, but always five sets of five beeps, five seconds apart. Exactly. No idiot lights, everything else working fine, no other noises, nothing suspicious going on. It's driving me crazy!

 

Idk what year they started but the seat belt minder will drive you crazy if your riding around with it unbuckled

 

No, I use the seat belt, and it's actually a completely different tone than the seat belt chime. I'm thinking it's probably the leaking windshield that others have talked about so far.