Transfer case keeps trying to engage 4WD

[TNT]

The truck's been sitting for 3 weeks. I start the engine to warm it up and I start to walk away; I can hear the transfer case trying to engage, then release, then try to engage and so on. I open the door to verify it is in 2 wheel drive (electric operated 4WD), and it is, but the dash indicator is slowly flashing 4 low. Then I turn the knob to 4WD and the indicator flashes a couple times then stays on solid (like normal). I get in to move the truck, it is still in 4WD, I move a few feet then select 2WD; the transfer case starts engaging and releasing and the 4 low light flashes slowly again. I switch between 2 and 4WD repeatedly while moving forward and then reverse. Nothing changes. So I try selecting 4 low, no indication and then the transfer case neutral light blinks, but I'm in 4 low! WTF? I tried for over an hour, and yes I even read the operating manual, nothing changed from what I have previously described.
I drove down my drive, then backed up the drive and was about to give up as it was dark now, when things really got stupid. The head lights started flashing, the transmission position indicater lights all lit up, the "transmission temperature high" light came on and the engine shut off. The engine would start right back up, but would die right away. I gave up for the evening.