Flashing Green 4x4 Indicator

Haven't gone off-roading for over a week, but when I started my truck yesterday the GREEN 4x4 indicator remained flashing. It eventually turned off after a few hours during a right turn, but when I started it up today it stayed flashing again. Is anyone familiar with this problem? Thanks!

 

Oh yeah, I've checked that too. As a matter of fact I've tried switching to 4-wheel drive and back, and it won't engage. I was running some creeks and streams a week ago and I wonder if I got water on the connectors. I have skid plates underneath so it's hard to check things sometimes, but as soon as the rains stop I'll check. Otherwise, I might be SOL and have to take her in to the shop.

 

what skid plates do you have? where did you get them?