4Wheel high troubles

[JWBehm]

Was wheelin today at a local spot and stopped in front of a small puddle to see if it was deep or not. I ddint realize that what I was in had managed to sink a good 4 inches so I went to back up and the tires were just spinning. I tried to put it into 4HI to no avail. I finally managed to back myself out then later tried to get it to engage into 4x4 while it was moving, and it still wouldnt go. The green light on the dash did NOT come on. I went ahead and tried it in 4LO and it worked fine, light came on, no problem at all. Anyone have a clue as to what is going on? BTW pics, from after the semi-stuck
http://img.photobucket.com/albums/v221/jwbehm/CIMG0550.jpg
http://img.photobucket.com/albums/v221/jwbehm/CIMG0549.jpg

[p nut]

That's scary. I had that happen on my old 98 Limited. The light would blink, but not stay on, which meant that the 4hi did not engage. What worked (most of the time) was revving the engine and turning the wheel side to side. It works off of a vaccuum, so it helps engage the 4 wheel drive. Weird it would work on 4lo, though.