2003 Other Toyota Models No 4 wheel drive

I am an active 4 wheel drive nut, whom loves weekend adventures. While going on vacation this Saturday, my 2003 Tacoma decided that it did not want to engage into 4 wheel drive. The drive seems to be engaging, but the front wheels will not move.
There is power to the housing and everything looks in order, but it still does not engage.

Any suggestions.