I just purchased a 2000 GV, Automatic Tran. with manual 4WD shifter. The shifter moves but it does not engage the 4WD.  Also, no 4WD indicator lights up on the instrument panel.  Could this be a fuse?  I found the main fuses under the hood, but the owners manual does not list one for 4X4.
Thanks for any reply.

Are we sure that it doesn't engage? Maybe it does but the indicator is malfunctioning. On my samurai, This is the case. Loose wire I'm sure. You should be able to feel a slight clunking when you do a hard turn in 4wd.  At least that's what I have been told, and it seems to be true. Not sure if that's how to tell on yours though.

-Adam

Are there not more fuses under the dashboard? It seems highly unlikely that the 4wd doesn't go through a fuse somewhere. I have the schematics for this on my PC at home I will check later.
I thought that the Check Engine light would be lit if there was a problem with 4x4 selection. The diff is engaged by air pressure/vacuum. Get underneath and follow the air line back to the pump, have someone select 4wd and you should hear the pump operate. If the pump isn't working check the power to it. Also check the switches on the transfer case and the wiring in that area, the problem could be in that area, after all if the ECU doesn't know that 4wd has been selected it can't flagg an error.

Thanks Rhinoman.
One of the vacuum line hoses was disconnected at the pump, under the right front bumper.  It was an easy fix, even for a novice.  You saved me at least $150 (min anybody would take to diagnose the problem)

Thanks Rhinoman.
One of the vacuum line hoses was disconnected at the pump, under the right front bumper.  It was an easy fix, even for a novice.  You saved me at least $150 (min anybody would take to diagnose the problem)

No problem, thats the board is here for. Other people have saved me time and money in the past.