I know someone who's S-10 99 won't shift out of 4wd. I'm told it has a button sto shift with out of 4wd high range into 2wd. I havent seen the truck but I told them to check fuses since it seems to be electronically operated. Any help would be appreciated.

 

Pull the fuse. Driver side sail panel. 10A it's red one.

 

Actually the buttons in the dash for the transfer case and front axle engagement are electronic but the actual mechanical method uses engine vacuum to go between 2HI and 4HI. And then there is the 4HI to 4LO which is more closer to your idea of electronic.

There is a vacuum "ball" under the battery tray that causes a cable to the front axle to move in or out depending on whether you are in 2HI or 4HI. Check all the vacuum lines leading to this ball. You can also check operation of the cable to the axle by removing the cable from the braket under the battery and using a pair of vise grips to push and pull the cable. If it does not move then there might be a problem with either the cable (frayed) or the axle portion of the mechanism.

Good Luck...

 

Or it could simple be axle bind. Drive in the dirt for a little and try to take it out of 4wdr.