I have a 1994 Chevy S10 Blazer 4X4 with the Electronic 4WD. It doesnt work at all. I dont get any indicator lights, noises, nothing, when I try putting it into 4Hi or 4Lo.
I did a little test of my own as well to see if it was working, by letting it run in park, turning on the 4WD, and spinning the front driveshaft with my hand, it spun, which means it deff. Was not engaged.
I dont know much, but I do know my way around the engine and can fix things on my own with a little bit of an idea as to whats wrong but I'm lost. Maube a blown fuse? : \
There is a motor in the transfer case to engage the 4 wheel drive, it sounds like your's is froze up. This happens when there is a long period when you do not engage it. You can have the motor replaced and should fix your problem.