4x4 either stuck or not working???

[Abraxsis]

This past week my 93 EB X seems to have lost its ability to go into, and perhaps come out of, 4WD. I cant really tell if its stuck in 4HI or 2WD. But when I press the button all I get is a slight dip in RPM's and the indicator lights don't come on. I cant hear any unusual sounds coming from underneath. Im currently reseting the computer hoping that throws it back in to 2WD if in fact it is in 4WD. Ive been told that it could be either an electrical problem, or a vaccum problem. Does the vaccum have anything to do with the 4WD engagement?
Ive searched the forums but all the one like this are dealing with being stuck in 4LO, which I dont think is the case. Any help is greatly appreciated.

I think Ill pick up a code reader from Walmart tonight, they have them for 20.00, and I think its obvious I need it.

 

[PekingMan]

Try this link for a solution to your problem.

Dead Link Removed

Yours problem sounds a little different, but it might work for you. Its pretty easu to do and anybody with a 4wd Ex should do anyway before their motor decides not to work when they need it most.

 

[MrShorty]

Vaccuum doesn't have anything to do with the 4x4 engagement on 1st generations. Your 4x4 engages using an electric motor on the transfer case that moves through the transfer case positions (and is known to have problems) and auto locking hubs (unless you have swithced to manual) at the tires that engage based on torque being applied to the front driveaxles. I'm surprised you haven't found something dealing with this here, because it has been discussed many times, usually dealing with the electric shift motor or the electronics leading up to it.

 

[Abraxsis]

Well I may have tracked down the culprit. When I bought my X the seller said there was a small leak in rear window, and that if I brought it by sometime he would seal it up for me. Well college started and all was still fine, then say hello to Hurricane Isadore! I think the processor in the LR quarter panel got wet. Now we have some sunshine and Ive rigged some protection for the controller board, but it might be fried. Im trying to dry it out using a hairdrier for 5 minutes on then letting it sit for 20 minutes to cool and evaporate the water out. Its not working yet, Wish me luck that it does.