4wd not working

I have a 93 Jimmy and when I push the 4wd button it doesn't do anything whether it be 4hi or 4lo it does nothing. The button doesn't light up nor do you hear it enage. I replaced the switch already and that did nothing. I heard from a guy to try unplugging the T-case shift module so I did that a few months back cause of having the same problem and it worked the 4wd worked. So low and behold now that I have it up for sale and have a buyer for it, it stopped working again. I tried unplugging it again and that did nothing. I don't know what to do with it now other then to throw a brick on the gas pedal and let it drive off a cliff due to all the problems and money I've sunk into the damn thing already and like I said soon as I get a buyer for it, it stops working again :banghead: If anybody can help that would be great I have until tues to get it fixed cause thats when the guy that wants it is picking it up.

ttt

I feel ya -- my 98 has driven me into the poor house. That is a wierd problem -- not sure the answer but wanted ya to know I fell yer pain.

try th tccm reset: unplug the fuse, take off the pos lead at the batt, ground the pos batt lead against the eng for a moment, reinatall the lead + fuse, try 4wd. good luck.

Hey Man,had The Same Prob And Ultimately Ended Up Being The Transfer Decoder Motor (gm Only Part)close To $500.00 Just To Purcase The Part, So Good Luck

try th tccm reset: unplug the fuse, take off the pos lead at the batt, ground the pos batt lead against the eng for a moment, reinatall the lead + fuse, try 4wd. good luck.
I'm going to try that and maybe with some luck it will work. Otherwise GMCMAN could very well be right about the Transfer Decoder Motor.

I was looking at the posi lok system and am thinking of maybe just switching to that but am not sure. So this is probably a dumb question, if I switch to the posi lok system would I have to even worry about fixing the current problem with 4wd? or does that have to be working in order to use the posi lok system? I know a dumb question but just want to be sure. I figure the posi lok system is fairly cheap and would at least get the 4wd working if nothing else.

No posi-loc will not help it replaces the frnt axle actuator not the encoder motor witch controlls the transfer case shifting.

Woohoo it's finally working. I went in by the fuses and there's a TCCM fuse which was fine but I noticed a plug above that says I think battery on one side and TCCM on the other I touched the TCCM wire which is a male into a female end kinda thing and it wasn't all the way in. Pushed the wire back in and voila the 4wd works. Damn I'm happy it's working finally. At least it was an easy fix. Now it's time to sell while everything is working