4x4 won't engage

i have a 1992 blazer with push button 4 wheel drive and when you push the button the 4 wheel drive won't work no lights no nothing, but when you first start it up the lights on the button flash

i have a 1992 blazer with push button 4 wheel drive and when you push the button the 4 wheel drive won't work no lights no nothing, but when you first start it up the lights on the button flash

The lights lighting up when you first start are the bulb check. Without going into too much detail the first thing you should check is the fuse for the 4WD and the relay.

i have a 93...same setup...same problem....
no mechanics iv gone to can figure it out....
and i dont want to get it on a diagnostic machine cause its kinda big $$$ if it even finds the prob.
this parts and labor......= $$$$$ ..if you got it do it.
i fix this problem by taking off the negative battery terminal off for 10 mins,,,,it works after that for like a week..then repeat this and so on and so on.
i seem to think its the 4x4 comp that is bolted to the main computer ..way up under the dash on the passenger side. (a real bioutch to get to..BTW)
the 4x4 comp is about $300 from a dealer..i got one from a junk yard..but had the same prob...
so i would buy it new...but again....ill just do the batt trick...the day before its gonna snow :)
hope this info helps.......it may..may not....good luck!!!

After checking the easy stuff. Check your encoder. They go bad all the time. They are on the transfer case.

whats an encoder? and where is it? all i saw on the transfer case was the motor acctuator.

There should be an electronic encoder motor on that year, if not your have a vacuum system.

Check all vacuum hoses and remove the vacuum actuator on the transfer case and see if it is stuck?