4x4 problems

[mudplayer]

I have a 94 Explorer 4x4. The problem i have is the 4x4 will not engage.the light comes on on the dash but it makes a sound in the front like its not in all the way,the low lock light will not come on as well.the 4x4 worked great last year just started this problem.
we had the bearings packed when we purchased it in2001.Need help.

 

[Henry]

Two things quickly come to mind regarding this problem.

First, the computer may have "forgotten" where the shift motor is positioned. Disconnect the battery for a few minutes, then reconnect and try the 4wd button.

If that doesn't help then it is possible that the shift motor is dirty inside. One thing to try is to repeatedly engage and dis-engage the 4wd (not too quickly, let the system complete the change between button presses). This will cause the shift motor to repeatedly rotate, hopefully cleaning any dirt off the contacts. If the 4wd engages properly, then try between 4wd high and 4wd low.