i have a 1993 f150 with 4 wheel drive. the relay behind the glove box clicks but will not engage. the lights in the dash and on the button the button wont turn on ether the truck doesn't have locking hubs? i have no idea where to start i have a haynes book but i cant find anything in there about what might be wrong and i have no idea were to begin.

 

probably the transfer case motor.

 

Get a test light and test to see if power is going to the switch, could be a bad switch. I've heard fairly simple fixes for the electric 4x4 problems. Hope you get her fixed

 

its your transfer case motor. mine had same issue. you hear it click and the lilghts flicker but wont engage . swap out that motor.

 

I agree, it's most likely the transfer case motor. Typical. I also agree with starting to check other things with a test light first.

 

i have a similar problem, i have a 94 f150 4x4 with auto locking hubs. I can hear the relay on the passanger side glove box click. The light on the push button comes on when pressed and stay on, but the hubs wont lock and the low range button wont come on at all when pressed. Any help is appreciated....