Chevrolet Repair: 1992 chevy 4wd not working, model trucks, test light

Question
I have a 1992 chevy 4wd. The 4wd is not working. I assumed it was the actuator that usually plaques these model trucks. I have installed the new actuator and it still does not work. I have confirmed the old one was bad.
The fuse is ok. I am showing 12 volts on a volt meter at the connection. When I use a test light there, I do not have enough current to turn the test light on. Is there a relay in this circuit that could be bad.  

Answer
Relay, no...I don't think so, but you didn't mention what year and model you have so I can't say for sure.

There is a switch on the transfer case, and it, ot any of the wire connections could be bad.

The fuse could be loose. Try a different one.

Van