I've checked every vacuum line I can find and still nothing I do like the cable idea or posi lock just can't afford it right now is there a way I could test the electrical on it? Or does the electrical wire only switch the light on and off?

 

The wires only power your 4x4 light. Pull the 4 bolts out and make sure your actuator slids freely. Sometimes moisture can get in there and put a little rust on the slide and cause it to hang up. This happened on my 2000 half ton I used to have that didn't get locked in for a while. Also. Run a vacuum line strait from another port so u know. Your getting a good vacuum. It should pull it over and the light come on right away