I need help,my 2001 dakota has no lights to the 4x4 switch,I removed the switch I do have power to one wire,but when I turn the switch to 4 high or 4 lo nothing happens ,I need help diagnosing the problem,thanks

If you have no four wheel drive at all, sounds like a vacuum problem at the transfer case. If you can, get underneath the truck while it's running, pull off a vacuum hose the the transfer case and feel for vacuum.

There is a switch on the transfer case that gives the indicator light the ground when you engage the four wheel drive. I think it is on the top of the transfer case. I replaced the switch on mine a couple years ago.