My girlfriend just bought a 2000 f250. Automatic trans with the auto 4wd. It has manual hubs but the switch on the dash when you turn it to 4 hi or 4 lo does nothing. No light on the dash no 4wd engagement nothing. All the fuses are good relays seem fine to me swapped them no difference. Got under the truck and unplugged the connector on the shift motor put my test light on it had her turn the switch back and forth between 2 and 4 hi and lo no light. Tells me no power to the tcase. Any suggestions? Thanks!!

 

Is the solenoid on the passenger side fender plugged in?

 

Yeah. Double checked that last night actually. I had found some damaged wires on the cross member by the tranny but i fixed them all and still same thing.

 

The vacuum solenoid on the passenger fender just locks and unlocks the hubs, the transfer case motor should still shift regardless of the hubs, The light on the dash wont go on intill the transfer case switches, you cant test for power at the motor with it unplugged. you have to have it plugged in then hit the switch and remember it's not a wiper motor the spins 360, it switches between power and ground to turn the motor clockwise and anticlockwise. If I had to guess I would say the motor, after you checked all the fuses under the hood and dash. There quit common.

 

If I unplug the connector and put a test light between the two pins on the connector shouldn't the light come on for a second or so while someone turns the switch. I know it won't stay lit but it should flicker or come on for a second as long as the circuit is complete with a test light shouldn't it?