4 Wheel drive not working

Have 02 f250 7.3 auto trans, 4wd don't work have replaced just about everything, new switch, control motor on transfer case new module under dash, fuses and relays are good, what else is there, should I have power to the switch only power I have is for the light.

That's what ford garage told me code was, the trans esof motor, other garage told me code was module, still not getting answer I need, should I have power on switch in dash and where does that power come from

I have shift on the fly and when I turn on to 4 wheel drive light don't come on and 4 wheel drive don't work? I did all that even put new hubs and vac lines on but when I turn the switch I have no light and no 4 wheel drive. My lock outs work good its the transfer case that is not kicking in the switch has no light I have power to the motor on the transfer case but its not kicking in on and thank u for this help.

Thank u again for this help I am lost I just bought a new motor for the transfer case and I hope that's the problem if not its a costly very costly mistake lol
mike thank you but I was wondering if u had the wiring diagrams also cause its telling me to check all these wires and I have no clue where they are lol and again thank u for the help

Iam pretty sure everything is cause I hooked a tester up to it and I can make the 4 wheel drive engage well at least that's what the machine said lol and it shows the switch is working but the real weird thing is that when I moved it the other day it was actually in 4 low but the switch was not on I was thinking I did that with the tester I was wondering if there was a separate wiring harness to the motor on the transfer case I dont want to get a whole new wiring harness for the whole thing again thank u for ur help

Turn switch to 4 wheel and does not turn on

I have a 2001 f250 powerstroke and the fourwheel drive wont turn on when I turn the switch on no light or anything comes on

No I havent checked to see if it is getting power at the acutator, and I dont have an owners manual to see what fuse it would be. Thanks for the help

Make sure transmission is in neutral and wheels are straight ahead.

109,000 miles I was driving all day and the four wheel drive was working fine. I shifted out of four wheel drive & tried shifting back in & now it will not work.

It's electric shift and I'm not getting any power to it.

Electrical problem
1999 Ford F250 V8 Four Wheel Drive Automatic 100K miles

Turn on the head light switch the 4 wheel drive kicks out, while the windshield wipers do not work and the electric side windows do not work.

Turn off the head lights the 4 wheel drive kicks in cluncing, not working propersly, now
the windshield wipers work and the electric side windows work.

I have disconnected the axel for the 4 wheel drive,
still the things above happens.

The fuse box has taken water and there is some green in ther, however, I do not where I can buy a new one?

If that is my problem?

Ford f-250 1998 4x4 issue. Recently I had a new transmission put in. When I got the truck back we had electrical issues. Windows dont function, 4x4 is now not engaging? I brought the truck back and they will were unsucessful. What can I do, where do I start?