Okay my 4wd went out 150k miles ago. I got this truck handed to me from my dad cause he bought an 04. Im rebuilding this truck under my own wallet and the ford dealership wanted $160 for a DIAGNOSTIC! So i bought new fuses, and redid my entire fuse panel inside and out with fresh, proper fuses just not the big fuses (im pulling a blank on what thats called) and my 4wd esof switch wont even glow, the switch is absolutely dead. I have no idea whatd cause it to be this. One dude from oreileys said it could be a gem module. I know nothing about electronics, can anyone help me? Has anyone had this issue as well?

 

If you paid dealer they would read you the code to be sure.

Its likely the shift motor. When it loses position indication, the system shuts down.
Its also very common. Easy fix.

 

I like the sound of that! I still bury my *** end trying to bog or go in the sand river beds😂 (i inserted pics of my struggle lol) Are you knowledgable on how to reset or fix this circumstance. Ill gladely give it a shot in high hopes.



2wd mud bog😂



And my dumbass thought 2wd with deflated rears would be fine... i need my 4wd fixed😂

 

They run about $85 on amazon. easy. 3 x 10 mm bolts and a wire harness. You have to probably move a wire pin to new harness or splice wire. Takes 10 min.

 

Ill youtube right now, thanks bud! Hopefully thats the issue

 

Clean truck man, I remember my off-road days. Mud always ends up in my mouth when I work underneath my truck now haha

 

I just went through this. It was the relay in the dash in my case and I ended up sending the shift motor back. While I was waiting for my shift motor to arrive I fiddled around with it because it would shift some times.

Before replacing the motor, verify that you hear a click from the relay in the dash when you turn the selection switch between 2wd and 4hi and back. If you don't, there probably is no power getting to the shift motor to begin with. Then your problem could be the relay, or the selection switch, but from what I gather the selection switch rarely goes bad.

If you do hear a click from the relay, then it's possibly the shift motor, and you can check whether the shift motor gets power by using a test light on the yellow and orange wires while someone else is turning the selection switch between 2wd and 4hi. Use a standard ~5 dollar test light that lights up to indicate power, clip the jaw end to the frame or other ground near the shift motor so you can reach the motor wires with the tester, gently poke the sharp test light end into the yellow wire, through the plastic cover, the sharp end of the test light must touch the copper in the wire. Have a buddy turn the key to ON, or start and turn the selection switch to 4hi and back, the light should light up if there's power. Do the same for the orange wire cuz I don't remember which color is which Test this on the wires on both sides of the harness. If it all lights up, you have power to the motor and the motor is probably bad.

Toward the bottom of this link is info if it seems like the relay is bad and needs to be replaced or fixed. There's also a link in the last post on how to remove the dash to get the relay out. It looks harder than it is, took me 10 minutes.
https://www.f150forum.com/f6/1999-f1...351458/index2/

 

I could be mistaken, but I don't remember relay working with bad shift motor. It's not actually the motor, it's the inside electronics and positioner that usually fail. System totally locks up, the self test fails on starting engine and it's completely deactivated by gem.

If the motor failed, result would be different . It would try, but nothing would happen.