First off, I assume you ARE stopped with the transmission in neutral and your foot on the brake pedal when you attempt to shift into/out of 4WD LO?
Assure that all 4 fuses controlling the GEM are good. They are #'s 9,10,20,28 in the fuse box under the dash. Also #6 in the nuder hood fuse box.
The electronic module,located behind the glove compartment, controls the operation of the transfer case in response to inputs from the electric shift motor, 4x4 mode switch, Clutch Pedal Position switch, Brake Pedal Position switch, Digital Transmission Range sensor, throttle position output from the PCM, front and rear Output Shaft Speed sensors, and the VSS. Most malfunctions are caused by wiring issues, most common being bad connections in the connectors. Open the glove box, push in on the sides to allow it to drop down and disconnect/reconnect the module connections several times, see if it works properly. Check for poor connections at the shift motor wiring, making sure the ground wire is still connected. If all else fails you can remove the motor and manually shift it back into 2WD. If you don't have an owners manual to identify the fuse locations you can view/download one here: http://www.motorcraftservice.com/pub.../00expog1e.pdf
Thank you so much !
That is exactly what I was looking for.
This is the 1st. 4x4 that I have ever had, It was given to me because it had a bad motor, I replaced the motor, but when I got it running, it is in 4x4 lo.
I'm sure your info will help.