Hi, I have a 2000 F-150 auto with 4 wheel drive switch on dash. Sometimes it will not go into 4 wheel drive, doesn't matter whether it's moving or stopped. When it does work you can hear the relays under the dash clicking, and when it doesn't work those relays don't click. If I disconect the battery and then hook it back up it will always start to work again. Has anyone had problems with the generic electronoic module (GEM) ? Any input would be greatly appreciated.
Thanks in advance, Rick

 

Had a smilar problem with 02 Ranger 4X4. Noticed that it would'nt work when the cab was cold. Once it warmed up inside 4WD worked fine. Ended up swapping out the 4WD control module. Works all the time now.

 

I have the exact same issue. Used to work in warm weather then quit all together. Turn the switch, no lights, no clicking, no clunck, nada.

Took it to the shop, the shop talked to FORD and they said to replace the same GEM switch ($280) and only FORD could program the thing (add $100) and it did not fix it. Still nothing...plus about 5-7 hours of labor charges, so far...

Really ticks me off. Any definative answers to fix this???

 

I had the same problem with my 01 supercrew. There is a vaccuum diaphragm on the transfer case towards the front of the truck that gets moisture in it and freezes. It's a few inches round and it has a vaccuum line that goes to it. I took mine off and set it upside down infront of a heater for about an hour and then operate it by hand and it releases the moisture. If you can't find it, let me know and I'll try to get a pic of it.