Snowing here in VA now. I tried doing a search for the same topic and I cannot pinpoint my problem. A few days ago when an Alberta Clipper came down and gave us a couple of inches of snow, the expy started to fishtail everywhere, which tells me that the front tires are not spinning. I put the switch into 4HI, and nothing happens, 4LO, nothing. The 4x4 light does not come on either, and no clicking noise. I checked the fuses under the dash, and in the engine compartment, and those are fine. I checked the connections to the motor on the transfer case. I pulled the dash switch out, and tested the voltage. I'm not an electrician so I don't know what I'm looking for. I put a voltmeter to the wire harness, and one of the wires had 14 volts, with the voltmeter grounded to the black wire. Is the switch dead? Is there a way I can find out by jumping the wires on the connector to try to activate the switch? Thanks in advance.

-Mike

 

I have a 2000 exp and the same problem. I also checked the switch and I removed the 4x4 transfer case motor and could turn the gear manully but could not turn the motor. I took it into ford and spent the Hundred bucks so they could tell me what I had expected the 4x4 transfer case motor was toast. so I am now looking for a 4x4 motor. Good luck

 

Thanks for the reply. What triggers the dash light (4x4 and low range)? Is it the switch on the dash, or the acutal transfer case position? Does this motor also control the A4WD function, as the front tires are supposed to turn when the rears are spinning?

 

Can anyone shed anymore light to this? Sounds like my problem is the transfer case motor. But, what controls the TOD function? My back wheels spin freely in the snow/ice, and the fronts dont do anything. The switch is not working. Thanks in advance

99 Expedition 5.4 4x4 98k miles

 

maybe the relay is stuck. try tapping on the relay under the hood in the distribution box. next would be the motor on the xfer case. they tend to go bad when not used much. sometimes you can remove the motor and repair/clean it to get it working. i have seen pictorials on other forums that show how to clean it/refurbish it.


good luck

 

Does anyone know which relay it is in the distribution box? I'm not an electronics expert, so, how can I test the relay with a multi-meter? I'm hoping it's the relay since it's easy to get to, and whenever I have time to go under the truck it's been snowing(!!).

 

Your '99 should be same as my '00. The TOD relay and shift relay are a little tough to get to and takes about 30-45 minutes to get to. They are located right on top of the dash, almost above the radio. You have to remove the trim cover around the radio (turn the air vents inward and you can pull the panel straight out by grabbing inside the vent openings) unplug the connector for 4wd switch, remove the upper steering cover trim (4 clips, pull out gently towards you and also put gear selector to 1st gear as this makes access easier), pull out the headlight switch (you will see a small notch on the bottom that you can slip a screwdriver or similar tool into to pry out from the bottom--best to wrap a little tape on the blade to keep from damaging the trim) and disconnect the wires for it. Remove the instrument cluster finsh panel (6 screws) and disconnect the wires for the rear window defrost button (pedal adjust button also, if yours has this option). If memory serves me, you should now be able to see all of the screws (5) to get the upper dash/instrument cluster panel off and reveal the relays. I might have missed something but you should be able to see most of the hex screws as you go.

 

Is this the "GEM" module we're talking about, or are there other relays/module up there that i can bang around? Sound's like this is going to get expensive....

 

The GEM module is piggybacked to the rear of your interior fuse block and could be a possibility for your 4WD problem---I had to replace mine but got a used one from a salvage yard for $65 so wasn't too painful on the wallet. I would go back to the switch--you said you checked the voltage but these work on resistance values that communicate to the GEM. Pull the switch and check the ohm values with a multimeter. Connect the leads to the #2 and #3 terminals on the switch and then rotate it through the 3 settings. Your resistance values should be 3700-4100 for A4WD, 1040-1160 for 4 HI and between 340 - 380 for the 4 LO position. If the switch checks out and the shift motor is good, it's kind of pointing to the relays or (hopefully not) the GEM. Of course it could be wiring problems/ connections as well. If you do dig in to your dash to get to the relays, you can test these as well with your multimeter. It would probably be worth the $$$ to take it to a dealer and have them do the diagnostics with their scanner due to the complexity of the system---lots of places for problems to occur. You can spend lots of $$$$ replacing components and still not get to the root of the problem so spending a little at the dealer to troubleshoot can be cheaper in the long run---guess it depends on how much time and money you have to spend!!

 

Well, had a nice weekend so far. Put the expy on ramps and checked the connections and switch out. The switch works. I cleaned the connector from the harness to the transfer case motor, and gave it a good bang with a hammer a few times. Put it on the road and it worked!! (for a little while though). It would now click into 4HI, and I had the fronts and backs spinning. But now, I cannot get the light to turn off unless I turn the truck off, and back on. Then, it will go back into 4HI again when I switched to it. Sounds like the transfer case motor is starting to seize up, right?

 

Sounds like you are getting to the root of the problem--I didn't mention the shift motor because I thought you started here and ruled it out. The shift motor and switch are the normal culprits and where to start for troubleshooting. You might be able to pull the shift motor and tear it down for a good cleaning if it is not too far corroded and gone. They get a heavy duty exposure to the elements and road chemicals so they do take a lot of abuse. Be sure to mark the adjustment plate position relative to the housing if you do take it apart.
Ebay's a good place to pick up new ones for $100-$125 if you can't clean up your old one. You can also hot-wire the shift motor with the solid yellow and orange wires--release these from the plug connector and run a live lead to either the yellow or orange (ground the other lead). This will run the motor in either a clockwise or counter-clockwise movement and by reversing the wires you will reverse the direction so you can check the movement in both directions. Be sure to disconnect your hot wire when the shift motor hits the end of its run so that you don't burn up anything in the motor. If it moves fairly easily, it probably can just be cleaned up.