I have a 2002 f350 7.3 The 4x4 high was stuck last week afer using in some snow. I was in 4-low and went to 4 high and it never went to 2wd after tha I checked he fuses and all are good. I have a new motor and installed it today. The shaft was suck and really took a good twis o get it out of 4 high after removing the old motor. I rotated it back and forth quite a few times and lubed i up good. I reinstalled the new motor also. So now it still does no work. Is ther any relays hat i need o check? Maybe the burned up when he motor refused to shift it to 2wd. I checked the 30 amp maxi fuse with test ligh today and i is good. I really dont know where else to check. thanks for you help.. Jeff

 

There are 2 ESOF relays. Bottom right of this diagram shows the Low to High Relay and the High to Low Relay in auxilary relay box 3. I have no idea where the aux relay box 3 is. This is for a 2003 but should be the same for 2002.

 

Its the same for an '02. Oh yes indeed.

 

So where is "auxilary relay box 3" and the ESOF relays? Probably tucked up underneath the dash.

Edit : Found out it's underhood like my '99.

 

Ok, update in my 4WD problem. I took truck to dealer to put in the new module that is behind the glove box. They put it in and the the 4wd still does not go to 2wd. The dealer said it works when the computer is hooked up to it and operates it from that but does not work on its own. So the dealer mech sent a note to ford to ask for the fix. Anyone ever hear of theis problem? thanks Jeff

 

If the mechanic can use his test equipment to make it operate then I would think the problem would be the selector switch.

 

The final result is in.. The module replacement did not fix the original problem either. Dealer replace the module, told me the truck will not go to 2wd. I told them that is why i bought it her in the first place. They had to send a note to ford for help. So to go back a month, i had a mouse under the hood for maybe 2 days because i saw nuts over the ac cover under the hood. I then put in 2 new paks of Fresh Cab (rodent repellent) in the battery compartment blankets on each side of the motor. The mouse was gone the next day and since then. I checked for chewed wires etc but didnt see any damage anyplace. One week after this happened is when I went to use the 4wd and had the problem. I didnt think of it at the time that this could be the cause. So dealer calls me and says a wire on the overlay to the module was chewed causing the 4wd not to go to 2wd. It was the blue and white wire. they made a jumper for me and fixed it that way rather than pay for new harness etc. So now all is good. (except the cost to figure it out. ) What a fiasco this was... all from a mouse.... thanks for all the help here jeff

 

Glad your problem is resolved and thanks for posting the fix.