Esof - doa
Earlier this summer the dash lights for the “4X4” and “Low” started flashing on and off with the ESOF dash switch in the OFF position. No matter what I did with the ESOF switch the indicator lights keep turning on and off until they stopped in about 10 minutes or so. This happened as I was driving to work on a paved dry road at 60 MPH in June. The 4WD never kicked. I have driven ESOF long enough to “feel” the 4WD coming in and out at that speed and it never did go in.
<O

Now nothing works! No indicator lights, no locking in or out in high or low or anything.
<O

I have put the ohm meter to the contacts of the ESOF switch and it appears to be OK.
<O

I have checked the plug on the transfer case and it appears to be making contact.
<O

I replaced the transfer case motor last winter.
<O

Last week on a business trip to Michigan</ST1
all of a saddened the 4X4 light came on, stayed on for about three minutes and went out. At the time I was driving about 70 MPH or so on the interstate and did not notice any change that I normally feel as the 4X4 engages/disengages at that speed. <O

Also checked fuses and all appear to be good.
<O

Vacuum locking was working all of the past winter so I do not think that is the problem.
<O

So what’s up? Relays or something else?
<O

2001 F350, SD, 4X4, 7.3L PowerStroke, CrewCab, Longbed, six speed manual trans.
<O

Winter is coming and I just might needed the 4X4 soon!
<O

Thanks,
<O

Ron




