1997 Explorer XLT no 4WD low range

[backroads]

New to this website. I appreciate the valuable info from all of you to help solve problems on this vehicle.

Original problem: flashing 4WD lights on dash generated 4 trouble codes: P1850 (T case contact plate B ckt), P1854 (T case contact plate C ckt), P1866 (T case svc req'd), P1812 (4WD mode select switch ckt fault).

Attempted remedy #1: wrecking yard t case shift motor with everything cleaned up. Result: 4WD high range OK and dash lights do not flash now. 4WD low range not available (4WD light stays illuminated, but low range not showing on dash and still in high range)

Attempted remedy #2: new t case shift motor. T case selector rotates smoothly by hand. No change from #1 result above.

Attempted remedy #3: new dash mode select switch. No change from #1 result above.

Attempted remedy #4: new relay behind center of dash. No change from #1 result above.

Attempted remedy #5: new GEM put in behind center panel of dash. No change from #1 result above.

All of this work occurred over November and December. I am out of ideas and need some help from the group on what needs repair to get 4WD low range.
Thanks, Don (backroads)

 

[RangerFabWorks]

i know you probably have tried this, but put the truck in neutral. shift in 4high, then put it in gear, shift into neutral again, shift into 4low. shift to reverse, back up about a foot, then neutral, drive. it should shift into 4low. thats how i have to get mine into low.

if it hasnt been used in a while, then its just a little sticky.

and remember, anytime you shift out of 4wd, put the truck in reverse and back up a couple feet. this helps to disengage the front axle.

just cheap insurance