02 Explorer 4x4 won't engage & lights stays OFF

[mac999993]

I've read many many threads regarding the Explorere Transfer Case Shift motor issues, but haven't found one which addresses the condition when you push the 4x4 High or 4x4 Low button and the Light remains OFF - particulary for an 02 Explorer. When I press any of the 4x4 dash buttons (Hi, Low, Auto), nothing happens - No noise, no clicking, no light. I'm thinking it must be a disccnected wire harness or loose wire somewhere... Read below why..

Background:
In short, my son recently backed my 02 Explorer XLT over top of my neighbors freshly cut hedges... Don't ask!

I had to have a tow truck to have it removed.. the bushed actually lifted the truck off of the wheels enough to limit traction, and I couldn't hack my neighbors bushes completly down..

After the tow truck removed the truck from off the hedges, I noticed two things:
1) The ABS light came on - I found a disconnected wire harness from the rear speed sensor on the rear differntial. I reconnected the wire harness and that problem went away.

2) The 4x4 no longer works - Can't figure out the problem YET -- HELP! I looked around the 4x4 transfer case to see if the wire harness had been damaged on disconnected.. NOPE. I've tried to locate a diagnostic procedure to help me locate either something damaged or, more likely, a disconnected wire/harness. I figure that it is most likely a loose wire/harness since nothing happens when I press any of the buttons. Any Ideas? How can I troubleshoot - continuity tests, trace wiring for breaks, disconnects, etc. Hint: The bushes definitely were rubbing hard along the entire undercarriage during the tow truck removal process.. All I could do was GRIMACE!

Also, I presume that the 4x4 control module located behind the glove box (unlike the earlier generation Explorers which is located in the left rear panel by the jack). Is there a white button test on this generation 4x4 control module?

I would appreciate any help.. Thanks.

 

[BWilliams]

Did the 4x4 work before this... incident? Or did you just notice it now? I would think that if you had any other damage to the undercarriage wiring harnesses, you'd be getting fault lights, not just zero response.

I would suspect that it's the 4x4CM, like you mentioned -- they're pretty much destined to fail in the early 3rd-gens.

The 4x4CM is indeed behind the glove box.. just drop the box, and there are a couple screws that hold it in.. pull it out, new unit, should be good to go. The updated unit's part # is 1L2Z-7E453-AH.

Good luck!

 

[mac999993]

Did the 4x4 work before this... incident? Or did you just notice it now? I would think that if you had any other damage to the undercarriage wiring harnesses, you'd be getting fault lights, not just zero response.

I would suspect that it's the 4x4CM, like you mentioned -- they're pretty much destined to fail in the early 3rd-gens.

The 4x4CM is indeed behind the glove box.. just drop the box, and there are a couple screws that hold it in.. pull it out, new unit, should be good to go. The updated unit's part # is 1L2Z-7E453-AH.

Good luck!

Thanks Brad..

The 4x4 worked fine before the incident. In fact, both Hi and Lo engaged when I initially tried to drive it back off of the hedges... Something must have happened while the tow truck pulled it off of the hedges... That is why I was thinking it would be very coindicental for the CM or anything else to fail as a result of the tow truck taking it off of the hedges... and why I suspect that a wire/harness became disconnected from the hedge pulling underneith while they pulled it off. I just can't locate anything loose ot disconnected. Maybe something did fail... I don't know. I'd like to troubleshoot before replacing parts.

I'm concerned about this too because we are getting high vibes while driving now... it feels as though 4x4 is engaged but it doesn't indicate that it is On.

I may have left the 4x4 on before the tow truck removed it, then during the removal, perhaps a wire became disconnected, and now it is stuck on.. Sound possible?

 

[BWilliams]

and why I suspect that a wire/harness became disconnected from the hedge pulling underneith while they pulled it off. I just can't locate anything loose ot disconnected. Maybe something did fail... I don't know. I'd like to troubleshoot before replacing parts.

I'm concerned about this too because we are getting high vibes while driving now... it feels as though 4x4 is engaged but it doesn't indicate that it is On.

I may have left the 4x4 on before the tow truck removed it, then during the removal, perhaps a wire became disconnected, and now it is stuck on.. Sound possible?

I was trying to think of it as you just didn't notice the 4x4 was inop. earlier, until you just tried it.

If i had to guess knowing that it was on when you were hung up on the bushes, I would say that the harness to the transfer case shift motor got pulled out. That would keep it engaged in 4x4, and I don't believe that it would show it on the dash without the harness to the motor plugged in.

If you have to drive it before you can get under there to try and fix it... try to keep the speed to below 45MPH. That's Ford's recommended maximum speed when 4x4 is engaged -- I'm assuming that it's to keep the temps low in the TC.

Good luck!

 

[mac999993]

I was trying to think of it as you just didn't notice the 4x4 was inop. earlier, until you just tried it.

If i had to guess knowing that it was on when you were hung up on the bushes, I would say that the harness to the transfer case shift motor got pulled out. That would keep it engaged in 4x4, and I don't believe that it would show it on the dash without the harness to the motor plugged in.

If you have to drive it before you can get under there to try and fix it... try to keep the speed to below 45MPH. That's Ford's recommended maximum speed when 4x4 is engaged -- I'm assuming that it's to keep the temps low in the TC.

Good luck!

I checked the wire harness to the TC, and it looks perfectly fine. Are there any links that describe a troublehoot procedure for the Gen 3 4x4's?

 

[mac999993]

Check this link out: http://www.explorerforum.com/forums/showthread.php?t=163694&highlight=4x4+troubleshoot&page=4

Beware 2002 Explorer Owners (and maybe others)... If you disconnect your battery, you may/will create a failure of the 4x4 Control Module (CM), the black box behind your glove box.. That's good 'ole Ford for ya!

Turns out that I disconnected my battery in the process of repapiring the disconencted ABS speed sensor in the rear differential, and caused the CM to fail (At least, I'm pretty confident that it is failed, given what I read in the above thread).. I'll report back for sure, after I replace the CM.

 

[cmajor]

How do you change a battery then?

 

[joseg52]

i have a 2001 ford explorer sports im having problems with my four wheel drive engaging not even the switch lights come on showing engagement. i checked two fuses they were good. i found the 4x4cm and found power going in but none exiting. does that end my troubleshoting?

 

[joseg52]

help

i have a 2001 ford explorer sports im having problems with my four wheel drive engaging not even the switch lights come on showing engagement. i checked two fuses they were good. i found the 4x4cm and found power going in but none exiting. does that end my troubleshoting?