94 Explorer 4WD issue

[honestjerry]

Hi all, trying to get some help with my 4WD system. I read the stickie, did some searches, but I'm still not clear on next steps.

Symptom - no lights on dash for 4WD or Low. Hubs clicking/ whining as if the 4wd is engaged. (yup, the auto hubs need some attention too - got that)

Troubleshooting - module self test OK, but no clicking when dash switch is pushed.

Questions -
1) what do I test on the switch? Voltage where and when?
2) how do I get the switch out of the dash? (don't want to break any 20 yo plastic!)
3) could it be something else? (shift motor?)

Thanks,

Jerry

 

[ranger-93]

Need to check the front driveshaft after attempting to put it in 4 wheel drive to make sure it isn't in 4 wheel drive and the lights just aren't working. Not very likely imo but still possible. If this checks out have someone push the 4 wheel drive button while you tap on the shift motor with a hammer, not to hard though. Tap it like you would a starter when it starts to go out. Iv had two problems with shift motors on two different trucks so my luck has always been the motor. There is a way to rebuild the motor (also found on here using search button) but I've not had luck either time and just bought another motor like 70 bucks and its worked since than. Let us know your findings. And welcome to the forum.


Edit: after re reading your post I'm thinking switch since module self tested ok but no clicking. Search for testing the switch, I'm sure its somewhere on the forum.

 

[firefighter 20]

I had this same problem it was just the connection on the plastic connecter that goes to the shift motor. I would make sure u are getting a good connection

 

[jmdirk]

I would start with checking and cleaning the connection at the transfer case as recommended by firefighter. I've had the same issue in the past.

I think the next step would be the motor itself. There's a plastic bushing on a post the limits the rotation. When that plastic bit falls apart the, the position indicator gets lost and the shift module has no idea what gear the transfer case is in. So the shift module tests out okay, but doesn't report anything to the switches on the dash

 

[honestjerry]

I worked on it today. the motor runs ok when powered, nothing is stuck and actually the position bushing was just cracked but still intact. I replaced it as some others have talked about in other posts but no change. The switch appears to be ok. I checked continuity on the wires from the switch to the control module, no breaks, all seems well.
The switch is getting 12v, the ground to the switch is good. All the connections under the truck are clean and in good condition.

I did notice that after putting everything back together, I must have had the position indicator off just a tad. When I turned the ignition switch on, the 4x4 lights were on. I pushed the button, the motor ran just a bit, the light went out and now it's back to the way it was.

I guess it's either the motor assembly or the contoller.

Seems like a cable and a lever would be a hell of a lot easier!!!!

 

[honestjerry]

Finally got back to this. The culprit was the 4wd control module. The reason for the failure was a leaking quarter glass! Pulled it apart today after a hard rain and found water in and on the module. $10 U pull it controller and reseal the window unit and all is well!

As a note, the self test was good on the old module. I guess that is not always a good check.

Thanks for the help!

 

[DeRocha]

Finally got back to this. The culprit was the 4wd control module. The reason for the failure was a leaking quarter glass! Pulled it apart today after a hard rain and found water in and on the module. $10 U pull it controller and reseal the window unit and all is well!

As a note, the self test was good on the old module. I guess that is not always a good check.

Thanks for the help!

Glad to hear you found the issue and got 4x4 back in working order. That is weird about the 4x4 controller test passing when it's been fubar'd by water.