4x4 Not Working - Question

[Alligator Wrangler]

Hello, TRS. I have a 2005 4x4 4.0 V6 Ranger with 167K miles, and I'm hoping someone can help me out with the 4x4. The 4wd selector switch is illuminated, but flipping it to 4Hi or 4Lo does nothing - there is no click or indicator light on the dash and 4wd does not engage. I tested the voltage on the switch and get about 4V at 2Hi, 3V at 4Hi, and 2V at 4Lo. The fuses all are fine.

I was thinking the transfer case control module was bad, but with ignition, the 4Low and 4x4 dash indicator lights do briefly flash one time, and then turn off. If the module was bad, would it be able to send those signals?

When I bought this truck, it didn't have a front driveshaft at all so I installed one from a scrap yard. This truck has pretty janky wiring in some areas (previous owners), and a mechanic working on an unrelated issue said he noticed that two of the wires on the transfer case were connected incorrectly (not sure which ones). He repaired the connection but the 4wd still didn't work. One of the 4wd fuses was blown at the time, and was replaced. (I'm not sure which one either...)

Do you think this is a transfer case control module issue, or does it sound like a wiring problem?

Thanks for any tips. Have a great day.

 

[PetroleumJunkie412]

My 2011 essentially does the same thing. Replaced motor and CM, no fix.

I'm guessing I have a wiring issue somewhere.

 

[RonD]

In 2001 and up Rangers with 4WD have a 4x4CM, these were prone to failue
They have two Relays inside, when you select a different setting on the Dash switch you should HEAR the 4x4CM "click" as it closes one of the relays
IF..........the shift motor doesn't move when 4x4CM closes a relay the 4x4CM will flash the 4WD lights rapidly indicating a problem

The dash switch rarely breaks, its just 3 resistors with 2 wires
4x4CM sends it 5volts on 1 wire
If 4x4CM gets back 4volts on the other wire then switch is in 2WD setting, 3volts=4High, 2volts=4Low
Simple setup for switch

The shift motor is a 12vDC motor with 2 wires, works the same as power window motor, send it 12v on one wire and Ground on the other and motors turns clockwise, reverse it, ground and 12v and motor turns counter clockwise, window up/window down, shift to 4high/shift back to 2WD

So the 2 relays in the 4x4CM are for shift motor, one relay for each wire, each wire is grounded when it's relay is off
So the 4x4CM only needs to activate 1 relay, which unGrounds that wire and connects it to 12v, other wire is already grounded

The 5 other wires on the shift motor are position sensors/contacts, they are either open or closed depending on the position of the wheel under the plate, which is connected to the transfer case shift rod
As the Motor's worm gear turns the plate, and shift rod, the contacts change, open and close, each position, 2WD, 4H and 4L have a unique contact open/closed sequence
This is how the 4x4CM knows what way to turn the motor and when to stop it, when contacts match dash switch setting


If you don't HEAR a relay "click" then 4x4CM is most likely issue
As for testing, both motor wires should test as grounds when you unplug connector, if not then also 4x4CM issue

Pull the shift motor and test it at battery, 12v and ground, there is a STOP PEG inside so it may only turn one way at first, but then will turn back the other way until it hits the STOP again, its a physical limiter not a sensor or switch

 

[Josh B]

Not complicated so much AW, if you've ever repaired a starter you have done more than these things take.
Hek, it may just need a good dusting
I got lazy or maybe in a hurry on mine 16 years ago and bought a new one for $100.00 and it is in it to this day. And the original? It is still sitting in the box the other one came in, less the dust it needed blown off, otherwise it's ready to go

 

[DILLARD000]

Yep, 4x4ConMod is likely bad;
If 4x4 system is not exercised briefly, driven short distance monthly in each mode 2WHi~4WHi~4WLo,
4x4ShiftMotor tends to get crusty, intermittent or just stops working.
Can remove 4x4ShiftMotor & turn TCase stem with ViceGrips back to 2WHi if stuck in 4WHi\4WLo.
Can also test 4x4ShiftMotor with it removed from TCase (4 Bolts) & still plugged into harness.
If Motor rotates thru 2WHi~4WHi~4WLo & back properly, then its likely getting weak\failing & needs to be replaced.
If Motor does not rotate, 4x4ConMod is likely failed; 4x4ControlSwitch on dash is a simple item, least likely to fail.
If wiring is jumbled, best to get 4x4 wiring diagram for your Year+Model & tediously work thru & confirm all connections+wiring+parts.
Click here for more info on this 1354 4x4TCase+Controls.

 

[Alligator Wrangler]

Thanks everyone. I ordered a new motorcraft control module and will update when I swap that in. If it seems to work, I'll most likely also get a new shift motor too to preempt any problems.

 

[00t444e]

Swap to a manual shift transfer case.

 

[CorbinsRanger]

Swap to a manual shift transfer case.

 

[00t444e]

Yeah like that ^^^

 

[Alligator Wrangler]

That's awesome. Might have to do that someday.

 

[CorbinsRanger]

That's awesome. Might have to do that someday.

Youn would need a time machine and go back to 02 or 03....

 

[Alligator Wrangler]

Replacing the control module did not work - it's still the same situation: 4x4 icons light up during ignition, and nothing happens when the switch turns. I don't feel like meticulously going through the wiring to figure out what butchery the previous owners committed, so I'll probably take it to a shop.

 

[PetroleumJunkie412]

Replacing the control module did not work - it's still the same situation: 4x4 icons light up during ignition, and nothing happens when the switch turns. I don't feel like meticulously going through the wiring to figure out what butchery the previous owners committed, so I'll probably take it to a shop.

Let me know what the outcome of this is. I still need to track my issue down, but knowing familiar places to look may help.

 

[Josh B]

Replacing the control module did not work - it's still the same situation: 4x4 icons light up during ignition, and nothing happens when the switch turns. I don't feel like meticulously going through the wiring to figure out what butchery the previous owners committed, so I'll probably take it to a shop.

Have you considered pulling it off, plugging it in, laying it in a spot where you can watch it from the cab, run a ground from the transfer case to the motor, and flip the switch to see what it does, if anything. That could tell you volumes, or maybe nothing, but it's a start.
Anything beats paying $1,000.00 or more for a $0.25 washer they patched it with ( I have heard of that very thing hapenning)

 

[DILLARD000]

Dont need the ground wire, its already in the harness. Do need a friend in the drivers seat to operate the switch with the engine idling, trans in neutral, foot on brake, while you watch the 4x4Motor for rotation. Besure to have park brake engaged, wheels chocked, jackstands for safety. Also be sure to use correct ConMod, 2001-2005 version only.