I bought my '06 Sport 4x4 4.0L Auto about 7 months ago. At 69k miles it had a timing chain tensioner failure and busted the valve cover. Got a new engine in it and finally able to drive it as of Christmas. Everything works as it should except it doesn't go into 4Low.

I've read quite a few threads on here and much of RonD's replies. I am doing the stopped, foot on the brake, trans in N or P. Move **** to 4high, I hear a click behind the dash, you can here the transfer case motor shift (when the truck is off) the light on the dash comes on and it's obvious on the lift that all four wheels spin when the truck is in the air and I release the brake a little. If I then try to move the **** to 4low, I get nothing. I can leave it there for a minute and nothing. All 4x4 related fuses have been check under the hood and under the dash.

This leads me to believe either the transfer case control module is bad or the transfer case shift motor is bad. I have already removed the transfer case motor and used pliers to manual shift the transfer case from 2wd, 4high and 4low, nothing seems to hang up. Should I try the transfer case shift motor servicing as is found on the explorer forum? Or buy a new control module?

Thanks,
Jesse

 

And no flashing 4x4 lights?

When you select 4low from 4high does the 4high light change, does it go off?

The 4x4 system is pretty simple overall just the 3 parts
switch on the dash
4X4 module
Shift motor

The switch on the dash has 3 resistors
The 4x4 module sends it a fixed voltage, 5volts I think
If module gets back 4 volts then it shifts to 2WD, 3volts 4high, 2 volts 4low, just made the voltages up, never tested them
So with key on the module knows what the switch position is all the time
On the shift motor are 5 contacts, the 4x4 module knows each contact pattern for 2WD position, 4high position and 4 low position, and it moves the shift motor to match pattern selected by switch

For 4low the 4x4 module needs a 12volt signal from fuse #32, 5amp, on pin12, brake pedal switch, nothing to do with brake light 12v power, its a separate switch that Grounds pin12 when brake pedal is up, and then sends 12v to pin 12 when brake pedal is down

Transmission switch(DTR) Grounds pin16 on 4x4 module when transmission is in Park or Neutral, in 2006 I think it can only be in Neutral, Park won't work

Could be 4x4 module issue, they are a known failure point

And you can test the switch at the 4x4 module once its unplugged
Pin 5 on one connector will be a White/light blue stripe wire, that's voltage OUT to the 4x4 switch
On the other connector pin1 is a yellow/light blue wire , voltage return

Use an OHM Meter between those 2 wires and move the switch to its 3 positions, should show different resistance on each position, if 4high and 4low are same resistance then replace switch
What the exact resistance is, I don't know, if you want to post results here that would be great
But we know at least 2 of the resistors are good, since 2WD and 4high work

You can shift into 4high while in gear and driving under 55MPH, its called "shift on the fly", and you can shift back to 2WD in the same manner
4Low does require 0MPH on speedometer, foot on the brake and Neutral on trans shifter, and same to shift out of 4low to 4high or 2WD

 

With the snow coming tomorrow I'll be in my warm garage investigating. Thanks for the reply. I forgot to add to my original post that when I start the truck both 4high and 4low lights light up for a second. I do not get any flashing lights, 4x4, srs, cel etc.

I'll try what you described here. I was wondering if there could be a different brake switch as I did check to make sure the brake lights were working. Another thing I checked was that the shifter was reading correctly, put it in R and the reverse lights came on. I've read where sometimes the sensor on the side of the transmission can get off and then the truck doesn't think it's in N when it actually is.

 

Yes, both lights coming on is normal, its a "Bulb Test", most dash lights have that test with key on

You have an HEC instrument cluster in a 2006 Ranger(2004 and up Rangers)

Google: HEC test mode

Some neat stuff, probably not helpful for this but still neat stuff, lol


The brake light switch should have 4 or 5 wires connected, and there are two separate switches inside, one is just for brake lights, the other is more like a sensor and goes to computer and 4x4 module, this sensor is a Ground when brake pedal is up, this confirms it is working to the computer and 4x4 module, you will get a code if the 'sensor' doesn't ground, then it sends our 12volts from fuse #32(check this fuse) to computer and 4x4 module when brake pedal is down
It also activates the Shift interlock, allowing you to shift out of Park, but I am not 100% sure if the brake light power does that or fuse #32 power

 

See above in red for my response. I could try cleaning the transfercase shift motor next. Also wondering about the 4x4CM not knowing if the shift selector is in neutral.

Thanks,
Jesse

 

Very good testing

Looks to be a Red/white wire on pin 16 and it is a Ground when DTR sensor is in Neutral, from below diagram

Here is the wiring diagram for 2006 Ranger 4WD system

 

Thanks for the diagram, that should help the next time I have the radio out for testing the 4x4 control module. I did take the transfer case motor off and was going to clean it up per the explorerforums write up but once I had it pull from the transfer case and on my work bench I ended up snapping all 3 screws that secure the plastic cover. The plastic cover was also so corroded in that I broke it upon removal. I determined at this point I would just sacrifice the money and but a new motor and cross my fingers that was the problem (in the back of my head I felt it wasn't the problem). After putting the new motor on it is still doing the same. Will go into 4x4 just fine but will not go into 4x4 low. I will be pulling the radio out in the next week or two and testing to make sure the 4x4 control module knows that the gear select is in N. After that all that's left is to replace the control module.

 

A week or two turned into 10 months. I picked up a boat shortly after my last post that needed the engine pulled and rebuilt. In-laws got me a reverse cam for Christmas and while installing it on the lift I decided it was a good time to look into this. I referenced the diagram and first thing i checked was the neutral postion circuit. Sure enough it wasnt getting grounded. Went under the truck to check for continuity and immediately noticed the red/white strip wire was broken at the shift position sensor on the side of the trans. I have 4x4 low now! Pretty pumped.

 

Good work

And thanks for the update and the FIX