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So I am now certain as I can be of my measurements. The only edit would be that the high voltage is not quite 'battery voltage' but some output of slightly lesser potential from the TCCM or actuator. Here are some pics of my latest backprobing of the blk/wht signal wire from actuator to TCCM C2,B6

42mVDC in 2Hi, unlocked axles

11.51 VDC in A4WD, locked axles

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Also, looking at the schematics below, the 4x4 switch (encircled in green) is in 2x4 mode while the blk/wt wire seems to be floating at the actuator. Which makes sense. That's the reason for these 42mV at 2Hi. In A4WD or any other 4x4 mode, this wire will be switched to 12V at the actuator.
 

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Another question, guys. I believe that many people already bypassed the disconnect fork. I wonder if there any info on the long-term consequences of this mod. I think I would prefer to rebuild my disconnect every year than repair or replace the front differential.
 

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Sorry for reviving this old thread. I finally built and tested the small electrical circuit that emulates the operation of the actuator. The circuit works properly, there are no codes and the transitions from 2Hi to Auto and 4Hi are going smooth. Here are the links for the video of the device in action: part1 and part2. Sorry for the bad quality of the video.
 

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Hello, I'm sure this is going to sound random, but you seem very knowledgeable on this topic. I am using the front axle actuator for a different project that isn't powertrain related so i just have the small housing and actuator. can you tell me what each of the 4 wires need to "hot wire" the actuator and make it work from any 12v source? I have a power probe and can make a 5v signal also if necessary. Any help is much appreciated!!

Thank you!
Michael
 

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I was noodling around with one a few months ago. There is a 12 volts source, a ground, a control signal and an output signal. The output signal is not needed to operate the actuator but is used to report the status. Grounding the control wire activates the unit...

 

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Attached is the pinout of the actuator's connector. Black wire (terminal B) to -12V, brown wire (terminal D) to +12V. If the light blue wire (terminal A) is left floating (not connected to anything) or connected to +12V, the actuator is retracted, the discoinnect is disengaged, like in 2x4 mode. Ground this wire (conect to -12V) and the actuator will move and engage the disconnect (4x4 mode). Terminal C (black/white wire) is the feedback signal used to report the actuatopr status to to the transfer case control module: low (ground potential) in 2X4 mode, high (+12V) at 4X4 mode.
 

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Thank you guys more than you know! Like I said, I'm not using it for anything powertrain related, but It is the perfect device for another automotive product that I'm designing. When I'm done with the project and all the bugs are worked out I'll share it here. Another quick question; What rough diameter are the axle shafts themselves (not the splines) and are both sides of the 4x4 actuator the same axle splines or are they different? Thanks!
 

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Thanks a bunch, I'm using it as a shaft disconnect in a different automotive application. So I wired it the way you guys said, and when I ground the blue wire the actuator pushes out like it should, sounds like its under load (its not jamming the gears, they're engaged correctly) then slows to a stop. if I keep the blue wire grounded the actuator gets quite warm, then if I remove the blue wire from ground it will no longer return. when I try and get the actuator to move I can hear the switch inside the actuator click but no movement occurs. how long is the stroke on that thing anyway? I have a 10A fuse on each wire and nothing blew.
 

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Not sure about any "switch" in the actuator that could click. There is a slider attached to the mechanism that is the only switching going on in there. Double check your connections/terminals??

Here is a look inside...

 

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how long is the stroke on that thing anyway?

Here it is fully extended. Note the coil spring inside the "pusher" cylinder. If something is misaligned or otherwise stuck in the gears and fork assembly the coil spring allows for the actuator motor and related circuitry to still travel the full extent but not engage the disconnect. If the gears then move slightly to a properly aligned state the coil spring will then extend and move the shift fork etc to engage the gearing. When I disassembled my disconnect in 2014 I found a thrust washer that is supposed to be between the two gears had worn and slipped down to a position that blocked the travel of the shift fork and collar gear. My actuator still travelled the full distance and sent the signal back to the TCCM indicating it was engaged but in fact only the coil spring was compressed and the gearing was inhibited by the misplaced thrust washer.

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when I ground the blue wire the actuator pushes out like it should, sounds like its under load (its not jamming the gears, they're engaged correctly) then slows to a stop. if I keep the blue wire grounded the actuator gets quite warm

What is the status of the feedback signal wire at this point? Would it indicate full engagement to the TCCM if you were using one?
 

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Attached is the pinout of the actuator's connector. Black wire (terminal B) to -12V, brown wire (terminal D) to +12V. If the light blue wire (terminal A) is left floating (not connected to anything) or connected to +12V, the actuator is retracted, the discoinnect is disengaged, like in 2x4 mode. Ground this wire (conect to -12V) and the actuator will move and engage the disconnect (4x4 mode). Terminal C (black/white wire) is the feedback signal used to report the actuatopr status to to the transfer case control module: low (ground potential) in 2X4 mode, high (+12V) at 4X4 mode.
This is mostly to TJ, but anyone can answer ...

Can Terminal B actually be -12v?. That would imply a voltage differential of 24v between terminal B and terminal D.

In testing various other circuits on my TB or other vehicles I've never come across a -12v leg.
 

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The actuator would be out all the way. It just didnt seem to stop trying to move. it was under load and got hot so I disconnected it and now it wont do anything.
Here is a look inside. There is a slider/jumper that travels with the actuator, making contacts across several strips on the circuit board. Wonder if something got fried there...

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Can Terminal B actually be -12v?. That would imply a voltage differential of 24v between terminal B and terminal D.
Terminal B is a car's ground, the chassis. The terminal D must be 12V positive relative to the terminal B (2x4 mode), or grounded (4x4 mode). So, there is no 24V differential here. In my post #48 I mistakenly wrote "-12V"; I actually meant the ground potential (0V) here. I reverse engineered the actuator in order to make its emulator without moving parts (please see my post #45 above). The terminal D signal path is as follows: backward biased diode >> PNP transistor making a high side switch (please see the simplified diagram of this switch attached). When D is HIGH , the output of this high side switch is LOW and the actuator is disengaged. When D is LOW (grounded), the otput of the high side switch is HIGH and it engages the actuator.
 

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