3RD Time... Diff Lock Stuck On (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

You may want to create a separate post write-up and become MUD famous
 
Glad you got it working! 🍺

Since the ECU relays started clicking once you manually moved the actuator it sounds like the motor limit switch was in limbo and there was no ground path for the ECU relays to move the motor either direction.
7F292D7B-A882-430C-AB28-42F6263D9A8D.jpeg
 
You may want to create a separate post write-up and become MUD famous
All righty, so here is my post-resolution summary, observations, findings, for repairing the CDL actuator. I hope this helps others in the future:

Symptoms:
Center Differential Lock will enable, but not turn off. The Diff Lock symbol and VSC lights will illuminate on the cluster but fail to turn off once the switch is depressed.

The first (2) times this happened, I drove the vehicle with the CDL button turned off (you can tell because of the position of the switch is out) and could hear at normal speeds of approx. 10-35 MPH that the CDL relay under the glovebox is clicking and *trying* to turn off.

During this time, I was able to disable the CDL by hitting a pot-hole, a slanted driveway, or just going on a short drive through the neighborhood making wide turns. I shortly after stopped using the CDL function.

Once I accidentally enabled the CDL for the 3rd time, it would not turn off no matter what I tried. I tried to drive forward/backwards slowly, tried this in low gear, tried repeatedly to click the CDL button, raise a drive wheel onto a curb, figure 8's in gravel forwards/backwards, checked all the fuses in the engine bay and driver kick panel area, coasting in neutral, and replacing the sensor located on the transfer case.

At this point, with the CDL not functioning, I observed that pressing the switch did not make any relay noises under the glove box AND the relay did not flutter as I drove around.

Testing:
To test whether the switch is bad I would refer you to post #21 by @Ayune (thank you!)

To check if the Transfer Indicator Switch is working and not sending a false signal - I suppose you can either unplug the sensor or switch it out with a replacement. NAPA part # NS6421 - Beck/Arnley part # 2011788 - Autozone part # JA449.

Check the fuses and relays.

Actuator Removal:
At this point, I have exhausted all efforts and decided to just remove the actuator and see if there was any evidence of malfunction or damage. I was expecting to see a broken arm or lots of mud/dirt.

There are (2) ways to remove the actuator:
Option 1 - (8) bolts to the transfer case sub-frame and drop the transfer case 1" - 2" for easier access and for those with bigger hands.

Option 2 - Don't drop the TC sub-frame and still get the actuator out with the same amount of knuckle busting, just less room.

Both options only require a short 12mm socket and ratchet.

There are just (4) bolts to the actuator, a wiring harness and vacuum line. Removal is accessed from the passenger side underneath the vehicle at the back side of the transfer case at the very top, by the drive shaft.

Here is the unit once removed from the transfer case:

IMG_8391.jpg


Here is the unit with the gear casing open:

IMG_8393.jpg


Some observations I made were that the (3) metal pins shown in the image above were dirty, they had some browning on the tips of the contacts and also on the metal maze area of the other side. I wiped all the grease off from the metal contacts and re-installed the actuator.

I was VERY enthusiastic, all of a sudden the CDL switch on the dash was making the trademark "clicking" noise every time it was pressed from under the glovebox.

NOTE: Test the unit before fully installing, connect the wiring harness and vacuum lines, put the key into ON position and listen/watch for the motor to engage when pressing the CDL button.

Unfortunately, my motor was not turning the gear UNTIL I persuaded it with my fingers. Almost like it was not getting enough power from the motor. Bummer.

I removed the actuator another time and took it apart again, I sat at my work bench staring at the electric motor side of the actuator for a good few hours until I realized I had done one thing wrong when re-assembling it.

When I originally dissembled the electrical motor coil side of the actuator, I didn't see how the brushes and springs were installed. It all fell out once the case was removed.

IMG_8398.JPG


When re-installing, you'll need a second set of hands. The spring, as shown in the image above, which is resting on the coil, was missing the brushes. The brushes are the little black cubes connected by an electrical wire.

The spring needs to be pressed in on both sides, and then the brushes needs to be installed on top of them, holding them down while inserting the coil rod.

Once I had assembled the electrical coil CORRECTLY with the gear side of the actuator cleaned up, it worked FLAWLESSLY. The actuator does not struggle to engage/disengage and works as if it was brand new.

I hope this helps anyone that has had this problem, the actuator is $1200 from the dealer and $430 online from a second hand dealer, problem being that it ships from the UK.
 
Last edited:

Users who are viewing this thread

Back
Top Bottom