Manually unlock stuck CDL help! (1 Viewer)

[jcolvin]

Ok, my CDL is stuck locked and no amount of driving forwards/backwards/sideways/upside down will disengage it. I'm thinking that likely the actuator is toast (as in https://forum.ih8mud.com/showthread.php?p=782052).

Before I go about dropping the transfer case and pulling that bast*rd off, is there any way to manually unlock it? If I remove the cover plate on the rear of the transfer case, is there anything in there I can jimmy to unlock the diff (so I can drive around in the meantime with the diff unlocked while I get ready for the PITA of removing the actuator)?

Couldn't find anything in the archives re. this......

 

[Gumby]

You can pull the four bolts off of the top of the actuator and remove the motor. The bolts are kinda hard to get to, but not bad. Three are easy to see. The fourth is about 2 o'clock and is up on a ledge so it's longer than the others.

The seal between the actuator and the transfer will be tight. You might need to tap it a bit.

Once the motor is out there will be a gear set into the top of the case. It might come out with the motor. Drop that gear back into it's hole so it engages the gear down in the case. Turn it clockwise to disengage the lock, IIRC.

I might be able to scare up some pics.


You can also pull your front driveshaft and drive around with the case locked and RWD only.

 

[concretejungle]

I think turbocruiser has a good write-up of him rebuilding that mechanism. Good pics and stuff to go by. Give er' a search and see what happens.

 

[jcolvin]

You can pull the four bolts off of the top of the actuator and remove the motor. The bolts are kinda hard to get to, but not bad. Three are easy to see. The fourth is about 2 o'clock and is up on a ledge so it's longer than the others.

Thanks.... I don't think this is possible without dropping the transfer case a little, correct?

You wouldn't happen to have any service troubleshooting steps to follow to make sure that it *is* the actuator that's fritzed before I pull the thing, would you? I don't have an FSM yet...

 

[speyrod]

JC,

Not much help on for you on the CDL other that I would remove the DS if your in a hurry.

? Do you happen to know Jillian Bice? from West Van but spends a lot of time on Galiano?

 

[FloridaFJ80]

Before you go on taking out your motor actuator I would check a few places first. This happened to me and it ended up being a bad switch. Here is my post.
https://forum.ih8mud.com/showthread.php?t=75588

 

[Gumby]

Thanks.... I don't think this is possible without dropping the transfer case a little, correct?

You wouldn't happen to have any service troubleshooting steps to follow to make sure that it *is* the actuator that's fritzed before I pull the thing, would you? I don't have an FSM yet...

Nah. There's room.







SYSTEM INSPECTION





PARTS INSPECTION



INSPECT CENTER DIFFERENTIAL LOCK CONTROL RERAY








(a) Check that there is continuity between terminals as shown in the chart.
HINT There is a diode between terminals 6 and 7. If the circuit shown no continuity, change the positive (+) and negative (-) probes and recheck the circuit.









(b) Apply battery voltage between terminals and check that there is continuity between terminals as shown in the chart. If continuity is not as specified, replace the relay.






pins and chart for step (a) and chart for step (b) for inspecting the relay

 

[Gumby]

INSPECT MOTOR ACTUATOR
(a)
Standard resistance: 0.3 - 100 ohms Using an ohmmeter, measure the resistance between terminals 2 and 3.
(b)
Standard resistance: More than 0.5 M ohms .
If resistance value is not as specified, replace the motor actuator. Using an ohmmeter, measure the resistance between terminals 2 or 3 and body ground.

 

[Gumby]

INSPECT CENTER DIFFERENTIAL LOCK SWITCH Check that there is continuity between terminals as shown in the chart.

 

[jcolvin]

hmmmm...

The "transmission relay" checks out ok except for the diode between pin 6 and 7. I get a resistance of 8.4 Mohms across it one way, and no continuity (infinite ohms) the other. So it does seem to be a diode, but should the resistance be that high? I don't know if this is what it should be...... I don't even know if this pin pair is critical for CDL actuation, and i guess the FSM doesn't say exactly what each pin is for.

I think my best bet is to try to get at the motor actuator harness and see if it is getting voltage. Its a PITA to get at though.

 

[Tools R Us]

Are you sure it's locked and not a bad switch or wiring? Can you hear the actuator motor run when shifted?

https://forum.ih8mud.com/showthread.php?t=59333&highlight=cdl

The motor harness is not that bad to get to, it's at the rear of the transfer. You maybe able to remove the actuator without removing anything else, but it's tight up there and I found it easer to work on with the front driveshaft removed and transfer lowered. The main reason being that the FSM is sketchy on gear timing details and I wanted to lock and unlock it a few times, confirmed by turning the drive flange before buttoning it up.

 

[concretejungle]

Sorry Tools, it was you not turbo who had the great thread with pics on the actuator. You deserve the credit.

 

[jcolvin]

Are you sure it's locked and not a bad switch or wiring? Can you hear the actuator motor run when shifted?

Yeah, its locked for sure. Steering is tight and wheels want to chirp round corners. No sound from the motor whatever position the switch is at.

I'm 80% sure my actuator motor is fritzed, but before I pull it off I'm going to make sure there's voltage at the harness. I assume I should get 12 v on at least one of the harness pins; if I get no voltage at all I'll try manaully applying voltage to the motor pins themselves.

You wouldn't happen to know what the two pins do eh? I'm assuming one is positive for engage and the other one for disengage (with negative grounded to chassis), or does the polatity reverse across the pins for engage / disengage?

 

[Tools R Us]

The polarity reverses across the pins for engage/disengage. If the motor is smoked, you can pull the motor cover and turn the armature to unlock, somewhat easier than removing the whole actuator.

 

[thelal]

If, when u try and put 12V to the actuator, and its NOT working (as in stuck or no noise) u can try and disengage manually.

I did this on my rear (locker) actuator for a month or two b4 I finally got around 2 fixing it. The 12V supplies power to a motor that turns a spindle. This spindle winds a spring mechanism that then in turn pushes in/out the locking pin into the diff housing.

If you take off the MOTOR actuator cover (it has 3 philip screws) and u're careful when u take it off (that the motor+little spindle doesn't pop out) - then you can wind that bugger by hand. Try clockwise (don't remember offhand which direction does what) and if it doesn't move then try the other direction. You should find that movement in one direction has an effect. You may not "feel" any big pop as this (un/)winding is only doing the larger cog spring instead.

Once u're windings are done and can go no further in that direction then put the cover back on and screws. You will likely still have 2 drive a little to disengage (and then hear the pop).

The front and rear lockers are easier to get to that the transfer case ones but 'should' be same mechanics.

I have pictures of inside of motor housing and actuator if that helps. Email me brendan dot lally atatatat mail dot com

 

[jcolvin]

Thanks for all the advice, turns out that the breather tube had gotten old and come off the nipple. It's impossible to see it up on top of the t-case, but it *is* possible to check by feel. The CDL actuator was full of rusty water, and the motor was burnt. A new actuator from cparts and now it engages smoothly and immediately. Replacing it wasn't as much of a PITA as I'd feared, but I wouldn't want to have to do it without a hoist and tranny case jack.

For a long time it had been sluggish engaging or disengaging, so in retrospect a sluggish CDL is a *hint* to pull the thing off and check/clean it before you need a new one.

 

[Tools R Us]

...

For a long time it had been sluggish engaging or disengaging, so in retrospect a sluggish CDL is a *hint* to pull the thing off and check/clean it before you need a new one.

Agreed, and check and/or upgrade the breather!