CDL stuck engaged? Actuator doesn't function/make sound, but axle lockers work in high range (1 Viewer)

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I’m going to try and jump the CDL actuator using 12v from the battery, just want to make sure this is the correct plug (one on top that goes into actuator) to jump/ ground
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ppc

M Go Blue
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Is it strange that I'm getting 11.5v power to that switch/sensor in both high and low range, yet nothing occurs?
Not surprising at all. When the sensor is working properly it's ultimately establishing a ground connection. Not connecting is just a floating voltage. There is no electrical connection between the 4LOW Position sensor which activates the actuator and the sensor which which lights the dash lamp so switching between high and low range will make no difference.

From my observation you more than likely have at least two problems. First if would replace or refurbish the CDL sensor switch on the front of the transfer case. Second you may need to replace the 4LOW Position sensor (same part number) or get a working dash switch so you can test to hear is the CDL computer clicks and then hear the actuator function. In your current setup you can test the 4LOW circuit by pulling the plug, shorting the terminals and listen for the relays in the CDL computer to click.

After that is all properly working then attack the front and rear lockers. Finally make sure through better testing the the viscous coupler is not seized.

Bottom line is you need to progressively step through each of the subsystems in logical progression. What you have documented is just a random bunch of guessing and not properly testing. Example being the dash light second test getting the proper result.
 
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Not surprising at all. When the sensor is working properly it's ultimately establishing a ground connection. Not connecting is just a floating voltage. There is no electrical connection between the 4LOW Position sensor which activates the actuator and the sensor which which lights the dash lamp so switching between high and low range will make no difference.

From my observation you more than likely have at least two problems. First if would replace or refurbish the CDL sensor switch on the front of the transfer case. Second you may need to replace the 4LOW Position sensor (same part number) or get a working dash switch so you can test to hear is the CDL computer clicks and then hear the actuator function. In your current setup you can test the 4LOW circuit by pulling the plug, shorting the terminals and listen for the relays in the CDL computer to click.

After that is all properly working then attack the front and rear lockers. Finally make sure through better testing the the viscous coupler is not seized.

Bottom line is you need to progressively step through each of the subsystems in logical progression. What you have documented is just a random bunch of guessing and not properly testing. Example being the dash light second test getting the proper result.
Thanks for the feeback Phil, much appreciated.
This evening I removed the CDL sensor switch from the front of the case and tested it with a multimeter, both depressed and in its normal state, both giving back 0 continuity. I've read that this could be an issue because other people state that I should get back some sort of voltage reading, so maybe that is one problem. I'll buy two of those sensors and replace both CDL sensor and 4Low position sensor. I also ordered the CDL switch from Slee today, in hopes to do the 7 pin mod/CDL switch after this problem is resolved.
I have yet to hear the CDL relay click or make any noise, even after I shorted the CDL connector at the tcase with a paper clip, but the lights did turn on the dash.
The lockers function well, lights turn on in the dash, actuators engage, and the lockers function as I've tested while driving on my driveway. Isn't is strange that the lockers engage yet the CDL light does not engage? (Shouldn't the lockers only engage if the CDL light on the dash is ilumunated? I've heard the dash light is part of the system that enables the axle lockers to work. Maybe the issue is the sensor, yet the relay doesn't make noise)
And you're right, it has been a lot of guessing, mainly because this is a new platform to me, and it's hard to figure where to start, but I'm learning and reading as much as I can. It's been nonstop for the past 48 hours, and will continue to work nonstop till this is fixed.

Thanks again.
 

ppc

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I have yet to hear the CDL relay click or make any noise, even after I shorted the CDL connector at the tcase with a paper clip, but the lights did turn on the dash.
You need to be more specific in your descriptions. "CDL Connector" is ambiguous, there are three connectors for sensor switches and one connector to power/control the actuator itself. What I suggested was taking the connector off the 4LOW sensor and and shorting the terminals on the wiring harness. That should activate the relays in the CDL computer. If not, there is a wiring problem or a computer issue.


Isn't is strange that the lockers engage yet the CDL light does not engage? (Shouldn't the lockers only engage if the CDL light on the dash is ilumunated?
Yes, all that is correct, but ignore that for now. Concentrate on the CDL functionality first.


Because you know the front and rear lockers seem to be functioning properly most likely that computer, located in the passenger kick panel is working properly. To isolate it from CDL issues I would disconnect the plug to it until the rest of the system/CDL is working. That just eliminates one possible variable.
 
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You need to be more specific in your descriptions. "CDL Connector" is ambiguous, there are three connectors for sensor switches and one connector to power/control the actuator itself. What I suggested was taking the connector off the 4LOW sensor and and shorting the terminals on the wiring harness. That should activate the relays in the CDL computer. If not, there is a wiring problem or a computer issue.



Yes, all that is correct, but ignore that for now. Concentrate on the CDL functionality first.


Because you know the front and rear lockers seem to be functioning properly most likely that computer, located in the passenger kick panel is working properly. To isolate it from CDL issues I would disconnect the plug to it until the rest of the system/CDL is working. That just eliminates one possible variable.
I should probably invest in the FSM if I am to move any further. I am unclear on the locations/ functions of all the sensors on the tcase, besides the sensor/ plug at the front of the case on the top- that is the CDL actuator sensor/ controlled if I’m not mistaken.
I will take you suggestion of shorting the terminals for the 4Low sensor tomorrow morning and report back, is that the sensor on the very back of the tcase?
I’ll also disconnect the locker computer and ignore that for now until I have more data pertaining to the CDL issue. I’ll also read up on troubleshooting a seized viscous couple. Thanks for the reply.
 

ppc

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A electronic version (PDF) of the FSM and EWD - Electrical Wiring Diagram are available in the "Resorces" tab at the top of the page:


 
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A electronic version (PDF) of the FSM and EWD - Electrical Wiring Diagram are available in the "Resorces" tab at the top of the page:


Much appreciated. I should have found this sooner.
 
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Update:

1. Actuator works with 12v from the battery
2. CDL relay at drivers kick panel passes FSM inspection (12v test with continuity)
3. Took out all 3 sensors from the Tcase and depressed them all with a vice and tested 0 continuity with them depressed, which is an issue because they should be continuous while depressed. I will be buying 3 new sensors. Seems funny that ALL the sensors are bad.
4. 30a fuse is good, currently looking for the 10a gauge but CDL light turns on with paperclip trick so the 10a gauge should be good as well.

5. What am I missing? Would all three bad sensors be causing my problems? I guess we'll see.
 
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Update:
1. Swapped all 3 sensors from another fzj80 and was able to engage the CDL by shifting from Hi to Lo, also triggering the CDL light on the dash
2. CDL does NOT unlock when shifting from Lo to Hi, another problem to figure out
 
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2. Did you re-install the jumper plug in the connector for the CDL dash switch?
Are you asking if I reinstalled the CDL indicator switch wire harness/ connector into the CDL switch plug at the case side? Or are you asking if I reinstalled the old plug that was in the CDL dash switch (unused harness in '93-'97)?
I just talked to Christo on the phone, my CDL dash switch should be coming in the mail today. He also mentioned my symptoms sound like a mechanical failure inside the actuator or that my tcase is bound up, yet it's sitting on jack stands in my garage. Could an actuator fail and only lock the CDL and not be able to unlock it?
 
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Another piece of information:
The CDL acuator/ motor does not make a sound when shifted between Lo to N to Hi, as if it doesn't recognize leaving Low range. Actuator works/ relay clicks to ENGAGE CDL but does not work to disengage.
 

landcruising

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It seems you may have a bad CDL actuator. They can be stuck locked or unlocked from my research. I chased the same things you have one at a time, only to find a bad actuator. The vent hose on top was off and rotten letting moisture in when I did a deep water crossing. Ruined the inside. New they are very pricey, you can attempt a rebuild by cleaning up or regluing magnets etc or trying used. I found 2 used ones for about $200 no guarantee. I managed to find a new one in the United Arab Emirates for about $520 shipped, got it in 4 days. In the USA, I only found 3, all over $800 not including shipping. Good luck hopefully you get it working.
 
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It seems you may have a bad CDL actuator. They can be stuck locked or unlocked from my research. I chased the same things you have one at a time, only to find a bad actuator. The vent hose on top was off and rotten letting moisture in when I did a deep water crossing. Ruined the inside. New they are very pricey, you can attempt a rebuild by cleaning up or regluing magnets etc or trying used. I found 2 used ones for about $200 no guarantee. I managed to find a new one in the United Arab Emirates for about $520 shipped, got it in 4 days. In the USA, I only found 3, all over $800 not including shipping. Good luck hopefully you get it working.
Thanks for the reply, would be a shame if it was truly the actuator but I know of someone who has a few for sale for $200 used in Sacramento. I'll consider buying a new one if I can't fix mine.
 
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Are you asking if I reinstalled the CDL indicator switch wire harness/ connector into the CDL switch plug at the case side? Or are you asking if I reinstalled the old plug that was in the CDL dash switch (unused harness in '93-'97)?
I just talked to Christo on the phone, my CDL dash switch should be coming in the mail today. He also mentioned my symptoms sound like a mechanical failure inside the actuator or that my tcase is bound up, yet it's sitting on jack stands in my garage. Could an actuator fail and only lock the CDL and not be able to unlock it?
The jumper plugged into the unused harness. You would've had to remove it when you subbed in the hazard switch. Without a switch, that jumper needs to be in place or it won't toggle the CDL relay for it to unlock.
 

Squash

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Take a look or feel into the hole where the cdl sensor lives.
You should be able to feel with a pinky or see with camera if things are moving.
I do suspect your motor is stuck ,but at least try as this will make sense in the long run.
 
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The jumper plugged into the unused harness. You would've had to remove it when you subbed in the hazard switch. Without a switch, that jumper needs to be in place or it won't toggle the CDL relay for it to unlock.
Landcrshr! You are correct!
Is there an award for the biggest idiot of the week? Cause I’d definitely deserve it. Fixed all my problems with 3 new sensors and then finally I plugged that jumper plug back into the CDL button harness. CDL engages and disengages and all light work. Funny how all 3 sensors went bad.
I can’t believe I missed this but I learned a few things on the way.
Anyways, I took it out wheeling yesterday and it performed awesome, but the rear tubs/ AOE bumper need more trimming to fit the 37” mud grapplers.
The suspension worked well. I need bump stops/ limit straps because right now the shocks do all that work. Front 850j springs stayed in place and full flex, same with the rear 863j.
And I think I broke a birfield! So time for a knuckle rebuild/ axle fix.
I’m considering upgrading the shafts with RCV or just carry spares for the time being. Anyone have issues with the RCVs on 37s?
Thank you all for your helpful responses!
 
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Landcrshr! You are correct!
Is there an award for the biggest idiot of the week? Cause I’d definitely deserve it. Fixed all my problems with 3 new sensors and then finally I plugged that jumper plug back into the CDL button harness. CDL engages and disengages and all light work. Funny how all 3 sensors went bad.
I can’t believe I missed this but I learned a few things on the way.
Anyways, I took it out wheeling yesterday and it performed awesome, but the rear tubs/ AOE bumper need more trimming to fit the 37” mud grapplers.
The suspension worked well. I need bump stops/ limit straps because right now the shocks do all that work. Front 850j springs stayed in place and full flex, same with the rear 863j.
And I think I broke a birfield! So time for a knuckle rebuild/ axle fix.
I’m considering upgrading the shafts with RCV or just carry spares for the time being. Anyone have issues with the RCVs on 37s?
Thank you all for your helpful responses!
Glad you got it all sorted out!
 

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