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

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1. Remove center climate control panel. Literally just pulls off with spring clips around its perimeter. Disconnect four connectors.

2. Remove rear plastic cover from climate control panel. Unplug CDL/Hazard switch module (small white connector).

3. Go back to truck, on the dangling connector C9 short together pins 4 (black) and 5 (red-with-blue-stripe) and turn ignition to “on”. You should hear CDL motor run retracting the lock. Shorting the wires is simply telling the CDL ECU that the button is “out”.

4. Drive around like a slow fool until the CDL releases.

5. Reassemble and replace the center climate control panel, leaving the CDL/Hazard module unplugged until you find a replacement module or fix that one.

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1. Remove center climate control panel. Literally just pulls off with spring clips around its perimeter. Disconnect four connectors.

2. Remove rear plastic cover from climate control panel. Unplug CDL/Hazard switch module (small white connector).

3. Go back to truck, on the dangling connector C9 short together pins 4 (black) and 5 (black-with-red-stripe) and turn ignition to “on”. You should hear CDL motor run retracting the lock. Shorting the wires is simply telling the CDL ECU that the button is “out”.

4. Drive around like a slow fool until the CDL releases.

5. Reassemble and replace the center climate control panel, leaving the CDL/Hazard module unplugged until you find a replacement module or fix that one.

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So, when you say “short together”, you mean with like a paper clip?
 
So, when you say “short together”, you mean with like a paper clip?
Yup. There will be 12V on the paper clip when you turn the ignition to “on” so keep it clear from any metal. And be gentle when inserting it into the connector pins, you don’t want to damage them internally. If the paper clip is too big find something smaller.
 
Yup. There will be 12V on the paper clip when you turn the ignition to “on” so keep it clear from any metal. And be gentle when inserting it into the connector pins, you don’t want to damage them internally. If the paper clip is too big find something smaller.
Super appreciate the detailed explanation. I will give all these suggestions a try and report back.

Not sure if I noted this earlier, but I noticed the CDL switch light was not illuminating last night and then the wife gave it a light whack and the light came on... so maybe it is the CDL button?
 
Super appreciate the detailed explanation. I will give all these suggestions a try and report back.

Not sure if I noted this earlier, but I noticed the CDL switch light was not illuminating last night and then the wife gave it a light whack and the light came on... so maybe it is the CDL button?
You mean the backlighting of the dash switch itself? That’s in-line with my thinking that the CDL/Hazard button module has flaky connections or is dirty. Examining it sounds necessary but my instructions above are focused on getting your CDL disengaged so you can drive normally. Fixing the flaky switch is the next step.

Also: I just remembered something you may want to do. Since the brake booster runs when the ignition is turned on it’s hard to hear the CDL actuator. You can connect the two wires together after the ignition is turned on and the booster has finished running so everything is quiet.
 
You mean the backlighting of the dash switch itself? That’s in-line with my thinking that the CDL/Hazard button module has flaky connections or is dirty. Examining it sounds necessary but my instructions above are focused on getting your CDL disengaged so you can drive normally. Fixing the flaky switch is the next step.

Also: I just remembered something you may want to do. Since the brake booster runs when the ignition is turned on it’s hard to hear the CDL actuator. You can connect the two wires together after the ignition is turned on and the booster has finished running so everything is quiet.
I actually have the button apart at home right now. It looked clean from what I could see. But correct, the back lighting on the CDL switch was out until we gave it a whack. I could also see that pressing the CDL button was making the hazard button illumination faintly flicker.
 
I actually have the button apart at home right now. It looked clean from what I could see. But correct, the back lighting on the CDL switch was out until we gave it a whack. I could also see that pressing the CDL button was making the hazard button illumination faintly flicker.
Well, the power for the button lights is separate from the power to the switch components so it may not be related. But suspicious nonetheless.
 
Gave it a shot and spliced the two wires together and nada. Also, wire #5 is red with a blue stripe?
Well, the power for the button lights is separate from the power to the switch components so it may not be related. But suspicious nonetheless.
 
Gave it a shot and spliced the two wires together and nada. Also, wire #5 is red with a blue stripe?
Correct, I made a mistake in my previous post (I’ll correct it). Pin 5 is indeed a red wire with blue stripe. Connect it to the black wire on pin 4 to simulate the CDL switch ‘off’.
 
Correct, I made a mistake in my previous post (I’ll correct it). Pin 5 is indeed a red wire with blue stripe. Connect it to the black wire on pin 4 to simulate the CDL switch ‘off’.
Yep, did that.. no go. No clicking, no motor noise, no nada. Neither did the replacement position sensor.
 
Ok, check that the 20A DIFF and 15A GAUGE fuses are good.
Checked and even replaced with spare fuses. They are good too.

I am just going to remove the actuator tomorrow morning. I seem to have enough access to all 4 bolts and only 8 more from the subframe if I need an extra inch or two space.

The previous owner who'd had it for almost all it's life said he never used the CDL and high gears. Maybe it's gunked up or just stuck...
 
Update, just got the diff actuator removed from the transfer case with the cross member unbolted. Only (4) bolts but even with them removed it needed a few light taps to break the seal, after that it pulls right off. As others have mentioned; be careful not to drop the gear which falls out of the housing. Mine rolled off my chest and down the driveway.

First impressions without disassembling it; the gears are locked solid and will not turn, I don't know if it's supposed to be like that or not. Will take it apart and report back.
 
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Checked and even replaced with spare fuses. They are good too.

I am just going to remove the actuator tomorrow morning. I seem to have enough access to all 4 bolts and only 8 more from the subframe if I need an extra inch or two space.

The previous owner who'd had it for almost all it's life said he never used the CDL and high gears. Maybe it's gunked up or just stuck...
Mall cruiser extraordinaire!
 
No luck repairing the actuator. Nothing looked particularly wrong. I re-assembled it and plugged it into the wiring harness. The relay under the dash started clicking once the CDL button was pressed but the motor would not spin unless I used my fingers to turn the gear and then it would turn on its own but not without some assistance.

Looks like i'll need to buy a new one... dealers quote them at $1200 but found some parts site for $430.

Anybody parting out a car in Oregon?
 
My CDL switch atop the t-case had failed in the 'off' position due to my 100s former life as a mall crawler. When I hit the CDL dash button, it engaged/disengaged CDL just fine. But, the t-case sensor did not show it as such so no dash lights and VSC stayed active.

It sounds like you have other issues, but FYI that switch seems to be a common failure and can be replaced for $20 on Amazon with a Beck Arnley 201-1788.
 
Does anyone know if the vehicle needs to be on in order to manually unlock the transfer case? I tried turning the gear on top of the transfer case with the actuator off and it's not budging. I tried it in neutral, and with the High/Low in Neutral.

Thanks...
 
HUGE progress just now... I cleaned the actuator unit earlier in the day, but was not getting it to function 100% of the time without any assistance to the gear.

I totally didn't see how the electrical motor side of the actuator was assembled when I took the casing off as everything fell apart once it came off. Well... the dangling rotor "brushes" were supposed to be installed onto the (2) springs that popped out of the base and once I figured that out I got the unit back together and tested it on the rig. It's WORKING 100% of the time.

I just have to button it back up tomorrow and hope it still works. I'm not sure what I did that made the actuator actually start to function but I spent some time cleaning the grease off the contacts.

(FWIW You can remove the actuator without dropping the TC)

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Part installed and working flawlessly. Thanks all for the help.
 

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