2021 2500 Tailgate Issues

[MangoAV8]

Hello everybody, long time lurker first time poster. 2021 2500 Tradesman.

I’m at wits end with my tailgate and am looking for any other ideas before taking it to the dealer. The tailgate had the recall completed and was working fine for ~1 year or so before somewhat overnight, nothing would work to get it open. With an aviation maintenance background I started with the fuses (checked F14 and F30 based off other threads, both checked good), traced the wire bundle back, and after not seeing any obvious issues, got to the tailgate. I removed the tailgate, disassembled the wiring harness from the tailgate and checked the harness as well as all connections for scoring/corrosion or any cuts in the harness. All fit snugly and seemed to be fine. Interestingly enough the rear view camera, which shares the wiring bundle until splitting, works perfectly…which leads me to three possible culprits:

1. There’s another fuse I’m not aware of…

2. Both tailgate latch mechanisms failed simultaneously. Unlikely but an option.

3. The pressure switch in the handle (my vehicle doesn’t have the key fob opener) failed.

My gut tells me it’s number 3, but before I start down this eternal rabbit hole, was curious if there are any other avenues I could check.

Appreciate any help or recommendations!

 

[CdnHO]

I am betting one or more of the wires between the bed and the tailgate may be broken where they bend back and forth. May not be visible if the insulation is still intact. You can try wiggling the wires while activating the handle switch, hoping they make contact. I have seen several complaints about these wires breaking. I should have the schematic kicking around somewhere if you need it.

 

[MangoAV8]

Gonna be hard to get at, but one or more of the wires between the bed and the tailgate may be broken where they bend back and forth. If you can remove the panel, you should be able to trip each of the latches manually. You can try wiggling the wires while activating the handle switch, hoping they make contact. Watch your fingers in case the tailgate drops. I have seen several complaints about these wires breaking.

I’ve been able to access the latches and pop them open, and the entire tailgate has been removed from the truck. Figured better off than stuck on.

 

[CdnHO]

Hope this is of value.

 

[MangoAV8]

Hope this is of value.

Thanks!

 

[CdnHO]

Here is another one.

 

[CdnHO]

Hope airplanes are easier to diagnose. LOL

 

[MangoAV8]

Hope airplanes are easier to diagnose. LOL

I wrote so many gripes after flights for the actual maintainers that after a decade or so I became an honorary troubleshooter…just enough to have an idea what might be the problem but not enough to trust I wouldn’t mess it up.

 

[CdnHO]

I ran into an issue a couple of times where the right latch would not release due to the sun heating the tailgate on a hot day. Heat must have warped the tailgate. Pushing the tailgate toward the bed released the latch, so made a small adjustment to the latch pin. However I could hear the latches clicking, which I assume is not the case with your truck. Of course there is a module involved (BCM) which muddies the waters. Might be worth checking for codes.

 

[MangoAV8]

I ran into an issue a couple of times where the right latch would not release due to the sun heating the tailgate on a hot day. Heat must have warped the tailgate. Pushing the tailgate toward the bed released the latch, so made a small adjustment to the latch pin. However I could hear the latches clicking, which I assume is not the case with your truck. Of course there is a module involved (BCM) which muddies the waters. Might be worth checking for codes.

That’s exactly my gameplan. Going to grab some more tubing, strip all of the tubing off (multimeter check wasn’t conclusive, so my current suspicion is bent wiring as you recommended) and run the codes.

 

[PRS]

The tailgate release button supplies a ground to the BCM, which then supplies power to the unlatch solenoids, which have their own ground, but it is common to both latches.
You could monitor pin 4 at the latch with a test light and activate the button to see if the BCM is sending voltage. If there is no voltage there are 5 connections between the BCM and the unlatch solenoids. The tailgate handle release button circuit uses those same connectors.
You could also ground pin 1 at the tailgate handle button and check for voltage again, to verify the button.
In mine there is a tailgate release button in the overhead. If that one doesn’t work either, then you have to suspect the BCM, or the power circuit or the common ground for the latches.