Replaced lock actuator twice, rear hatch handle still won't unlock

[InspectahDEck]

In my 05 yukon, i am unable to open the rear hatch due to it being permanently locked. I've replaced the rear hatch locking mechanism twice, two separate brands as I thought the first was faulty. I can manually climb back there and open it by pulling up on the metal hinge, but it remains locked from the outside despite my efforts. Here is a video of unlocking/ locking for context, but any help is appreciated.

 

[InspectahDEck]

Bump

 

[Fless]

Is the relay being powered and/or controlled? The ECC fuse powers the lock.

See the diagram at the link below, but navigate to your specific vehicle using the links at the top of your browser. You may need to dig further in the diagrams to see where the power/ground travels after the relay.

CHARM Liftgate Electrical

 

[tico]

I just had mine apart. It looks like you are missing the coupler part (circled in red) that allows latch to switch between locked and unlocked action. Here's a Pic and short video of how it should work. I had it out so had to manually switch it.

2002 Tahoe rear hatch latch