How to access the Dahl weapon chest in the Outlands Canyon, behind the electric fence?

In Borderlands: The Pre-Sequel, in the Outlands Canyon (which you can access about 25% through the game), there is a Dahl weapon chest behind an electric fence. How can I access it?

Normally, there is a switch nearby that I have to throw at a fusebox to disable the fence. But I can't find one.

What I did find was a switch on the ground, on which I ground slam it to flip it from green to red. (To get a high enough height to ground slam this switch, I found a destroyable rock, which revealed an air geyser which I used.) Above the electric fence entrance, there are three orbs, all in red. Ground slamming that ground switch changes the first orb to green. But that's it.

I've been trying to find other ground switches but I can't.

Anyone know how to access this chest?

I made a video:

there's three touchplates. One by the air dome generator by the terra madre treasure quest, one by the garbage where you search for the map and fight the thresher, and that one thing there.

There are three touchplates that you have to slam within a time limit.

1. By the building between the Garage and O2 in the northeast of the electric fence.
2. By the O2 generator southeast of the first generator.
3. Below the slope with the electric fence.

Good luck!