How to Open your Hatch if you can't open it using the Button
 

I was stuck with this issue running through my head for a couple days and I do not wish it upon any of you.

So either your button to open the rear hatch is broken or you are one of the many people who has had to repair/replace their hatch garnish and you closed the hatch with the button off.
Well, I decided it was time to repair mine yesterday and I ended up getting my hatch garnish and release button off, and putting my hatch interior panel back on (BIG MISTAKE) and closing it up for the night. The next day when I went to put the garnish and button back on, it hit me. I cannot open my hatch because the button is off and there is no keyhole and I put my interior panel back on, covering the connector on the inside. I called Toyota to see what they do in a situation like this. They said you have to fold down the back seats and crawl back there, remove the interior hatch panel and reconnect the button inside the car to open the hatch up. And that's great, unless you're like me and you have a large, custom fitted box in the back of your car that cannot be removed with the hatch closed.
So now I cannot open my hatch from the outside because my release switch is disconnected, I cannot connect it from the inside because I cannot access the connector with my system in place, and I cannot remove my system because the hatch is closed. I'm stuck in a loop. I contemplated breaking my subwoofer box apart inside my car and ripping it out to get to the panel. I contemplated completely removing my interior around my system to try to get it out. But instead, I got a wiring diagram and chased the wire to that switch figuring I had to be able to access it somewhere. It's much easier to do than I thought.

Here's how I found to Open the Hatch if you are completely screwed and cant open it from the back:

Remove your drivers side kick panel
You will see lots of wiring and connectors
There's a grey 12 pin connector on the bottom left
On the top left corner of that connector, there's an orange wire. This should be pin number 12.
Using any kind of probe or wire (I used some extra speaker wire I had) you need to ground pin 12 while the connector is still connected.
This completes the circuit the switch on the outside of the hatch normally completes.
As soon as you ground it, you will hear your hatch unlatch as if you pushed the button.

That's it, you're in!

Similarly, if you cannot open the hatch because the car has no power (dead battery), that trick will not work. In this case, flip down the seat, crawl into the trunk and pop off the plastic cover near the trunk latch. Once off, you can manually flip the latch from the inside.

I guess it depends on the reason to not be able to open the trunk.

Wow never even thought about this situation. even when i recently had a totally DEAD dead battery recently, i never had to get into the trunk at the time. I have always wondered why there was no key hole, not even a hidden one, for the trunk? aesthetic i guess? well thanks for the info!

I would like to make a dash button to open hatch and bypass the rear Hitch button, anyone got the plans to do that and how ? ty