I have read too many stories about the door of the trunk being stolen to be sold online as an aftermarket part. It is actually pretty simple to take out, for this reason I always tried to lock it whenever I left my car parked anywhere.
The problem is that I am the type of guy that usually forgets to do stuff, so more than once I skipped locking the door after using it.
Also, it annoyed me big time everytime I had it locked, needed to open it for some reason, and surprise! my car is currently on so the keys are obviously being used therefore I have to turn off the car, bring the keys back, and open the door. I hated that so much.
For these reasons I decided to try this mod, it is actually pretty simple, it took me a few minutes of research and a few hours of installation, so now I want to share it with you guys. Stay tuned to learn how to install an automatic door lock on the back door of the trunk.
Overview
The idea is pretty simple, modify the lock on the back trunk door so that it locks and unlocks the door using the same signal as the passenger door locks on the rest of the car.
By doing this, you could just unlock the door by pressing twice the unlock button on the remote, and lock it by pressing once the lock button. Or you could lock or unlock it by using the lock buttons on the front doors.
Ideally we’d want to have that door unlocked only when passenger doors become unlocked. Not everytime the driver door gets unlocked.
Now with this in mind, let’s make a list of what we’ll need:
Now that we now what items we’re going to be using, let’s jump right into it!
1.- Remove plastic backing of the trunk door
Open the trunk and start removing all of the screws around plastic backing of the door.
Then to remove this panel, push it towards the car lifting the side closest to the trunk, as seen on video above.
2.- Remove pivot arm from current lock
This can be done by simply lifting gently a small red clip holding it in place on top of the lock and pulling it out. Then by softly pressing with a plier a white clip in the middle of the arm. Move it out the way.
3.- Align the power lock actuator with the factory lock and drill holes for its screws
The power lock actuator must be aligned with the factory lock so that the mecanism can work without putting too much stress in the plastic parts of the factory lock.
The actuator will go below the aluminum panel, held by screws. But now for convenience, place the actuator on top of the aluminum panel and mark where the screws must be placed in order to have the actuator aligned with the factory lock. Make sure to put the actuator the right way before marking/drilling!
After having these properly marked, proceed and drill small holes big enough to fit the screws that came with the actuator.
4.- Remove plastic panels inside cabin on passenger side, front door
Remove plastic panels on the front passenger underside in order to access the wires located underneath them.
The long shaped panel pops out just by lifting it gently. The panel on the footwell has a small screw on the back that can be removed by hand. Once you remove this, pull the panel backwards in order to take it out.
5.- Access door lock wires and splice audio wires in them
Disconnect the upper right hand connector, for additional reference it is the one located closest to the door, as seen on video above. Cut the cover in order to expose the wires and locate the red and green wire.
Splice audio wires to red and green wires using solderless wire connectors, you are free to choose which one you’ll splice into each wire, I chose to splice the tan colored wire to the red, and the other (silver) to the green.
6.- Test power lock actuator with newly spliced wires
Connect the silver audio wire to the green bullet connector from the actuator, and the tan wire to the blue bullet connector.
Test the actuator with your remote and check that it works properly, make sure that it opens and closes according to the button pressed on the remote.
Now that we know that it works as it should, let’s run these wires to the back!
7.- Run the wire through the firewall, all the way to the back of the car
Pass the audio wire under the plastic clips and reach the firewall under the front passenger seat carpet as seen on video above.
Remove the firewall, then pierce, or punch a hole on it so that you can pass the wire through, and run it all the way to the trunk of the truck. Try to avoid passing the wire close to moving parts. Try as much as you can to place it in fixed spots, for reference see video above.
Once you reach the trunk, follow the factory wiring tube that goes to the trunk camera, and pass the actuator wire using the same path as the factory tube. Try to use safety goggles or eye protection when working under the car, you don’t want dirt falling off into your eyes.
8.- Add female bullet terminals to audio wire and connect it to actuator
Cut any excessive audio wire you may have left and store it for future projects. Now add female bullet terminals to the audio wires in order to connect them to the male bullets that come preinstalled in the actuator. Then connect the wires the same as we did when testing, silver to green and tan to blue.
Next, place it under the aluminum panel where we previously drilled holes, and fix it in place with the provided screws.
9.- Carefully drill a small hole in factory lock to insert power lock arm
This step has to be done extra careful, we have to drill a small hole in the plastic part of the factory lock as seen on video, do it as centered as possible, use a very small or thin drill bit, make a hole big enough to fit tightly the aluminum arm that comes with the actuator.
There is only one chance at this step, but don’t worry, just make sure you do it centered with a thin bit and you’ll be fine!
10.- Insert aluminum bar into the actuator and mark where to bend it
Having drilled the small hole in the plastic arm of the factory lock, now insert the aluminum arm into the actuator and mark where you’ll have to bend it to pass it through the hole.
Make sure the position of the actuator is the same as the factory lock, in other words, verify that if the actuator is in “locked” position the factory lock should be the same as well.
Mark the aluminum arm in both locked and unlocked positions, you’ll notice that there will be a slight difference in where the mark will be, but that’s ok, we’ll use these two marks to find where to bend the arm.
11.- Bend the aluminum arm and insert it in the hole
BEWARE IF YOU HAVE A TONNEAU COVER!! DON’T CLOSE THE DOOR UNTIL YOU CHECK STEP 12
Bend the arm at the middle point between those two marks, I did it this way trying to minimize the error margin, so that plastic part from the factory lock wouldn’t be forced more than enough.
After it is bent at that point, bend it one more time so that it can stay secured in place after you pass it through the hole, this time you’ll have to guesstimate the where to bend it so that the aluminum bar stays close to be in parallel with the actuator, please see video above for reference.
After bending it one more time and checking it fits properly, cut any excess and install it. Check with your remote that it works accordingly and locks and unlocks the door.
12.- Place the pivot arm back in place
This step could’ve been done as step number 11, it would have been easier and quicker, but I totally forgot, so if that happens to you and don’t what to take out the aluminum arm (you’ll know what i mean when you try it), just completely remove the pivot arm by popping it out from the last red clip that is holding it, and move it over the aluminum arm.
Put it back in place like is was from factory, and test that your door opens and closes.
I learned this the bad way as I have a tonneau cover on my truck, I mistakenly closed the door without puting this pivot arm back in place, and locked myself out of my trunk. I had to force the tonneau cover enough to insert my arm and unlock the door by hand from the inside.
13.- Put everything back in place, leave everything as stock
Once you have your automatic power lock installed, proceed and put everything as it was in stock.
Put the back panel of the trunk and secure it in place with its screws, and put the front passenger plastic covers in place.
And congrats! you know have finished installing your power lock actuator!
