iMiEV Trailer Wiring Installation

by Ben N on September 12, 2016


Not long ago, I got the Torklift Central hitch installed on my car. As is, the car is ready for a hitch-mounted bike carrier or cargo tray, but to properly tow a trailer, I need a wire harness to connect to the trailer lights. So, I got out my wire strippers and set to work…

To start with, the Mitsubishi iMiEV is NOT a particularly common car, so there wasn’t any stock wiring that I could simply plug in. When I went to add a trailer connection to my S-10 truck, I simply bought a harness that plugged right in to the tail-light quick connect. No such luck being able to purchase something similar for this car. Instead, I mail ordered a Curt brand powered taillight converter. That device takes a signal from the tail-light, turn-signals, and brake light (3-wire system) and converts is down to the two-wire system a typical trailer uses.

IMG_1153I ordered a Curt 56146, ( which was a little more than twenty dollars on It also required a separate wiring kit, which is simply another piece of wire and a fuse. I already had those materials around, so I didn’t even bother to order the Curt 55151 kit that would match. (

In the rear-right corner of the car, there’s a removable panel, which gives access to the right tail-light connection. It’s also a great spot to place the Curt adapter and to roll up and store the trailer flat-four wiring. While I could access the tail-light connection from there, it was a tight fit, and I quickly realized that I should simply remove the plastic interior body panel.

With that out of the way, I had an easy view of the connection to the tail-light.

I also needed to know which wires performed the turn-signal, brake, and tail-light functions. One way would be to consult a repair manual wire diagram. However, I found a forum post at the MyiMiEV group where a user there had already identified which color wires were required.

I unplugged the tail-light connection and used a multi-meter to test the pins. That way, I could confirm that I had the wires correct. For example, I could put the positive connection of the multimeter onto the blue wire, connect the negative of the multi-meter to ground, and then activate the car’s right turn signal. On the multi-meter, I could see the voltage jump back and forth between 0V and 12V, indicating the car was flashing the right blinker.

IMG_1211With confidence that I had the colors right, I pinched the wires from the converter into the existing wires with the included “vampire clips”. Although this style connection is notorious for corrosion, all connections are on the INTERIOR of the car, where they will be out of the weather, and should hold up fine. The color codes of the car’s wires are as follows:
2012 Mitsubishi iMiEV (American Market)
Light Green = Right Tail Light
Violet = Brake Light
Blue = Right Turn Signal
(Dark) Green = Left Turn Signal

IMG_1201The Left Turn Signal is a Green Wire, but it’s located over on the left (Driver’s) side. I pulled back the interior body panel on that side, found the green wire, and tapped into it with a length of separate wire that I used as an extension to get the signal back over to the passenger side. There, I used a butt-splice connector to attach the wire to the Curt adapter.

With that, all of the cars wires were connected to the adapter. The adapter itself still needed 12V positive power and a ground connection. The ground was simple, I just pulled out one bolt that was already going into the sheet-metal body, slid it into the ring terminal on the ground connection, and then reinstalled the bolt. 12V positive power was more complicated.

IMG_1204The Curt powered converter requires 12V+ power of up to 10 amps. That means I needed to run a wire all the way to the front of the vehicle, through a fuse, and straight to the battery. I unrolled some 14 ga stranded wire, with a white jacket (which is also what I used to get the left turn signal to the right side.) I ran the wire from the back of the vehicle to the front, making sure I would have plenty of length. I removed the various lower interior plastic body panels, and ran this wire along side the existing wire harness in the car. I found that on the passenger side “B-Pillar” that I would have had to uninstall the seat belt to remove the panel. Instead, I simply removed the panels on either side, and fished the wire through.

I continued to bring the wire up under the passenger side of the dashboard. I have previously installed a “parking heater” on this car, and I needed to pass some wiring through the fire-wall. I did that at a penetration that’s on the floor right behind the center console, just below the HVAC controls. I reused this location by passing my wire though it.

IMG_1208Under the car, I pulled through the extra wire.
Next, from outside the front of the car, I ran a heavy piece of wire from near the battery, down through the maze of pipes and wires under the hood to my white wire, so that I could fish it back up. It’s much easier to try to pull a wire up and out than to try to push it!

Next, I crimped on a solderless wire connector butt-splice from the wire to a dedicated automotive fuse holder. On the other end of the fuse holder, I crimped on a ring terminal of an appropriate size to go to my battery.

With NO FUSE in the holder, I connected the ring terminal to the battery. Then, I headed back to the rear of the car, gently tugged out any slack, cut my 14 ga wire, and connected it to the Curt converter. Once all that was done, and I knew I wouldn’t accidentally have the wire grounded, I put the fuse back in the fuse holder at the front of the car.

Light_testerAt that point, all the electrical connections were made. I attached a trailer light tester to my new trailer wiring and tried it out by turning on the car, pressing the brake, using the turn signal, turning on the lights, and even remembering to test the hazard lights. The appropriate lights always came on the tester, so I knew I was ready to go.

After that, it was simply a matter of reinstalling all the plastic interior body panels.

All in all, the actual installation was very straight-forward. By far, the most complicated and time-consuming aspect was to run the 12V wire to the front of the vehicle for power. On a vehicle which has the battery in the rear (like a Prius or a Volt,) the installation would actually be VERY easy.

I also really like how the trailer wires can just be rolled up and set inside the small panel in the back corner. It’s a great way to keep everything out of the way when I’m NOT trailering!

I look forward to doing some towing with this car. I already tested pulling my Teardrop Camping Trailer, and was really pleased with how well it all worked (although that was with a jerry-rigged trailer light connection!) I think I’m going to get plenty of use out of my old utility trailer with this car. I’m working on rebuilding my garage, and need to transport quite a few items from my garage to a temporary storage facility while I work on the project.

Lots of short trips?! Sounds like a perfect job for an electric car! This time, with a trailer!

‘Til Next Time, Stay Charged Up!


Leave a Comment

You can use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

Previous post:

Next post: