Troubleshooting Trailer Wiring Not Functioning Properly on 2014 Mitsubishi Outlander

Updated 04/25/2026 | Published 02/26/2015

Products Featured in This Question

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(156)

$64.97

Hook Probe Circuit Tester

(66)

$12.94

Question:

This kit did not work. one turn signal blinks and the other side is on solid. The connectors are correct for this car, but isnt this kit for a 3-wire light setup? The Outlander is 2-wire. according to my Outlander wiring diagram, pins 1 and 4 are used for the Rear Combination Lamp, both RH and LH. The Tow Ready harness uses what appears to be 1 and 4 on one connector, and 2 and 4 on the other connector. ideas? i would have included photos of the Tow Ready connectors, but this web page is broken when Upload Another Image is clicked

asked by: Gary

Expert Reply:

I checked with Tow Ready and they have confirmed that the Harness part # 118482 is a fit for your 2014 Mitsubishi Outlander. One thing you should do at this point is test the 4-way of the wiring harness with a circuit tester part # PTW2993 for voltage on all of the right pins when the taillight signals are being applied. Just like in the video I attached.

If the voltage checks out there but the trailer lights still don't function right then the problem is on the trailer wiring. That would mean that problem is either due to a ground issue or a short issue.

Make sure that the trailer side connector are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces. The light grounds should also be attached to clean and corrosion free bare metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding tongue, any of these things can interrupt the ground. Running jumper wires from the light grounds to the main trailer connector ground can help.

If the problem is on the vehicle side then I would first recommend you double check how the harness is installed on your vehicle, make sure all of the connections are good and tight. What you described can sometimes be due to the converter box shorting out.

What you will want to do is test the wires going into the box of the converter box for voltage with a circuit tester like the # 3808 to see if there is voltage going into the box when the taillight functions of your vehicle are applied, and then test the output side of the box to see if the current is making it through the converter. If not then the problem is that the converter box has shorted itself out and would need to be replaced.

Before you replace it you will want to inspect the wiring of your trailer to see if you can find anything that would cause the box to short out like corrosion or cut/exposed wiring. These boxes don't usually go out unless there is a short on the trailer that takes it out.

expert reply by: Jameson C

Clinton

5/7/2020

I have the exact same issue on my 2016 outlander GT. I am on my second kit now. I tested my trailer wiring with my dad's truck and everything worked. The wiring is all brand new and installed properly yet the left turn signal stays solid when it is turned on.

Chris R.

5/11/2020

I'm really sorry to hear about your experience with this kit. Everything I could find does say that the Outlander has a separate wiring system - so the converter on this harness (and the Curt alternative for this vehicle) is needed. I'm having a hard time coming up with what might be causing this, though. I'm sure you have verified that the connections themselves are secure and that none of the small pins on the plugs were bent, etc. Also check to make sure that the hot lead is securely connected to the battery and is properly grounded. Did your first harness ever work properly or did it have this problem as soon as it was installed as well?

Clinton N.

5/11/2020

@ChrisR it had the problem from the start. It was the curt brand and I assumed it was the black box that was not working. So I returned it and bought the tekonsha kit and it did the same thing. Would the ground wire placement have something to do with it? I have it on bare metal on the frame but maybe not low enough?

Chris R.

5/13/2020

@Clinton Thanks for the info. I don't think the ground location is an issue - a bare metal piece on the frame should be more than sufficient. I'm honestly not sure what's causing this. Did you test the 4-Way itself on the Outlander to see if it's getting constant power on the left turn/stop signal circuit when the turn signal is applied? If not, the issue could be on the trailer side.