Troubleshooting Wiring Harness on 2015 Honda Pilot
Question:
I just put in a trailer wiring harness on my 2015 Honda Pilot and my light are not working on the trailer. I have checked the power source with a multi meter and Allison good but still no lights. I also have a 95 bronco and everything works fine so I’m stumped at this point. Any insight would be greatly appreciated.
asked by: Scott
Expert Reply:
Thank you for your purchase from etrailer of a wiring harness for your 2015 Honda Pilot, and there are a number of different issues that could be causing the problem with your lights not working, so there are a few different steps you can take to try and figure out the issue.
The first thing to do is take a look at your owner's manual to locate any trailer fuses or relays and ensure they are all there and in working order as this can often be the issue. For example, the Curt Wiring Harness # C56170 that fits your Pilot comes with a fuse that needs to go in the engine's fuse box.
If the fuses are good and in the proper place, test the connector on your vehicle after disconnecting it from your trailer with a circuit tester like # PTW2979. Check the wiring going into your harness from your tail lights to see if those wires are carrying the correct signals, if not, that confirms the issue is with the vehicle wiring. This is likely since you mentioned everything works with your other vehicle, so you'll need to inspect that wiring the best you can.
I have added links below to a pair of help articles on trailer wiring, including a troubleshooting guide for you which I highly recommend taking a look at. Additionally, to help prevent any type of corrosion in your connector, and increase its durability and lifespan I recommend using Dielectric Grease for Electrical Connectors # 11755.

Products Referenced in This Question
Dielectric Grease for Electrical Connectors, 2 oz.
- Accessories and Parts
- Trailer Wiring
- Wiring
- Dielectric Grease
- LubriMatic
more information >
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Vehicle End Connector
- Powered Converter
- Factory Tow Package
- 4 Flat
- Plug and Lead
- Plug-In
- Hidden
- CURT
more information >
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