Troubleshooting Running Lights on Trailer Not Working With Curt # C56217 on 2018 Toyota Highlander
Question:
Installed and turn and brake lights work but regular headlights on , tail lights don’t light
asked by: Chris T
Expert Reply:
First you will need to determine if the lighting issue is in the vehicle side of the wiring or the trailer. A Test Light # PTW2992 will help you to test the 4-way plug. Simply connect the clamp side of the test light to either the ground lug of the 4-way for to a good chassis ground. You can then activate the headlights on your 2018 Toyota Highlander to check for power to the brown wire connector. This is the one closest to the ground terminal on the 4-way.
If you have power here the problem is in the trailer wiring. You can continue to use the test light to follow the wiring to the lights looking for a break in the wiring or where it may have shorted to ground. I have linked an article below that will cover the trailer wiring.
If you do not have power at the 4-way you will want to inspect the connectors on the wiring harness to determine if there may be a damaged pin or a wire has come out of the connector. I have linked a video below for reference as well.
Lastly check to ensure that the fuse for the wiring is still good and that there are no damaged fuses in the vehicle circuit for the running lights.
Products Referenced in This Question
Product Page this Question was Asked From
Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Powered Converter
- Custom Fit
- 4 Flat
- CURT
more information >
Featured Help Information
Instructions
Miscellaneous Media
Continue Researching
- Shop: Trailer Wiring
- Shop: Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Shop: Trailer Hitch
- Q&A: Troubleshooting Trailer Lights Staying On All The Time with 2019 Toyota Highlander
- Q&A: Troubleshooting Low Voltage at Running Lights Pin with Curt Harness on Toyota Highlander
- Q&A: Trailer Wiring Harness for a 2015 Toyota Highlander without Factory Tow Package
- Q&A: Fuse Location for Installation of Curt Wiring Harness on 2018 Toyota Highlander
- Video: Curt T-Connector Vehicle Wiring Harness Installation - 2019 Toyota Highlander C56217
- Q&A: Troubleshooting Wiring Harness with 0.5 Volts Between Ground Pin and Other Pins
- Q&A: Troubleshooting Installation of Tow Ready Wiring Harness on 2016 Toyota Highlander
- Q&A: Troubleshootin the Curt T-Connector Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Shop: Curt Trailer Hitch Receiver - Custom Fit - Class III - 2"
- Shop: T-One Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector
- Shop: Tie-Down Anchor for Tow-Rax L-Track - Single Stud - 667 lbs
- Shop: Anchor Ring for Erickson O-Track Cargo Control System
- Search Results: 13290
- Search Results: e98840
- Video: Curt Trailer Hitch Receiver Installation - 2017 Mercedes-Benz GLC Class
- Search Results: 13383
- Video: Curt Trailer Hitch Installation - 2017 Chrysler Pacifica
- Search Results: kuat sherpa 2.0
- Shop: etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"
- Shop: CIPA Custom Towing Mirror - Slip On - Driver Side
- Shop: Towing Mirrors
- Article: How to Choose the Right Trailer Hitch Class
- Search Results: 44649
- Video: Choosing the Right Trailer Wiring
- Search Results: 68149
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Video: Choosing the Right Brake Controller