Testing a Malfunctioning Wiring Harness on a 2021 Hyundai Tucson
Question:
2021 Tucson brake light not working after installation
asked by: Mike
Expert Reply:
This can be caused by a few things. First and foremost, you will need to check to make sure your ground is secure and attached to bare metal. It is best to not have this stacked with other wires and should be its own ground source. Once this is done, you will need to check your 4 Flat connection using a tester, like the Circuit Tester # PTW2993. The green wire is for the right turn signal, the yellow is for the left turn signal, and the brown wire is the brake signal, the one you are having an issue with. If one or more of these isn't working, you will need to replace the harness.
That covers the vehicle side. If all that checks out, it is most likely something on the trailer that is causing the issue. You will want to check all your ground connections to make sure they have a good clean connection to bare metal, making sure it is not aluminum. If they are LED lights, it is best to have each light grounded.
Once all the grounds are checked and or re-grounded, test the lights by plugging securely into the vehicle. If they still aren't working, you will also need to replace the harness. The Tekonsha # 118812 does have a 1-Year Warranty and this will be covered under that warranty. If this was purchased through etrailer.com, give our Customer Service a call at 1-800-298-8924 and we can get you all taken care of. If it was not purchased through us, you will need to contact the place the harness was purchased to get the warranty information.
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Products Referenced in This Question
Product Page this Question was Asked From
T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Custom Fit Vehicle Wiring
- Trailer Hitch Wiring
- Powered Converter
- Custom Fit
- 4 Flat
- Tekonsha
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