Turn Signals on Boat Trailer Work, But Brake Lights Do Not
Question:
OK. I have turn signals,tail lts but no brake lights. Never had to use a converter before. What gives ???
asked by: Eric M
Expert Reply:
When you state that you never had to use a converter before, do you mean with this particular vehicle? That the brake lights worked with this trailer being towed by this vehicle before, but are not working now? Or do you have a new car, and you have hooked up the trailer connector and are finding that the lights on your boat trailer are not working correctly?
Most trailers use what we call a combined lighting system. This means that the brake lamp signal and turn indicator signal is combined on one circuit. So on the trailer, one circuit carries right turn and brake light signal, one carries the left turn and brake light signal, and one circuit carries the running lamps.
If your tow vehicle tail lights are wired the same way, you would install your 4-pole trailer connector directly into the tail light circuits, and everything works just fine.
However, if your tow vehicle uses what we call a separate lighting system, in which the turn signals and brake lights are on separate circuits, then a tail light converter will be needed in order to get the trailer lights to work correctly. If your tow vehicle has amber colored turn signal bulbs at the rear, you have a combined wiring system. A tail light converter combines separate turn signal and brake light signals into a single circuit, just like the trailer uses.
Many of the converters we offer are vehicle-specific, and are pretty much a plug-and-play installation. Some of the converters are more universal, and would splice into the tail light circuits of the tow vehicle. If you would care to respond with the year, make and model of your tow vehicle, I would be happy to make a specific recommendation for you.
If your trailer lights worked fine in the past with this tow vehicle, but now they are not, most likely one of the fuses that protect your towing circuits has blown.
Product Page this Question was Asked From
4-Way Flat Trailer Connector w/ 60" Harness and Wire Taps
- Trailer Wiring
- Trailer Connectors
- Vehicle End Connector
- 0 - 5 Feet Long
- Plug and Lead
- 4 Flat
- Tekonsha
more information >
Featured Help Information
Miscellaneous Media
Continue Researching
- Video: Review of Tekonsha Custom Fit Vehicle Wiring - Trailer Hitch Wiring - 118793
- Shop: Trailer Hitch
- Shop: Trailer Wiring
- Search Results: hitch
- Q&A: Trailer Running Lights Do Not Work but Brake Lights and Turn Signals Do Work
- Q&A: Trailer Hitch Wiring For 2018 Kia Rio
- Shop: etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"
- Shop: Draw-Tite Sportframe Trailer Hitch Receiver - Custom Fit - Class I - 1-1/4"
- Shop: T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Search Results: trailer hitch
- Shop: Curt Trailer Hitch Receiver - Custom Fit - Class II - 1-1/4"
- Shop: etrailer Trailer Hitch Receiver - Custom Fit - Matte Black Finish - Class III - 2"
- Q&A: Trailer Running Lights Keep Blowing Fuses when Turned On
- Q&A: Running Lights Work But Brake Lights and Turn Signals Do Not Work on Coleman Camper
- Q&A: Working Running Lights, But No Turn Signals or Brake Lights On Trailer
- Article: Trailer Wiring Diagrams
- Video: Trailer Wiring Harness Installation - 2010 Volkswagen Touareg
- Shop: Hopkins Active Tail Light Converter with Install Kit
- Shop: T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
- Search Results: 44649
- Video: Choosing the Right Trailer Wiring
- Q&A: What is the Difference Between a Class II and a Class III Hitch?
- Video: Choosing the Right Brake Controller
- Search Results: 68149
- Q&A: Wiring a Camper Shell Third Brake Light on a 2017 Chevrolet Silverado
- Shop: Brake Controller
- Search Results: 25580
- Video: Lippert Solera Slider Slide-Topper Review
- Shop: Fifth Wheel Hitch
on Trailer Wiring
Jeremy W.
5/14/2020
I have a wiring harness on my 2011 road glide ultra that is 5 pin. I have a four pin connector on my tow behind trailer. Could I simply splice my blue brake wire and add it to the yellow and brown turn signal wires and just change the end to a four pin? Thanks.