Troubleshooting Trailer Lighting that Stops Functioning When Headlights are On
Question:
I have a 2009 landrover discovery 4 and when towing caravan it is fine till lights turned on and the brakes stop vehicle from moving . The caravan has std flat 7 pin male plug into shop bought flat to round adaptor to the car. I have disconnected the blue serv. brake wire in the caravan plug and this has fixed the problem but I assume I now have no trailer brakes. Can you help with my next move.
asked by: Chris S
Expert Reply:
Your main problem is an insufficient ground for the trailer wiring. Try improving the connection of the main ground wire of the trailer wiring harness. Make sure it is attached to a clean metal surface. Or you can run all of the trailer wires back to the main ground. This is actually the ideal solution. But you can also check the current grounds for the lights to make sure they are making a solid connection to a clean metal surface. When the vehicle headlights and trailer running lights are on you are asking the wiring of the setup to draw it's most amperage.
What you described is the classic insufficient ground scenario so finding a way to improve the grounds will fix the problem.
Product Page this Question was Asked From
Hopkins 7-Way RV Style Connector with Molded Cable - Trailer End - 8' Long - RV Standard
- Trailer Wiring
- Trailer Connectors
- Trailer End Connector
- 6 - 10 Feet Long
- Plug and Lead
- 7 Round - Blade
- Hopkins
more information >
Featured Help Information
Instructions
Continue Researching
- Article: Trailer Wiring Diagrams
- Shop: Bonded 4 Wire - per foot
- Shop: Deka Jacketed 4-Wire - 14 Gauge - Per Foot
- Video: Pollak 7-Pole, RV-Style Trailer Wiring Harness Installation - 2000 Chevrolet Silverado
- Shop: Trailer Wiring
- Q&A: Does 7-Way Molded Trailer Wire Connector Have a Reverse Light Function
- Q&A: Where Does Yellow Wire of Trailer Wiring Connect to on 7-Way Wiring
- Q&A: What is the Difference between the Hopkins Trailer Wiring Harnesses HM20041 and H20046?
- Q&A: What Kind Of Wire Is Deka 16/4 Wiring DW03240-1
- Q&A: Wiring Up Trailer 7-Way that Uses Non-Standard Wiring Colors
- Q&A: How to Wire a Hopkins 7-Way Trailer Connector # H20046 1987 Layton RV Trailer
- Search Results: wire protector
- Search Results: trailer jack
- Search Results: ball mount hitch
- Search Results: wire protection
- Search Results: 16 gauge wire
- Search Results: hitch
- Video: Feature Breakdown: Pollak 10-Terminal Junction Box
- Video: All About the Trailer Wiring Junction Box
- Video: A Closer Look at the Deka Wire
- Video: The Low-Down on the Deka Wire
- Video: Complete Breakdown of the Trailer Wiring Junction Box
- Video: Comprehensive Review: Deka Wire
- Shop: Hopkins 7-Way RV Style Connector with Molded Cable - Trailer End - 8' Long - RV Standard
- Shop: Adapter 4 Pole to 7 Pole Vehicle End Trailer Connector
- Shop: Deka Wire - Jacketed 7-Wire - per Foot
- Shop: Wire Loom, 1/2" Diameter (per Foot)
- Shop: Hopkins 7-Way Blade Style Connector with Molded Cable - Trailer End - 8' Long - Auto Standard
- Search Results: wire
- Article: Brake Controller 7- and 4-Way Installation Kit (ETBC7)
on Trailer Wiring
