Troubleshooting Dimming Trailer Lights When Braking And Using The Turn Signal
Question:
I have a 2001 Suburban. All of the car lights work. When hooked to a trailer, the trailer turn signals work, but when the brake is on with the right turn signal, the left brake light goes out. If the headlights are on, with the right turn signal, the left brake light dims. This happens on two different trailers.
asked by: Doug G
Expert Reply:
Hi Doug,
Based on the symptoms you're describing it just sounds like you're dealing with a lack of power. Everything works until you start putting too much of a load on the harness. Does your Suburban have a factory tow package/7-way or did you have to install one aftermarket? Older vehicles used to pull power from the vehicle tail lights to power the trailer lights and ended up drawing too much power and causing the lights to dim. In this kind of situation you can either replace the wiring with a harness that runs up to the battery for power or you can replace the lights on the trailer with LED's to lower to demand to something the harness can handle.
Swapping out the lights will likely be both the easier and cheaper route to take and will end up being more energy efficient. Let me know what you think and we can move forward with whichever route you'd prefer.
Doug G.
4/16/2024
Thanks for the reply Kevin! Yes, the Suburban has a factory tow package with a 7 way plug. The plug itself and the trailer brake are after market. The trailer lights are already LEDs. Can you tell me more about the harness you spoke of? Thank you, Doug
Product Page this Question was Asked From
Standard Trailer Light Kit with 25' Wire Harness
- Trailer Lights
- Tail Lights
- License Plate
- Rear Reflector
- Side Marker
- Side Reflector
- Stop/Turn/Tail
- Square
- Kit
- Surface Mount
- Non-Submersible Lights
- Incandescent Light
- 5L x 4-1/2W Inch
- Red and Amber
- Optronics
more information >
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Doug
4/18/2024
Thank you Kevin. I'll follow your advice and check the voltage at the 7 pin plug. Take care, Doug