Troubleshooting Left Turn/Brake Circuit on Trailer
Question:
Hello, Signal and brake light doesnt work on left trailer light, but running tail light does. What gives? I have 12v at plug, but no signals or brake lights. Thanks
asked by: Derrick O
Expert Reply:
If you have tested the left turn/brake pin on the trailer connector on the vehicle, and found that it works correctly, then the problem is in the left turn/brake lamp circuit on your trailer.
Start at the trailer connector itself, checking for excessive corrosion or damage. Clean, repair or replace as necessary. If you have a 4-pole trailer connector, the point where the wire enters the plug itself is a common failure point. Typically, the left turn/brake circuit is a yellow wire. Trace this circuit from the trailer connector back toward the lamp, looking for pinched or broken wires or loose connections. Repair as necessary.
I have linked you to our trailer wiring troubleshooting help article, which you might find helpful.
Product Page this Question was Asked From
Optronics Trailer Tail Light - Stop, Turn, Tail - Submersible - Incandescent - Oval - Red Lens
- Trailer Lights
- Tail Lights
- Stop/Turn/Tail
- Oval
- Recessed Mount
- Submersible Lights
- Incandescent Light
- 6-1/2L x 2-1/4W Inch
- Red
- Optronics
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