How To Wire In Trailer Tail Light With Additional Red Wire
Updated 02/03/2026 | Published 07/13/2024
Question:
I broke a taillight cover and was unable to find a replacement. So I got a complete unit, but dont know how to wire it. The old unit had one bulb and white, black and green wires. The new unit has 2 bulbs and an extra red wire to the top bulb. Should I pigtail the red to the black? I assume its a backup light, but unsure
asked by: Matt
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Expert Reply:
You are correct the 2nd bulb on your new tail light is for a backup bulb. As you do not have this function on your current lighting you should leave it disconnected if you are not going to run a separate wire on your trailer for the reverse function.
Product Page this Question was Asked From
Jeep-Style Trailer Combination Tail Light - Stop, Tail, Turn, Backup, License Plate - Red/Clear Lens
- Trailer Lights
- Tail Lights
- Brake/Tail/Turn/Backup
- License Plate
- Rectangle
- Surface Mount
- Non-Submersible Lights
- Incandescent Light
- 5-7/8L x 6-3/4W Inch
- Red
- White
- Optronics
more information >
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Robin H.
2/3/2026
Hey, how did things go with wiring your new tail light after leaving the red wire disconnected? Knowing how that setup worked could help others replacing the same style light.