How to Determine Trailer Light Wires to Install Them
Question:
On my new taillights, I have red,black,green. On camper I have white,red,green. Where does the black wire go on the lights? Can u send me a diagram?
asked by: Richard
Expert Reply:
We can help you determine how to figure out how to wire your trailer lights but there is not a diagram and I was unable to find your order number to determine the lights that you purchased from us. If you let me know the lights you bought I may be able to be a bit more specific, but if for example you purchased the Optronics LED Trailer Tail Light # STL78RB the red wire is the turn signal and brake light, the black wire is the tail light and the white wire is the ground wire. I imagine even if you don't have these exact lights they are also going to have the same wire functions.
All you need to do is use Cordless Circuit Tester # PTW2979 and have a helper engage the functions of your trailer when it is plugged in and match the wires on the lights to that of the trailer and you're ready to go. I have added a link to a help article on trailer wiring which I highly recommend checking out as well.

Products Referenced in This Question
Product Page this Question was Asked From
Optronics LED Trailer Tail Light - Stop, Turn, Tail - Submersible - 10 Diode - Oval - Red Lens
- Trailer Lights
- Tail Lights
- Stop/Turn/Tail
- Oval
- Surface Mount
- Submersible Lights
- LED Light
- 6-1/2L x 2W Inch
- Red
- Optronics
more information >
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