What Are the DOT Requirements for License Plate Lights

Question:

I rebuilt the whole back end of my travel-trailer and replaced the original taillights with Optronics STL178RB and therefore need a separate license plate light. ... I copied the following from your product description: “DOT approved when properly mounted. Requires single light mounted at trailer center, or 2 lights mounted on each side.” — I was wondering if this is indeed accurate and for some reason I must install both the license plate and light at the trailer center, or should it instead read “at license plate center”? — I’ve seen lots of trailers with license plates on the left side like my trailer originally was, and would like to install underneath the new STL178RB in the picture... So I wanted to be sure about this specific product because I’d rather not install it on the bumper which would otherwise be my only other option, because of the double-doors on the back. — Also, if you would please give a brief overview of what you mean by “DOT approved when properly mounted”... Thank you very much.

asked by: Michael M

Helpful Expert Reply:

You'll only need a license plate light like the # OPT77FR directly over the license plate, on whatever side of the trailer that you're mounting the plate. What the 2 on each side is referring to is that you could use 2 lights on each side of the license plate if you wanted, or 1 directly over the center of the plate, but I can understand why the wording here is confusing.

You can easily mount this under the # STL178RB you've already installed and make the trailer DOT compliant. I've linked one of our helpful articles that we did outlining the DOT requirements of trailer lights that you can refer to.

expert reply by: Erik B