Trailer taillights are generally connected to
the towing vehicle's electrical system. The electrical wiring
for such a set-up may consists of using a Trailer Light
Converter, hosted on the towing vehicle, and a 4-way flat wiring
connection. In 2007 Uhaul Int'l, for example, used a 4-way flat
wiring connection for the lighting on its trailers.[1][2] The
taillights from the towing vehicle, or electrical system,
provide the trailer's taillights with appropriate signals and
electrical power needed for their operation.
