It is getting dark on the Groningen ring road. Your car lights are on, but your trailer's lighting is on a separate switch and is still off. The trailer's reflectors are clean.
Have it wired so the trailer lights up together with the car
Switch it on whenever you yourself think it is needed
Drive on like this, the clean reflectors make you visible
Explanation
False — You rely on the reflectors instead of the lights. Reflectors come on top of the required lights; the trailer's rear lights, brake lights and indicators must work, at the same time as the car's. Book p.232.