Why it matters: Lighting and reflection of the trailer

Lighting and reflection are how other road users read your trailer in the dark. Red rear says 'end of the combination', white front and orange on the side draw its size. On a provincial road in wet snow, where visibility and road surface both work against you, an oncoming driver must immediately see where your trailer ends. If the trailer lights do not burn simultaneously with the car, the driver behind misses your brakes and indicators exactly when it counts. The conditional lights follow the trailer's size: the wider, heavier or longer it is, the more another driver must be able to see.