You must turn your vehicle headlights on:
- 30 minutes after sunset until 30 minutes before sunrise
- In fog
- When you can’t see at least 100m ahead of you.
In a car, motorbike or heavy vehicle, use dipped headlights when approaching other vehicles, following other vehicles, when a police officer is directing traffic and when parked.
Using a daytime running light, or dipped headlight during the day, will make you much more visible to other road users, whether you are driving a car or riding a motorbike.
If one of your headlights has failed then you must repair it immediately as it means your vehicle isn’t up to warrant of fitness standard. It also makes it more difficult for other drivers to judge your approach speed, distance and the size of your vehicle.
Headlights on right-hand drive cars are angled to the left so that they don’t dazzle other drivers. This also gives you a good view straight up the lane and to the side of the road. Some modern cars have headlights that swivel as the steering wheel is turned to help drivers when turning into driveways and around corners. These are called adaptive headlights.
Many cars will have daytime running lights for added security, but you still must turn your headlights on after dusk. If you have automatic headlights, leave them in the auto position and they will turn on when the light level drops. This does mean that they might turn on and off as you enter and exit a tunnel.
 Headlights are required 1/2 hour after sunset to 1/2 hour before sunrise, during fog, smoke, or rain and when visibility is less than 200 feet. In some states, headlights are required anytime the vehicle’s windshield wipers are on in continuous use.
