What are Rear Lights and Their Purpose?

Rear lights, known as "bakljus" in Swedish, are a pair of red lamps positioned at the rear of your vehicle. Their primary purpose is to make your vehicle visible from behind, ensuring that other road users, particularly those approaching from the rear, can easily detect your presence, distance, and direction. This is fundamental for preventing rear-end collisions and enhancing overall road safety.

These lights typically illuminate automatically when you switch on your parking lights, dipped headlights (halvljus), or full beam headlights (helljus). In Sweden, as per traffic regulations, your vehicle's rear lights must be active during darkness, twilight, dawn, and at any other time when weather conditions or other circumstances reduce visibility to an extent where other road users might not otherwise notice your vehicle.

When and Why are Rear Lights Used in Sweden?

According to Swedish traffic regulations, rear lights are mandatory in specific conditions to ensure adequate visibility. You must have your rear lights on:

• During darkness, twilight, or dawn: These are the standard conditions where artificial light is necessary to make your vehicle visible.
• In conditions of poor visibility: This includes heavy rain, fog, snow, or any other weather circumstance that significantly reduces the line of sight for other drivers.
• When stopped or parked on a road: If you stop or park on a road in conditions requiring lights (darkness, poor visibility), your parking lights and rear lights must be illuminated to warn other traffic. A special rule applies to vehicles up to six meters long and two meters wide parked on roads with a speed limit of 50 km/h or less: it is sufficient to have only the parking and rear lights facing the road's centre illuminated, unless a trailer is attached.

The importance of rear lights is directly linked to preventing accidents. They provide vital information to drivers behind you, allowing them to react appropriately, maintain safe distances, and anticipate your movements. Failing to use them correctly can lead to dangerous situations and is a common reason for failing practical driving tests.

Rear Lights vs. Other Vehicle Lighting

It's important to differentiate rear lights from other types of vehicle lighting to ensure correct usage and avoid confusion, particularly for the Swedish driving theory exam:

• Brake Lights (Bromsljus): While also red and at the rear, brake lights are significantly brighter than rear lights. They activate only when the brake pedal is pressed, clearly signaling to following traffic that you are slowing down or stopping. Rear lights are always on when main lights are active, regardless of braking.
• Rear Fog Lights (Dimbakljus): This is a single, very bright red light, or sometimes two, at the rear of the vehicle, much more intense than standard rear lights. Rear fog lights are only to be used in extremely poor visibility (e.g., dense fog, heavy snowfall) when standard rear lights are insufficient. They must be switched off as soon as visibility improves, as they can dazzle drivers behind you.
• Parking Lights (Parkeringsljus): These often use the same bulbs as rear lights and are intended for similar visibility purposes when parked or stationary. They consume less power, making them suitable for longer periods. When parking on a road in darkness or poor visibility, both parking and rear lights usually need to be on, as described above.

Understanding these distinctions is key for correct lighting usage and for accurately answering questions on your Swedish driving theory test.

Rear Lights and Your Driving Theory Exam

Questions about vehicle lighting, including rear lights, are common in the Swedish driving theory exam. You should be prepared to identify:

• When rear lights must be used: Understanding the legal requirements regarding darkness, twilight, dawn, and reduced visibility.
• The purpose of rear lights: Their role in visibility and road safety.
• How rear lights differ from other lights: Especially brake lights and rear fog lights, in terms of brightness and function.
• Correct procedure for parking with lights on: Specific rules for urban areas and lower speed limits.

Familiarize yourself with the symbols on your dashboard that indicate activated lighting. Practicing identifying these situations will help you confidently answer related questions on your theory test.