Signal-controlled intersection – advanced

In signal-controlled intersections, traffic lights control who gets to drive. Larger intersections often have multiple phases and filter arrows that require extra attention.

Meaning of the lights

Read the basics about traffic lights and signals if you need a refresher.

Filter arrows

• A green arrow gives free passage in the direction of the arrow, regardless of the other signal.
• The arrow can point right or left.
• When the filter arrow goes out, you no longer have permission to go in that direction.
• Green arrow with red main light means you can only drive in the direction of the arrow.

Signal phases and clearance principle

Large intersections can have multiple phases where different directions get green at different times. The principles are:

• Conflict signal: Opposing directions never get green at the same time.
• Clearance time: Between phases, there is a short period where all are red, so vehicles can clear the intersection.
• Pedestrian phase: Separate green phases for pedestrians and cyclists can occur between the vehicle phases.

Left turn at a signal-controlled intersection

Left turns are particularly demanding:

• Drive into the intersection on green and wait for a gap in oncoming traffic.
• If you have a left turn filter arrow, you can turn without waiting.
• If you are in the intersection when the light turns red, you must complete the turn to clear the intersection.
• Position yourself correctly in the left turn lane well in advance.

Special situations

• Police or manual direction always overrides traffic lights.
• In case of malfunctioning lights (extinguished signal), the normal right-of-way rules apply.
• Traffic lights at a crosswalk can have separate pedestrian signals that you must respect when turning.

Pay extra attention to pedestrians and cyclists who may have green at the same time as you.

Further reading

• Traffic lights and signals
• Crosswalks and pedestrians
• Right of way for pedestrians and cyclists
• Road Traffic Act – overview