Lighting and Optical Signals
A driver uses a brief flash of the headlights during the day. What is its usual purpose?
Reviewed on 26 Jul 2026
- A To indicate the vehicle has broken down
- ✓ To warn of one's presence or intention to overtake
- C To signal a left turn
- D To indicate that one is about to park
Why this is the correct answer
Flashing the headlights is an optical signal used to warn of one's presence or intention to overtake, replacing the acoustic signal where the latter is not permitted or is less effective.
More questions on Lighting and Optical Signals
- In the event of a breakdown, which of the vehicle's lights can you use to warn other drivers, in addition to the V-16 light?
- Summarising the lighting rules, the three key ideas to remember are:
- What are the three main functions of a vehicle's lighting system?
- When lighting is mandatory and the vehicle is moving, which lights must be switched on as a minimum?
- During which period of the day is the use of lighting mandatory?
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