How many times should the high and low beam lights be alternated?
3 Answers
No less than two times. Here are the relevant details: 1. Situations requiring high and low beam alternation: During the lighting test, when you hear prompts such as: approaching a sharp curve, approaching a slope, approaching a humpback bridge, approaching a crosswalk, or approaching an intersection without traffic signals, you should alternate between high and low beams no less than two times. 2. Special circumstances: When you hear the prompt to overtake and are instructed to use the correct lights, first turn on the left turn signal, then alternate between high and low beams no less than two times, and finally turn on the right turn signal.
As a veteran driver with over a decade of experience, I find flashing the headlights twice to be the most reliable approach. When overtaking or alerting the vehicle ahead, I'm accustomed to quickly switching between high and low beams twice as a signal—too few flashes may go unnoticed, while excessive flashing can be unsafe. For instance, on highways, I've tried flashing just once with no response, necessitating a second attempt; more than three flashes becomes too frequent and distracting. In low-visibility conditions like night or fog, I'll flash twice or more to ensure visibility. The key is to gently toggle the lever without abrupt movements—the goal is polite communication, not startling others, while maintaining a safe distance. Based on this experience, two flashes strike the optimal balance between effectiveness and courtesy.
I often study car knowledge, and this question is about alternating the headlights once or twice when overtaking. During operation, quickly toggle the light lever back and forth to flash the high beam once each time. Two flashes are most effective because they are noticeable but not prolonged, reducing interference with the vision of the car ahead. If the road conditions are complex or the lighting is dim, you can add one more flash, but no more than three to avoid excessive bulb wear. From practice, I've found this number to be the most efficient in prompting others to react promptly. Don’t forget to pair it with a light tap of the horn for a more comprehensive approach, but use it moderately and don’t over-rely on the lights. After all, safety comes first—consider the feelings of other vehicles to ensure smooth driving.
