What is the Standard for Headlight Adjustment?
2 Answers
Standard for Headlight Adjustment: Park the vehicle to be inspected on a level ground. Move the inspection device to the front of the vehicle, ensuring the lens surface of the device is (30±5) cm away from the headlight's diffuser lens. Adjust the height of the device box to match the height of the headlight center from the ground. Below are the standard steps for headlight adjustment: 1. Inspection and adjustment of beam direction: Turn on the low beam of the headlight to be inspected. The beam passes through the lens of the device box and projects onto the screen inside the box. Visually observe through the viewing window and rotate the beam direction selection knob until the horizontal segment of the cutoff line (i.e., the light pattern) aligns with the solid line on the screen. 2. Inspection and adjustment of beam intensity: After verifying the low beam direction, press the low beam button to inspect the luminosity of the dark area. The device sets the maximum luminosity of the dark area at 625cd. Values below this are in the green zone (pass), while values exceeding it are in the red zone (fail).
As an ordinary person who often does DIY car repairs, I want to share what the standard for headlight adjustment is all about. Essentially, it ensures that the headlight beams don't blind oncoming drivers. Different countries have regulatory requirements—for example, in the EU, the ECE R48 standard specifies that the beam must not exceed the horizontal line at a distance of 10 meters and should be adjusted to a height of about 0.8 to 1 meter above the ground. When I adjust mine, I use a simple method: park on level ground, mark a line on a wall for measurement, then turn the adjustment screws to tilt the beam center downward by 1-2%. This isn't just to avoid fines—it's crucial for safe driving. Improper adjustment can easily cause accidents during nighttime driving, so I also recommend checking every six months, especially after changing bulbs or before long trips. After all, prolonged use can cause the lamp socket to age, leading to beam misalignment. Addressing it early can prevent trouble.
