Which direction should the shading surface of H4 LED headlights face?
2 Answers
H4 LED headlights perform better when the LED chips are oriented left and right. Below is relevant information about LEDs: 1. Introduction: LED automotive lights refer to the use of LED technology for both interior and exterior lighting in vehicles. Exterior lighting involves thermal limits and EMC issues, along with numerous complex standards for load testing. LED automotive lights can be widely used to create the vehicle interior environment, with a lifespan of 50,000 hours. The robust structure of LEDs makes them less susceptible to vibration, and there is no significant decrease in light output brightness during use. 2. Suitable applications for LED automotive lights: LED automotive lights are suitable for various automotive electronic lighting applications, including headlights (high beam and low beam), fog lights, taillights, brake lights, turn signals, daytime running lights, pedal illumination, instrument panel lights, license plate lights, door lights, interior lighting, marker lights, navigation, entertainment systems, backlighting, and indicator lights.
I drive a lot and pay special attention to the orientation of the light shield when replacing H4 LED headlights. The correct orientation should be facing downward or toward the rear of the vehicle to effectively block upward light scattering in low-beam mode, preventing glare for oncoming drivers. Improper installation, such as having the shield facing upward or tilted, can cause light to scatter uncontrollably, which is not only illegal but also potentially hazardous. After installing them myself, I tested the beam pattern on my garage wall: checking if the low-beam cutoff line was clean and downward-facing. In actual driving, downward installation significantly improved nighttime visibility and safety. One related issue is that rough road conditions may cause misalignment, so I regularly check the tightness of the screws. Choosing a reputable brand is also crucial—some LED lights come with precise light-shielding designs that better match the vehicle's original reflector system.