Based on their light-emitting principles, headlight bulbs can be categorized into several types, including vacuum bulbs, halogen bulbs, and xenon bulbs. Vacuum bulbs and halogen bulbs are inexpensive and widely used, but their lifespan is relatively short, generally only a few hundred hours. Xenon bulbs can last 2500-3000 hours and offer better illumination, but they are more expensive. Regardless of the type of bulb, basic maintenance is similar. Just like changing engine oil and oil filters during regular maintenance, headlight bulbs also need periodic replacement. Generally, headlight bulb brightness will decrease every 50,000 kilometers or about 2 years. At this point, it's best to have them inspected at a 4S dealership. If insufficient brightness is confirmed, it's recommended to replace the bulbs, ideally both sides simultaneously, to avoid uneven brightness. I wasted time during my annual vehicle inspection because I didn't replace my bulbs in time after they became dim.
Another reason for reduced headlight brightness is environmental factors causing the headlight covers to age, which can reduce brightness by more than 50%. Dirty and aged covers can also blur the light, causing dizziness. Therefore, aged covers should also be replaced promptly.
