Is it normal to have water vapor inside the car taillight?
2 Answers
It is abnormal to have water vapor inside the car taillight. Avoid inferior bulbs: The performance of bulbs is crucial as it affects nighttime illumination and driving safety. High-quality headlight bulbs are a strong guarantee for safe driving. Perform regular maintenance: Cars require regular maintenance, such as checking whether the oil and oil filter need replacement and whether the brakes are functioning properly. Similarly, headlight bulbs should also be inspected periodically for integrity and replaced promptly when necessary. After driving approximately 50,000 kilometers or around 2 years, the brightness of headlight bulbs tends to diminish. At this point, it is advisable to have them inspected at a 4S store. If the brightness is insufficient, it is best to replace the bulbs immediately, preferably replacing both sides simultaneously to maintain uniform brightness.
My old car did the same thing last year—fogging up inside the headlights right after a wash. The mechanic said some condensation is normal with big temperature swings, as taillights have vent holes, and driving for half an hour with the lights on should dry it out. But if water droplets cling to the lens for days or there’s enough water to ‘raise fish,’ it’s likely a cracked lens or aged seals—especially in modified lights where the sealant wasn’t reapplied properly during reassembly. I ended up fixing mine with an aftermarket lamp assembly; OEM parts cost three times as much. Remember: water inside can short circuits, blow fuses, or even corrode the socket over time.
