As time goes on, vehicle bulbs will be darker.

We call this phenomenon is luminous decay.

When vehicle bulbs happening luminous decay, you need to replace them quickly.

Meanwhile, you also need to take care of quality vehicle bulbs and to note color of temperature.

As you know, color of temperature of standard vehicle bulbs is from 3800k-6000k.

If you vehicle bulbs over 6000k, the lumens will be cut down so much.

The last is vehicle bulbs replacement after 5 or 10 minutes after car turning off.

Because vehicle bulbs are very hot, you need to cool them enough.