How to Connect the Three Pins of an H4 Bulb?

[MadelineFitz]

The wiring method for the three pins of an H4 bulb is as follows: 1. The three pins are color-coded as black, white, and blue; 2. The black wire needs to be connected to the ground wire, the white wire to the low beam wire, and the blue wire to the high beam wire; 3. If the ground wire is not connected, the bulb will not light up, so it is essential to follow the correct sequence when installing the bulb. Additional Information: 1. There are two types of H4 bulbs: the first is 12V 65/55 watts, and the second is 24V 75/70 watts. Ordinary small vehicles use the first type. When replacing a faulty bulb, it is crucial to use the same model as the original to ensure the proper functioning of the vehicle's lighting system and avoid safety hazards. 2. A faulty vehicle bulb can compromise driving safety, especially at night. It is important to regularly check the bulbs for damage when driving at night. If any damage is found, replace the bulb promptly. The replacement process is quick and can usually be completed in just a few minutes.