A headlight bulb is a halogen or HID (high-intensity discharge) bulb that is used to project a high or low beam. While most headlight bulbs are replaceable, there are some older headlights with a sealed beam design. Such sealed lamps can be filled with halogen gas to increase their light output. Regardless of the headlight design, a failing bulb can make the light inoperable and cause discoloration of its lens.
Headlight bulb troubleshooting
- Most headlight bulbs are easy to replace. However, it can be difficult to reach the bulbs on some vehicles.
- Both headlight bulbs should be replaced at the same time.
- Some headlights come with just one bulb for the low and high beams, while others can be equipped with separate bulbs.
- The headlights should be properly aimed. Make sure to check the adjustment after replacing the bulbs.
- If you have headlights with separate low-beam and high-beam bulbs, the first one should be located outward or above the high-beam counterpart.
- Depending on the headlights, they can come with halogen or HID (high-intensity discharge) or xenon bulbs. The latter ones are usually very expensive.
- Failures of the high-beam switch can affect headlight operation.