Headlight Bulb

On modern vehicles, the headlight bulb is replaceable, while a “sealed beam” design is used on older vehicles. The bulb or “sealed beam” can be filled with halogen gas, which provides better illumination than standard bulbs.

Symptoms of a Bad or Failing Headlight Bulb

• One or more of the headlights will not operate
  
• Discoloration of the headlight lens

Headlight Bulb Related Repair Advice

• The most common failure is simply a burned out bulb. However, the repair may be difficult since access to the bulbs can be limited on some vehicles.
• If one headlight bulb burns out, the other may not be far behind. In many cases, a repair shop will recommend replacing both blubs when one burns out
• Depending on the model, one bulb may contain both the high and low beam filaments; or, two separate bulbs may be used.
• Care must be taken when headlight bulbs are replaced so the headlight still aims in the right direction
• Systems using separate high and low beam bulbs will have the low beam located outboard or above the high beam
• Some vehicles use high-intensity discharge (HID) or Xenon type headlight bulbs, which can be very expensive to replace
• Failure of the headlight or high beam switch could also cause the headlights not to function correctly