What Would Cause a Headlight to Keep Burning Out?

Driving home late one night, you notice that one of your headlights is scorched out. You remember replacing that bulb not too long ago and wonder if there is an issue.  With winter’s dark days and nights around the corner, this is a concern.  Halogen bulbs and sealed beam headlights have very fine tungsten wire filaments inside that emit light when heated.  Constantly replacing headlight bulbs is not only an inconvenience and expense but also an indication that there could be an underlying issue with your vehicle.  

So what would cause a headlight to keep burning out?  Here are several problems that could be the cause:

• Vibration -- Vibration can be caused by driving over rough roads, the bulb is not securely mounted in the headlight assembly, there is a bent bulb socket or headlight housing, the headlight housing is not securely attached to your car, or the front wheels are out of balance.
• Touching the bulb -- You should always wear gloves or use a cloth if you have to touch the glass of the bulb.  If you touch the glass with your bare fingers, oil from your skin will adhere to the glass and may cause hot spots on the glass when the bulb is on, resulting in uneven heating and probably breakage of the glass. 
• Temperature extremes -- Heat is compulsory for the headlight filament to emit light; though the hotter the filament gets, the less durable it is. If you do an excessive amount of night driving or drive with daytime running lights, the increased amount of time that your lights are on will heat the filament to a higher temperature.  Also, if you drive in cold climates, bulb filaments become more brittle and are more susceptible to breakage, especially if accompanied by vibrations from rough roads and potholes.
• Turning on headlights before starting the car -- Normally, vehicles divert electrical power from any accessories that are on in order to deliver maximum power to the starter motor. If you turn your headlights on before starting your vehicle, the lights will turn off and then come back on when the engine starts, shortening the headlight bulb life.
• Water leaking -- Signs of condensation inside the headlight housing is a sign that water is leaking into the housing.  Because water and electricity don’t mix, any condensation may cause a short circuit. Also, condensation coming in contact with a hot bulb may cause it to break. 

Do you want to know more about what would cause a headlight to keep burning out?  Call our ASE Certified technicians at Proshop Automotive for more information about headlights and brake lights and to make an appointment. Our auto repair shop proudly serves residents in Colton, CA, and the surrounding areas.