Headlight Bulbs Explained: What To Do When They Burn Out
We’ve all seen it: A car is coming toward you on the road, but you may mistakenly think that its a motorcycle, especially at night. Or perhaps the other driver is purposely keeping his or her headlights on high, even when it isn’t appropriate – so you “flash” the oncoming vehicle. The other driver dims the headlights for you, and one of them goes dark. So whats up with this?
In both cases above, its obvious that the oncoming vehicle has a burned out or otherwise defective headlight bulb. Just like the bulb in your porch light, car headlight bulbs burn out and need to be changed once in awhile. Some vehicles will go for years without the need to replace a bulb, while others may seem to burn them out constantly. Headlight bulb life depends on a number of variables such as amount of usage, vibration, etc. If you regularly travel over rough terrain, then your headlight bulbs will fail more frequently due to vibration.
How To Replace A Headlight Bulb
On many vehicles built within the last 20 years or so, its a relatively easy job to replace these bulbs.
First, you’ll need to know which type of headlight bulb your vehicle uses. Your favorite auto parts store will have this information, and you can also usually look it up yourself at places such as Wal-Mart® if you know the year, make and model of your vehicle.
After you know what type of bulb you need, you can buy it at nearly any auto parts store, and some large department stores. You can also find good suppliers online.
In most cases, the headlight bulb will be a small halogen bulb which inserts into the headlight lens from the rear – i.e. under the car hood. There is usually also a plastic or metal lock-ring which holds the bulb in place. (see illustration). This lock ring is usually removed by turning it a small amount and then pulling it to the rear.
The bulb will have an electrical plug attached. The plug can usually be removed simply by pulling. DO NOT pull on the wires!. Grasp the plug itself near the point at which the wires connect and pull. In some cases there will be a locking tab which you can usually release with your finger or perhaps a small flat blade screwdriver.
The new bulb is installed by reversing the above steps; Insert the bulb into the lens assembly, install the lock ring, and then connect the electrical plug to the new bulb. Important: Do not touch the glass on the new bulb nor allow it to get dirty or oily in any way – doing so will greatly decrease its life. If the bulb does get dirty or oily, wipe clean with a soft cloth soaked with rubbing alcohol.
The steps above are typical, and may not apply to all vehicles. On some vehicles, replacing the headlight requires removal of part or all of the grille and the bulb is removed from the front. If you aren’t sure of the procedure for your vehicle, the best thing to do is to get a repair manual. The manual will contain information specific to your vehicle, and will be handy to have for future repairs.
