Your car’s headlights are important. Without them, driving in the dark would be an unnecessarily dangerous challenge. In some states, you’re required to drive with your headlights on if it’s raining, even in the middle of the day. So, when one of your headlight bulbs burn out, you’re best off replacing it right away. With one headlight, you’re not only driving with reduced visibility, which is a safety hazard, but your car will also fail your state inspection and you’ll run the risk of getting a ticket.

If you have an older car, you may have sealed beam lamps. It was fairly common on cars into the 1980s to have sealed beam headlamps. These, which were often rectangular or seven inch round units, were essentially large light bulbs. To replace them, you usually need to remove a piece of trim or the grill as well as whatever bolts or screws secure the headlamp to the headlight bucket. From there, you remove the electrical connector and then reverse the process to install the new unit.

Modern cars often have separate bulbs and lenses. If you have a lens that’s physically broken, you’ll need to replace that as well as the bulb if it’s burned out. Removal differs by make and manufacturer, but often, you’ll pop the hood of your car and be able to access the bulb from inside the engine compartment. Usually, you’ll have to pull off a protective rubber boot and a wire retaining clip before you can remove the electrical connector and bulb. With this style of headlight, it’s important not to touch the bulb glass with your bare hands if you can avoid it.

It’s usually best to replace headlight bulbs in pairs. Even if one is still working, chances are it’s in similar condition to the burned out bulb and doesn’t have much life left in it. But, it’s always a good idea to hang onto the good bulb as a spare. If you were just driving with the good headlight turned on, give it a few minutes to cool before removing it to avoid burning your hands.

Another reason to replace headlights in pairs is that the older of the two bulbs will often have aged and replacing only the burned out bulb will lead to uneven illumination. Also, pay attention to the replacement bulbs you’re purchasing. Just because a bulb is the same size and will fit in the headlight socket doesn’t mean it’s a correct match for the original bulb. Check your owner’s manual if you’re not sure what kind of bulbs you need.