What is a courtesy light bulb?
A courtesy light bulb is a small, typically low-wattage bulb used in vehicles to provide interior illumination. Also known as "interior" or "dome" lights, they are designed to light up the interior of the car when you open the doors or turn on the vehicle's interior lights.
Courtesy light bulbs are essential for providing visibility and convenience, especially during nighttime or in dimly lit areas. Car interior lights help you see inside the car, find seat belts, personal belongings, and access controls easily.
These bulbs are usually located on the door panels or the vehicle's ceiling, near the doors.
Courtesy light bulbs come in various types and sizes, depending on the make and model of the car. Most modern vehicles typically use LED bulbs for interior lights and door lights, whereas incandescent halogen bulbs or Xenon may be used in fog light illumination—and LED light bulbs are typically more expensive than halogen.
Different shapes of bulbs are available, too. The festoon bulb is commonly used in courtesy lights. It’s elongated and typically cylindrical in shape, with a metal or glass housing containing a filament or LED.
Unlike the larger and more general courtesy lights that illuminate the entire interior, map lights offer a more concentrated and adjustable light source to help the driver or passengers read or see specific objects (like maps) without affecting the overall cabin lighting. They’re usually located on the vehicle's ceiling, near the rearview mirror or overhead console, with individual light switches.
Plate lights for your license plate
, tail lights, and reverse lights to back up safely are not considered courtesy lights.Replacing non-functional or dim interior light bulbs is a simple and cost-effective way to ensure you have adequate interior lighting for safe and comfortable travel.
When should I replace the courtesy light bulb on my car?
You should consider replacing the courtesy light bulb on your car if you notice any of the following signs:
Dim or flickering light: If the courtesy light appears dim or flickers when you open the doors or turn on the interior lights, it may indicate that the bulb is nearing the end of its lifespan and needs replacement.
Non-functional light: If the courtesy light doesn't turn on at all when you open the doors or activate the interior lights, the filament may be broken.
Discolored or cloudy bulb: Over time, courtesy light bulbs may become discolored or cloudy, affecting their brightness and appearance. If you notice any discoloration or cloudiness, it's a good idea to replace the bulb for optimal illumination. You can also try the same cleaning process for the housing of headlight bulbs on the courtesy light bulb housing.
You can also replace the courtesy light bulb during routine vehicle maintenance or inspection to ensure all interior lights are in proper working condition. Not all vehicles can take LED interior lights, but it’s a good idea to install an LED light assembly if possible.
How often should a courtesy light bulb be replaced?
Courtesy light bulbs, like most interior car bulbs, have a long lifespan and can last for several years before needing replacement.
However, if you notice that the dome light bulb is dim, flickering, or not working at all, it's time for a replacement. In some cases, bulbs may also become discolored or cloudy over time, affecting their brightness and appearance.
As a preventive measure, it's a good idea to inspect your courtesy light bulbs regularly and replace them as needed to ensure proper illumination and convenience while entering or exiting your vehicle.
Can I replace my courtesy light bulb myself?
Yes, in most cases, you can replace your courtesy light bulb yourself.
Replacing a courtesy light bulb is typically a straightforward task that doesn't require advanced mechanical skills. The process usually involves removing the light cover, taking out the old bulb, inserting the new bulb, and putting the light cover back in place.
It's essential to consult your vehicle's owner's manual
for specific instructions on how to access and replace the courtesy light bulb properly. If you’re in California, consult the California Vehicle Code (CVC) requirements. These regulations cover the color, brightness, and positioning of lights, including those used for interior illumination.