Types of Car Lights & Car Lighting Resources
It goes without saying that your car’s lights are of utmost importance. Without good lighting, you can’t find items inside the cabin when it’s dark or see the road ahead at nighttime.
If you’re having problems with your car’s lights—or would just like to learn more about automotive lighting—we have plenty of information and resources available. After all, you don’t want to be left in the dark (pun intended) when it comes to your car’s lights.
Types of Exterior Car Lights
Vehicles have a wide variety of exterior lights, from headlights to tail lights—and everything in between. The lights help you see the road ahead and make your car visible to other drivers.
Here are the most common types of exterior lights found on passenger vehicles:

Headlights
You’re undoubtedly very familiar with your car’s headlights. When there’s a need to illuminate the road ahead, you turn the headlights on (or they might turn on automatically with the help of photoelectric sensors).There are four primary types of headlights:
Sealed beam
Typically found on older vehicles, sealed beam headlights are self-contained glass units with a filament and outer lens. The headlights are serviced as an assembly and do not have replaceable bulbs.
Halogen composite
By the 1990s, most production vehicles were equipped with composite headlights. The design includes a replaceable bulb—usually a halogen incandescent—inside a fixed lens cover. Inside the bulb, there’s a filament that glows when an electrical current is applied.
High-intensity discharge (HID)
Modern HID headlights put out more light and use less power than traditional halogen bulbs. HID bulbs contain two electrodes rather than a filament. Visible light is created when voltage arcs across the electrodes.
Light-emitting diode (LED)
Many late-model vehicles now have LED headlights. The technology uses multiple LEDs—semiconductor light sources that illuminate in response to current flow—to provide lighting. Although LEDs tend to cost more than other lights, they also last longer and use less power.
It’s also important to point out that headlights have both a low beam and high beam setting. The high beams cast light that’s brighter and projected further than that of the low beams. Depending on the system design, the high and low beams might be two separate lights or a single bulb with two filaments inside.
You’ll want to use the low beams during normal driving conditions. Meanwhile, the high beams are for use in low-visibility situations where you can’t see much of the road ahead. However, you shouldn’t turn on the high beams when there’s oncoming traffic, as you can momentarily blind other drivers.

Tail Lights
Your car’s tail lights turn on whenever the headlights are illuminated. The tail lights help other drivers see your car, especially when traveling at nighttime and in other low-visibility situations.
On many vehicles, the tail lights and brake lights share the same halogen bulb. One filament inside the bulb is for the tail light, and the other filament is for the brake light. Some vehicles also have a separate bulb for each circuit.
Fog lights
Most vehicles have round fog lights that are located below the headlight assemblies. You can also install fog lights as an accessory if your car didn’t come with them from the factory. The fog lights are used in conjunction with the headlights when driving through fog and similar low-visibility conditions. You can turn the fog lights on as needed via the headlight switch.
Although most fog lights have halogen bulbs, some newer vehicles have LED fog light assemblies.
Turn Signal Lights
There are turn signal lights at both the front and the rear of the car, integrated into the headlight and tail light assemblies. You can activate the turn signals via a switch to indicate your intent to make a turn or change lanes to other drivers. Most production vehicles have turn signals that use halogen bulbs.
Brake Lights
Anytime you press the brake pedal, a switch is activated, and the brake lights illuminate. Most production vehicles have brake lights that use halogen bulbs.
There is always a brake light integrated into each tail light assembly. In addition, all 1986 and newer models have a third brake light—referred to as a center high-mounted stop lamp or CHMSL—located near the rear window.

Hazard Lights
When you stop on the side of the road in an emergency, you should turn on the hazard lights to alert other drivers.
The hazard lights are part of the turn signal circuit—they use the same bulbs as the turn signals but have a separate switch. As such, when you activate the hazard warning switch, all four turn signals will flash.
Reverse Lights
Your car’s reverse lights (also known as backup lamps) signal to other drivers that you intend to back up. The reverse lights, which are mounted in the tail light assemblies, turn on automatically anytime the ignition is on, and the gear selector is in reverse. Most production vehicles have reverse lights that use halogen bulbs.
Daytime Running Lights
Many vehicles are equipped with daytime running lights (DRLs) that help make the car more visible to other drivers during the day. The lights turn on whenever the engine is running unless you turn them off or you turn on the headlights.
Depending on the system design, the DRL circuit can activate the headlights or separate daytime running lights. The DRL lights can use halogen, HID, or LED technology.
Side Marker Lights
Since 1969, all vehicles sold in the United States have had side marker lights. There are amber side marker lights at the front and red side marker lights at the rear. The lights help other drivers see your car when entering a roadway. Most side marker lights use a halogen bulb.
Puddle Light
Some cars (usually luxury models) have a puddle light that shines downward so that people entering the car can better see the ground. The puddle lights are typically built into the outside mirrors. When the driver unlocks the door with the key fob, the lights turn on automatically.

Types of Interior Car Lights
When you think of automotive lighting, the headlights and other exterior lights usually come to mind. But your car also has many interior lights, most of which use halogen bulbs, though some applications are starting to use LEDs.
Here are the most common types of interior lights found in passenger vehicles:
Dome Light
You’re probably familiar with the overhead dome light that illuminates your car’s cabin. The light can turn on automatically when the doors open (via door ajar switches), or you can turn it on manually, usually with a dedicated switch or the dimmer switch.
Reading Lights
You’ll find two small reading lights (also known as map lights) in the overhead console or headliner. There is one light on either side so that the driver and passenger can operate them individually.
Luggage Compartment Light
Some cars have a luggage compartment light that illuminates when you open the trunk or hatch. On some vehicles, the light comes on automatically when you access the rear cargo area. In other instances, you might have to turn the light on via a dedicated switch.
Dashboard and Instrument Panel Lights
Your car also has an array of dashboard and instrument panel lights, which can be broken down into three primary categories:
Warning lights
Alert you to a potential problem, such as a low coolant level or a brake system failure.
Indicator lights
Give you feedback regarding the state of certain features, such as the car’s turn signals and headlights.
Illumination lights
Provide indirect illumination to the instrument cluster, radio, etc.

New Car Lighting Technologies
All aspects of automotive technology—including the exterior and interior lighting—are constantly changing. Here are some of the new and upcoming lighting features you might encounter now or in the near future:
Auto-dimming Headlights
Auto-dimming headlights are a feature that’s becoming commonplace. When an oncoming car is approaching, the technology automatically switches between high and low beam headlights. As a result, there’s no need for the driver to toggle back and forth between the two settings.
Adaptive Headlights
Adaptive headlights move to follow the direction of the car’s front wheels, thereby improving visibility while cornering. Most systems also have a self-leveling mechanism that keeps the headlights properly aimed. The technology relies on computers and sensors for proper operation.
Smart Headlights
Smart headlights—which are also sometimes referred to as adaptive headlights, making things confusing—combine the functionality of traditional adaptive and auto-dimming headlights with other advanced functions. These headlights can change the brightness and direction of the light they emit, as well as the shape.
Laser Headlights
Laser headlights have a light source based on a blue laser diode (laser LED). The first production vehicle equipped with laser headlights was the European-spec 2014 BMW i8. While the technology has been used in various luxury models in Europe over the years, it has been slow to emerge in the United States.
Ambient Interior Lighting
One recent automotive trend is ambient interior lighting (also known as mood lighting). The feature uses LED lights in locations like the footwells and door trim to bathe the cabin in a soothing glow.
Some vehicles also allow the driver to set the ambient lighting color. Certain models even provide the option of having the lights pulsate along with the audio system.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.