Why is my brake light on?

Vlada June 06 2022

If you have a brake light on, it's important to understand why. It could be as simple as a burned-out bulb or indicate a more serious problem with your brakes. Either way, it's best to get it checked out so you can avoid any potential accidents.

What is the brake light?

The brake light is a warning light that comes on when the brake pedal is applied, telling the driver that the brakes are in use. In some vehicles, the brake light also doubles as the tail light. In others, the brake light is separate from the tail light.

Some vehicles have a third brake light, which is located in the center of the rear window. This brake light is usually only used when the brakes are applied hard, such as when making an emergency stop.

The reasons

There are a few reasons why your brake light might be on. One possibility is that the brake light switch is faulty. This switch is what tells the brake light to come on when you press the brake pedal, so if it's not working properly, the light will stay on.

Another possibility is that there is an issue with the brake fluid level. If the fluid is too low, it can cause the brake light to come on. This is because the brake fluid helps to apply the brakes when you press the pedal, so if there isn't enough, the brakes may not work properly.

Finally, there's also possible a problem with the actual brakes themselves. If the pads are worn out or there is a leak in the system, this can cause the brake light to come on.

If you're not sure what is causing your brake light to come on, it's best to take it to a mechanic so they can diagnose the problem. They will be able to tell you for sure what is causing the light to come on and can fix it so you can be on your way.

What to do if the brake light is on?

If the brake warning light comes on while you're driving, pull off in a safe location and switch your car off. The first and most straightforward thing to check is your emergency brake. Get out of the vehicle and double-check the amount of liquid in your brakes if the E-brake is completely released. If the brake level is too low, fill it to the brim with brake fluid and bleed your brakes until the light goes off.

Why my brake lights won’t turn off?

A faulty brake light switch is a typical reason for car brake lights that won't turn on. This component can be found beneath your dash near the brake pedal, and it's known as a brake light switch. It may be sticking closed or the portion has broken if your lights are disabled. The brake light switch may also be getting power, but the brake light bulbs may have blown.

Why are my tail lights on when my car is off?

If the tail lights are on when the automobile is off, there may be various reasons, depending on the car, including a faulty brake light switch or switch stopper, an incorrect trailer light plug, or a broken wiring harness. One of the brake light bulbs may also be burned out. 

If your brake light bulbs aren't working, try to replace them with aftermarket ones. 

How do I verify if the brake light is working?

There are only a few ways to test if the brake light is working. The first is to use a circuit tester on the brake light wires. The second is to ask someone to press the brake pedal while you watch the brake light, or you can do it yourself if you have a friend that can watch for you. Finally, many newer cars have a brake light test feature in the onboard diagnostics (OBD) system that can be used to test the brake light.


If your brake light is on, it's important to figure out why. There are a few potential causes, and some of them can be serious. If you're not sure what is causing the light to come on, it's best to take it to a mechanic so they can diagnose the problem. Once you know what is causing the brake light to come on, you can take the necessary steps to fix it and be on your way.