Why Did My Brake Light Come On While Driving?

Brake light indicator on car dashboardThere you are gleefully driving down the road when suddenly, your joy is squashed by the feeling of impending doom because a funny light showed up on your dashboard. After all, it’s an exclamation point inside of a circle surrounded by parenthesis, who wouldn’t get excited? Your brake light can indicate something is amiss with your brake system. In this article we’ll explore the most common reasons the brake light has come on and what you can do to resolve it, so that you can resume that gleeful state of driving.

How does your car stop? There’s so much more beyond simply pressing the brake pedal. When your foot presses the brake pedal, your car transfers that force to the brakes via brake fluid. Because the brakes require significant force, your car must increase this force in order to make the vehicle stop. The brakes use friction and resistance to alter motive energy into heat energy. This is achieved by hydraulic force. Hydraulic fluid travels through the brake lines to create the pressure needed to press the brake pads against the rotors to slow or stop the car. Drum brakes operate similarly, however, instead of brake pads and rotors, brake shoes press against the drum.

Brakes are perhaps one of the most important safety features on your vehicle. Without them, going through a drive through would mean something else entirely. All joking aside, brakes are what allow your vehicle to slow down or stop. When they begin acting up, driver’s may feel uncomfortable or worried their vehicle may not stop at all.  When the brake light comes on, there’s no need to panic. There’s a reason this light has been triggered, here are the most common reasons why:

  • Your parking brake is engaged. Like any good car owner, you have the parking brake engaged when you’re parked (making life much easier on your transmission), but if you try to drive away, your car will let you know to disengage it by illuminating the brake light. The light may even be accompanied with a dinging sound to get your attention. Likewise, many vehicles are equipped with a sensor that lets the car know when the parking brake is on. If the parking brake is engaged, even slightly, your vehicle will believe it is still on and warn you before you get too far down the road. Driving around with the parking brake on is bad news. You could overheat the brakes, damaging the brake fluid or wear down the lining on the brake shoes or pads accelerating wear and eventually requiring new brakes.
  • Low brake fluid. This is the second most common reason drivers will see the brake light illuminate. A sensor within the brake master cylinder measures the amount of brake fluid present. When it gets low enough, the sensor will trigger the brake light to come on to let you know that the brake system needs to be inspected.
  • ABS troubles. Whether accompanied with the ABS light or not, the brake light can indicate trouble within the ABS system. Once you’ve confirmed the parking brake is off and there is plenty of brake fluid in the reservoir, a technician will need to inspect the vehicle and check for codes produced by the car’s internal computer.
  • Faulty sensors. The brake light could come on as a result of a faulty brake fluid sensor or parking brake sensor. A technician will need to confirm the issue and replace it as necessary.

If the brake light suddenly turns on while you’re driving, for safety’s sake, move safely off the road and pull over. Turn off your engine and check the brake fluid level. If necessary, add additional brake fluid to the reservoir. Restart your vehicle and watch the dashboard. Did the light go off? If yes, you may safely get back on the road and continue your journey. If not, or the brake fluid seems to be fine and the light is still on, it’s time to call in a professional. In such cases, it is recommended that you avoid driving the vehicle and instead call for a tow and have the vehicle taken to your trusted auto repair shop.

Brake troubles shouldn’t be taken lightly. Because brakes often need an up-close inspection to determine what the cause of your brake troubles are, it’s best to take your vehicle to an auto repair center for a professional opinion. A technician will be able to determine whether a faulty sensor is to blame, or if your brakes are in poor condition and need replacement.

While being able to get your car going is our business, we feel it is equally important you be able to get your car to stop. At Sun Auto Service we offer a free brake inspection to ensure all brake functions are working properly. Our technicians will measure the thickness of the pads and shoes as well as the rotors and drums and check hydraulic components for leaks. If the rotors and drums meet specifications as determined by the manufacturer, our technicians will be able to machine rotors and drums to remove blemishes and to verify the surface is ready for a new set of pads and shoes, which will save you money over complete replacement! Our technicians are truly the experts when it comes to brakes. Our ASE Certified Technicians specialize in brake services, ensuring your brakes are repaired correctly, the first time. Stop in today and see what makes Sun Auto Service the expert in brake service!