If the brake light is constantly on the dashboard, the brake sensor might be faulty. But, if the vehicle is driving weirdly (pulling to one side), then the brake is actually applied, and this might be a caliper issue. Alternatively, it might be a power steering leak or a master cylinder issue.
Watch out: Stay alert if your car's dashboard begins to pop the brake system warning light. Your vehicle might be under progressive damage and can end up requiring hefty repairs in the future. Note that this notification pops up when you activate the parking brake; this doesn't mean there's an issue.
The most common causes for a brake warning light are:
Faulty master cylinder: The master cylinder mechanically pushes and pulls brake fluid creating hydraulic pressure to make the brakes react and stop the vehicle. This happens because the master cylinder has an internal piston that moves according to the driver’s movement with the brake pedal. If the master cylinder fails, the brakes are at risk, which causes the vehicle to display a brake warning light on the dashboard.
Faulty brake caliper: The brake caliper is an essential component in the braking system; it holds the pads and ‘clamps’ them around the brake discs, making force so the wheels stop rotating. Since the brake caliper is an essential brake system component, it’ll trigger a brake warning light if it fails.
Faulty brake booster: The brake booster uses vacuum pressure to make it feel light and easy to press on the brake pedal. If the brake booster fails, the pedal will feel stiffer, and the vehicle will display a brake warning light.
Low brake fluid: The brake fluid is essential so your vehicle’s brake components can create hydraulic pressure to ensure the car stops efficiently and with low effort. Low brake fluid means bad brake performance and risky situations, which triggers the brake warning light on the dashboard. The fluid typically loses volume due to a leak, commonly on brake lines.
Faulty brake pad sensor: Modern cars have sensors monitoring the brake pads. The pads are known to lose their thickness over time, which is a natural process of braking while driving. If these worn brake pads become too thin, they’ll lose efficiency, and sensors around them will shoot up a dashboard brake warning light.
A lit brake warning light can mean many things. First, check the underhood to see if the brake fluid reservoir is low; if so, you need to find out why. Additionally, if your car hasn't endured rain recently, check the back of its wheels and backing plates for any fluid. Also, keep an eye out for symptoms like a lower brake pedal or a brake pedal that sinks quickly under pressure.
These are typical processes and repair services that fix a check engine light issue
The most common reason for a car dashboard to show a brake warning light is due to thin brake pads. The brake pads are an essential brake component that endures huge stress and friction every time you press the brake pedal. They’re the ‘muscle’ behind your vehicle’s braking performance, clamping around the wheels and forcing them to stop. Therefore, if they’re too thin and worn out, the brake system loses efficiency and gets at risk of failing, prompting sensors to shoot up a warning light on the dashboard.
Symptoms it causes: Apart from the brake warning light on the dashboard you might also notice longer stopping distances, squealing noises, the vehicle pulling to one side, brake failure, etc.
High risk of priority: The brake pads are essential to the vehicle’s brake performance. Without proper pads, braking becomes unpredictable as the vehicle might simply take too long to stop, lose ABS performance, or fail to stop.
Brake pads are made of a material that degrades over time due to the friction created when braking the vehicle. The pads clamp around the wheels’ brake discs while the car is still running, so they keep clamping and degrading until there’s no more movement or the driver releases the brake pedal. However, brake pads are also designed to let you know when to replace them; typically they’ll make a squealing noise to indicate they’re too thin, or a brake warning light.
Go safe: Ask for a mechanic to inspect your vehicle’s brakes to investigate if the brake pads are worn out naturally and check if there’s further damage. Many shops do transparent vehicle inspections and lay out your options after investigating your vehicle’s conditions.
What’s a vehicle inspection? It’s “detective work” on your vehicle, checking its systems to see if anything prevents the car from working as expected. In this case, mechanics examine different parts of your vehicle to track if anything is causing the pads to wear out excessively. They’ll also check the condition of components during their inspection, noting which are causing the problem and which got affected by it, recommending to replace them in order of priority.
A brake system inspection is the most transparent process to understand why your vehicle’s brake pads are worn out. This is because many components in the brake system affect your brake pads, meaning something might be harming them, causing overwear.
Let’s read an example of how this kind of inspection helps to service a worn brake pad.
In a scheduled service, a customer stated their car was displaying a brake warning light on the dashboard. The customer also mentioned that their vehicle was making a squealing noise when braking and seemed to be pulling to one side.
The technician initially suspected something about the brake pads. The customer asked for a brake inspection since the brake pads weren’t due for replacement yet. While inspecting, the technician found that the front right pad was too thin and greasy. Next, the expert checked around the pads, noticing that the axle seal above the wheels leaked oil, and the oil was seeping and making the pads greasy.
This means the brake pads were excessively greasy, which was causing them to be sticky in the brake discs, leading to constant partial contact. Modern vehicles typically have a sensor that triggers the brake pad warning light.
Therefore the front right pads were wearing out faster than expected due to the leaking axle seal above it..
In this case, the mechanic put the “Immediate Action” tag on the brake pads and the leaking axle seal.
Below are just a few examples of typical Symptoms and Fixes your car might be experiencing