Brake Warning Light Diagnosis And Repair: When & How

The brake system warning light illuminated on your dashboard is a warning sign that there’s something wrong with your braking system, and you should get it inspected as soon as possible. This could be anything from low brake fluid levels, worn brake pads, or shoes to a more serious problem such as a damaged internal component.

Brake repairs can be complicated and dangerous, so it’s best to have the issue checked out by an experienced technician who can identify the exact issue and suggest how to proceed.

No matter what the cause of your brake warning light is, it’s important not to ignore it and always ensure the brakes are inspected in time. If left unchecked for too long, the severity of the repair could get bigger—resulting in additional expenses and increased risk of failure while driving.

Remember that timely servicing is far cheaper than a major overhaul if you wait too long. Read on and learn more about it.

Types of Warning Lights

1. Brake Light

The bright illuminated “Brake” or encircled exclamation mark on your dashboard is a warning that should not be ignored. If this indicator light comes on, it could indicate a low brake fluid level in your car’s hydraulic system.

This could be caused by delaying refilling the brake fluid reservoir after its initial fill-up (typically done every 30,000 miles). Additionally, a brake fluid leak might decrease pressure and reduce the brakes’ effectiveness when you press on them.

2. ABS Light

The anti-lock brake system (ABS) is an important and potentially life-saving feature in rainy, slick, or snowy conditions. The ABS helps prevent the wheels from locking up under heavy braking by measuring tire rotation and compensating when it detects the wheels slipping.

With this loss of traction that could be caused by too hard of a brake application, your engine computer monitors the ABS and triggers an ABS light warning if there is faulty wiring, damaged wheel speed sensor(s), or an iffy ABS pump.

3. Parking Brake Light

The parking brake light is an important indicator on your dashboard, as it ensures that you have properly released the parking brake before you take off. It’s typically located on your car’s rear brakes and appears as a yellow or red encircled “P” when the parking brake isn’t adequately disengaged.

This warning could mean the parking brake system is worn or the sensors malfunction. Even if you apply the parking brake with just one click, this can cause unnecessary wear and tear on your brakes and even pose a risk to your safety.

4. Brake Pad Wear Indicator Light

As your brake pads experience wear and tear, the indicator illuminates to alert you to take appropriate action. Illustrated by a circle inside dotted brackets, this warning signifies less than a quarter inch of thickness left on the brake pads. Your braking performance could become diminished over time, so replacing worn-out pads is important before it becomes a more serious issue.

When Did the Brake Warning Light Show Up?

The brake warning light is an important feature in modern cars, designed to alert the driver to possible problems that could affect the car’s ability to stop. The first autos with this feature appeared around the mid-1990s, but it has become increasingly robust and precise.

This gives drivers an early signal that something might be wrong with their car’s braking system and provides them ample time to check it out or have a mechanic do so before continuing their route.

When the brake warning light comes on, there can be several causes, ranging from low brake fluid levels to more serious issues like worn-out brake pads or discs needing replacement. It is critical that once this signal appears, the driver immediately stops and carefully inspects what could be causing the issue instead of simply continuing on their way, as this could lead to dangerous consequences due to malfunctioning brakes.

Moreover, most newer cars have multiple hydraulic braking systems, which can prevent full braking failure if one system malfunctions or fails; however, these systems will eventually fail if not tended to immediately after a warning light appears.

How to Identify Those Issues?

Regarding brake warning lights, the first step in identifying the cause of the issue is to check the fluid level in your brake system. Low brake fluid can indicate a serious problem and may require an inspection by a qualified technician.

If the fluid level is low, check for any leaks or other visible signs of damage and repair or replace any damaged parts before topping off with new fluid.

Another indicator of a potential brake issue is worn-out brake pads. Worn-out or damaged brake pads can cause the warning light to appear and should be inspected immediately. You’ll need a flashlight and a flathead screwdriver to inspect your brake pads.

First, check for any visible signs of wear or damage on the outside of the pad. Next, use your screwdriver to press the pad while looking through its wear indicator window to check for any cracks or worn-out spots. If you notice any of these issues, it’s time to replace your pads.

How to Fix This Issue?

1. Check Brake Fluid

Firstly, you must examine the brake fluid reservoir under your bonnet or hood. The level of the fluid should be clearly marked on the side. If it’s below the minimum threshold, then topping up with more of the same fluid type may resolve any issues – if not, then it’s time to speak to a mechanic as there may be a leakage problem.

Your mechanic can then use a special gauge to measure the pressure and check for any problems, ensuring your brakes work properly when required. Checking your brake fluid is just one way to ensure that your car stays in top condition – don’t forget about other important aspects like tyre pressure, oil levels, and suspension checks.

2. Anti-Lock Braking System Check

The Anti-Lock Braking System (ABS) is an important safety component of modern-day vehicles that helps to reduce the chance of tire skidding during sudden braking. Diagnostics and codes must be checked regularly to ensure proper functioning.

When the onboard computer senses any problems with the vehicle’s ABS, it records diagnostic trouble codes (DTCs) accessible by a scan tool or code reader. By retrieving these codes, service professionals can quickly identify what issues may be causing the ABS dashboard light to flash.

3. Go to An Expert

When it comes to brake repair, sourcing the right parts and doing the work can be daunting. If you are not careful, you could end up causing irreparable damage to your vehicle. For this reason, it is often best to consult an expert for brake repairs.

Professional mechanics have the knowledge, experience, and specialized tools necessary for many kinds of repairs under the hood, including those associated with brakes.

RepairSmith is a convenient mobile vehicle maintenance and repair service that provides quality brake repair services at your doorstep.

With RepairSmith, you don’t have to worry about sourcing parts or spending time in waiting rooms while your car is worked on – they do all this for you. And thanks to their easy online booking process, repairing your brakes is simpler than ever.

Frequently Asked Questions [FAQs]

1. What Is A Brake Warning System?

A brake warning system is a safety feature in many vehicles that alerts the driver when there is a brake issue. The system has a dashboard light and/or audible alarm that turns on when something is wrong. The brake warning system monitors your vehicle braking system’s hydraulic pressure, temperature, and other parameters to detect potential problems. If it senses any abnormality, it will alert the driver through a warning light or alarm.

2. What Could Cause A Brake Warning Light To Come On?

Several issues, such as low brake fluid levels, faulty brakes, worn-out pads, etc., can trigger a brake warning light. It’s important to have your vehicle inspected by a certified mechanic if the light comes on so that they can properly diagnose and repair the issue.

3. How Often Should I Check My Brakes?

It’s recommended to have your brakes inspected by a certified mechanic every 6 months or 6,000 miles. During these inspections, your brakes should be checked for any signs of wear, damage, or other issues. It’s also important to keep an eye on your vehicle’s brake fluid levels and top it up as needed.

4. What Module Controls The Brake Lights?

The brake lights are controlled by the central body control module (BCM), a computer system that monitors and controls many of the vehicle’s functions. The BCM uses input from various sensors to determine when the brake pedal has been pressed and then sends a signal to power the brake light circuit. When the driver presses on the brakes, the BCM will signal to turn on the brake lights.

5. Where Is The Brake Light Sensor?

The location of the brake light switch can be found under the dash near the top of the brake pedal. It is typically secured to a small bracket and activated when the pedal is pressed.


Diagnosing and repairing a brake warning light can be a bit tricky. However, with the right knowledge and tools, it is possible to make an accurate diagnosis and safely get your vehicle back on the road. If you’re uncomfortable tackling this job yourself, it’s best to consult an expert mechanic with the specialized tools and experience required for brake repairs.

John D. Archer

John D. Archer is a mechanical engineer and writer based on the area of automotive accessories at, A resident expert and professional, John is passionate about all things automotive and loves to share his knowledge. He has good experience in all kind of automotive accessories. He has worked as a chief mechanical engineer in some reputed automotive garage firm.