Brake Fluid Light On But Fluid Is Full (Troubleshooting Guide)

Are you dealing with the issue of the brake fluid light coming on despite the fluid being perfectly full? If yes, you may be wondering what all this means and how you can fix it. Rest assured that this guide will help you fix this problem.

Brake fluid light on but fluid is full can be caused by a faulty brake fluid level sensor, bad brake fluid, worn-out brake pads, issues with the master cylinder, or electrical issues. Having your car diagnosed by a mechanic helps pinpoint the exact cause of this problem.

This article will discuss all the potential causes of brake fluid light coming on even when the fluid is full and what you can do in such a situation. We’ll also discuss how to turn off the brake warning light and other helpful info.

Why Is Your Brake Fluid Light On But The Fluid Is Full?

Your brake fluid light on but the fluid is full can be caused by different issues. Below, we have discussed the most common causes of this problem:

Contaminated brake fluid

Over time, brake fluid can become contaminated with debris, moisture, air bubbles, etc. All these undesired elements end up affecting your car brake system’s proper functionality. Consequently, this leads to the low brake fluid light coming on.

In this case, you’ll need to flush all the contaminated brake fluid and replace it with a new one. Replacing your brake fluid regularly as recommended by the owner’s manual can also help ensure it doesn’t deteriorate over time.

Faulty brake fluid level sensor

The brake fluid level sensor monitors the level of brake fluid in your car’s brake system. If this sensor gets damaged or starts malfunctioning, it can send the wrong signals to the dash.

This causes a low fluid warning light to come on even when the fluid is at recommended levels. The best way to resolve this issue is to replace the faulty sensor.

Electrical or wiring issues

The wiring harnesses connected to braking system can get shorted or worn out. The brake system fuse can also burn out.

If any of this happens, it can trigger the brake fluid level on your dash regardless of the amount of brake fluid in the reservoir.

Moreover, if the brake light bulb is blown, it may also cause the brake warning light. You should have your car inspected for electric and wiring issues and any defective components replaced.

Worn-out brake pads

Brake pads make a crucial part of your car’s braking system. Therefore, if they start malfunctioning, due to normal wear or damage, they’ll definitely affect your vehicle’s braking performance.

This is another likely reason for the brake fluid light popping on. Brake pads related issues can greatly compromise your safety, so it’s important to have them fixed as soon as possible.

Faulty ABS (anti-lock braking system)

A brake fluid leak or mechanical defect can cause the malfunction of your car ABS system. This can potentially activate the low brake fluid light.

We advise you to maintain your car ABS system and have any necessary repairs done to it as soon as possible.

ABS system repairs might be a bit complex, so you’ll definitely need a qualified auto mechanic for the job.

What To Do If Your Car Brake Fluid Light Comes On

In this section, we’ll discuss some helpful diagnostic tips to help you identify the source of the problem brake fluid light comes on but the brake fluid is full.

• Inspect your car sensor: You’d want to start by checking if your car brake fluid sensor is malfunctioning. If you don’t know how to go about it, let a certified auto mechanic inspect it for you and replace it if necessary.
• Check the brake fluid status: Typically, your car brake fluid should be clear, with a yellow (honey-like) tint. If it appears dirty (i.e., dark brown or black), get a professional to flush and replace it for you.
• Inspect your car for brake fluid leaks: Check if your car has any signs of brake fluid leaks and have it fixed by a mechanic before it can get worse.
• Check brake pads: Worn-out brake pads can also trigger the light, so you should inspect them as well for excessive wear. If they have gone below recommended thickness, we advise you to replace them promptly.

If you’ve checked all the above areas and you can’t find the problem, we advise you to seek assistance from a certified auto mechanic. The auto shops will use their expertise plus specialized tools to quickly find the underlying problem and fix it for you.

How Do You Turn Off The Brake Warning Light?

The best way to turn off the brake warning light is to resolve the underlying issue that caused it to come on.

Start by verifying your car brake fluid. If it’s still within the recommended level, go ahead and check if it looks contaminated. If it’s bad, you should have it flushed as we mentioned above.

Inspect your car for brake fluid leaks, replace any worn-out brake pads, and address the brake fluid sensor issues.

In most cases, once you have the underlying issue addressed, the light automatically clears on its own.

If it doesn’t go away in your car, you can try resetting it by disconnecting your car battery for a few minutes and then reconnecting it.

This trick usually resets all your electronic systems including the warning lights. It may even reset the clock settings and radio presets.

Here’s a video explaining how to turn off the brake warning light on your dash:

Video:

Why Low Brake Fluid Light Came On And Went Off?

If your vehicle’s low brake fluid warning light just came on and went off, it could be simply the car’s initial system check and nothing to worry about.

This check usually happens when you start your car and all the lights on your dash briefly illuminate as the car ascertains that everything is running fine.

If the light goes off briefly after the engine starts, that’s just normal behavior and nothing to freak about. It means the car has found no issues with your braking system.

However, if the light goes on and off while driving, it is likely caused by temporary fluctuations in the brake fluid level. The fluid might have fallen below the recommended level, triggering the warning light.

When it goes back to the correct level, the light went off. Slight movements of your car or changes in temperature can lead to these fluid fluctuations.

Faulty sensor or issues with wiring e.g. damaged or lose wires can also lead to intermittent activation of brake fluid light. For instance, the sensor or wire may briefly lose contact or undergo intermittent fault, causing the light to illuminate and then go off.

Presence of air bubbles in brake system can also make the brake lights come on temporarily. This is because the bubbles lead to fluctuations in brake fluid levels, thus activating the light.

What Causes Brake Fluid Warning Light On Mercedes?

The brake fluid warning light on your Mercedes can be caused by several factors such as low brake fluid level, contaminated brake fluid, a leakage in brake system, faulty brake fluid level sensor, and issues with brake system wiring.

When the fluid warning light on your Mercedes comes on, we advise you to address the issue immediately to ensure optimal performance of your brake system.

Seek the help of a qualified technician or authorized Mercedes servicing centers for accurate diagnosis and fixing of the underlying problem.

What Does The Brake Fluid Warning Light Ford Fiesta Mean?

The Ford Fiesta brake fluid warning light indicates your brake system has a problem that needs your attention.

Some of the most common issues that could trigger the light include low brake fluid level, a leak in the system, worn brake fluid, or the need for brake fluid change.

When this happens, you should have your car diagnosed and the underlying issue resolved promptly.

This is important as issues with your brake system can greatly compromise your safety on the road as well as that of other road users.

Why Does Low Brake Fluid Light Come During Cold Weather?

The low brake fluid light may also come on during cold weather. This isn’t something unusual. Cold temperature tends to affect your brake system and fluid in different ways.

For instance, there could be moisture in the brake fluid that freezes in cold weather, causing the brake fluid to contract. This leads to a temporary drop in fluid level and the low brake fluid light gets activated. However, the light may go off after the liquid warms up and expands.

Extremely cold temperatures may also interfere with brake pads performance. The pads’ effectiveness may reduce until they warm up again and their optimal friction is restored.

The temporary interference of pad performance can lead to increased brake system pressure. This leads to a drop in fluid level and the low brake fluid light comes on.

In cold weather, various brake system components such as hoses and rubber seals may get more rigid, bringing about the possibility of small seepage or leaks. The result is decreased fluid level and the brake fluid light illuminating.

Can You Drive With Brake Fluid Light On?

We advise against driving your car with brake fluid on. As we’ve already discussed before, this warning light is usually a sign that your car could be experiencing multiple issues with your brake system.

Ignoring it can put your safety at risk. It can eventually lead to damage to brake system component, reduced braking system performance, and even brake system failure, which increase the risk of accidents.

If the light comes on while driving, we advise you to safely pull over and inspect your car for the cause of this light.

Check the brake fluid level and for contamination, inspect your car for visible leaks. Have a certified mechanic diagnose and resolve the problem your car is experiencing before you can get back on the road.

If you’re experiencing the brake fluid light on but the fluid level is full, you may also find our article on brake light on dashboard goes on and off helpful. This article explores potential causes and solutions when the brake light on the dashboard illuminates intermittently. Additionally, if you’re facing a situation where the brake light stays on even when the car is off, our article on brake light stays on when car is off provides insights into possible reasons and troubleshooting steps.

FAQs:

Why does my car say low brake fluid when it’s full?

Your car indicates low brake fluid when the fluid is full due to issues like a faulty brake fluid level sensor, contaminated brake fluid, and electric system or wiring issues. Have your car diagnosed by a qualified technician to find out the exact trigger behind the light.

How full should brake fluid be?

The brake fluid should be at the “Max” or “Full” level indicated on your vehicle’s brake fluid reservoir. Avoid overfilling or underfilling the reservoir as this can affect your brake system performance.

Why does my brake fluid light keep coming on?

Your brake fluid light keeps coming on due to various issues such as low brake fluid level, leaks in brake system, faulty sensor electrical, or wiring issues.

Conclusion

When your car dash illuminates with the brake fluid light despite the fluid being full, there are several potential causes to consider. These include a malfunctioning brake fluid level sensor, bad brake fluid, electrical system or wiring issues, worn-out brake pads, and a faulty ABS system. Generally, the light coming on indicates a problem with your brake system.

We don’t recommend driving your car with the low brake fluid warning light. Instead, you should safely pull over and have your car diagnosed and resolved by a qualified mechanic. Attempting to drive your car with the warning light risks damage to your brake system component, brake system failure, and increased risk of accidents.