Toyota Prius Brake Light And ABS Light On

Why Toyota Prius Brake Light And ABS Light On? Know the reasons!

The warning lights for the brakes and ABS in the Toyota Prius are one area that needs attention. These lights can be illuminated for several reasons.

So, why is the Toyota Prius brake light and ABS light on in particular? There are numerous causes involved. A few of them, such as a faulty warning light switch, faulty ABS sensor, or low battery voltage, are typically responsible. Some issues are very specific, such as a bad ABS module for the ABS warning light or low brake fluid for the brake light, among others.

Here, we’ve covered every typical issue that frequently affects both brakes and ABS. Along with that, we offer some simple ideas for solutions to each problem.

What Does It Mean to Have the Brake Light and the ABS Light On?

The brake light and ABS actually represent two distinct things. Brake lights simply indicate that there is a problem with the vehicle’s core braking system. 

What Does It Mean to Have the Brake Light and the ABS Light On

Contrarily, ABS stands for an anti-lock braking system and is entirely managed by an automatic control module. So the problems with ABS are different than brake issues.

The light indicates that there are problems because flashing is taking place. In that case, you must drive your vehicle to the nearest service station, or you may hire a professional to troubleshoot and resolve the issue.

What Are The Causes And Solution Of Toyota Prius Brake Light On

Differences exist between the causes and solutions for problems with the brake and ABS lights. Some problems are only detrimental to the braking system, while others are only to blame for the dysfunction of the ABS brakes.

Causes And Solution Of Toyota Prius Brake Light On

Here are some potential causes and fixes for your brake light issue.  Let’s examine them.

1. Low brake fluid

If your braking system’s fluid level is not optimal, it will begin to warn you by flashing lights. You must access the reservoir tank, which is located under the hood, to check the fluid level in your brake system. You will undoubtedly receive a warning when the fluid level is low. 

If your fluid reservoir has any leaks, in addition to the fluid level, it also warns you through lights.


The appropriate amount of fluid leveling is required. And while a leak can be fixed, replacing it is a good idea if the damage is extensive. Here is what you do:

1. Begin by reaching into your fluid reservoir.

2. Visually examine the fluid level.  Make sure the recommended range is ideal. If it’s low, raise it up by adding more liquid.

3. At this point, look for any indications of a lean, wet spot, or fluid leak. Bring your vehicle to a service shop if any damage or leaks are discovered. Because these are pretty hard to fix at home.

2. Worn Brake Pads

If the brake pads are worn out, it can cause the brake light to come on. This indicates that the pads need to be replaced to maintain proper braking performance.

Toyota Prius Worn Brake Pads


Here is how you can install the

Step 1: Place your Toyota Prius in a flat area, press the parking brake, and gather the required equipment. For example: lug wrench, C-clamp, socket wrench, etc.

Step 2: Get rid of the worn brake pads. Loosen the lug nuts, use a jack to lift the vehicle, remove the wheel, and look for the brake caliper.

Step 3: Install the new brake pads. The caliper piston should be compressed using a C-clamp or brake caliper tool. Replace the old pads before putting the brake caliper and wheel back together.

3. Parking brake set

The brake lights may continue to illuminate if the parking brake, also known as the handbrake, is not fully released. When parked, the car is kept still by a separate mechanism called the parking brake. The dashboard brake light may turn on if the parking brake is even partially applied.

Read:  Ford Explorer ABS Light On: Common Causes and Resetting Solutions


You need to release the brake appropriately in order to turn off the signal lights. This is not a severe case but happens frequently.

4. Brake light switch issues

In some instances, even though your brakes are flawless, your warning light may be on as a result of a poor switch adjustment. It indicates that there is a problem with your brake light switch because it is on. If it’s not the switch adjustment, bad wiring is also to blame for this issue.

Toyota Prius Brake light switch issues


Here is how you should adjust the brake light switch:

Step 1: Make sure the brake light switch is adjusted by making sure it is correctly positioned and turns on when the brake pedal is depressed.

Step 2: To ensure proper contact with the brake pedal, reposition the switch if it is out of alignment.

Step 3: If adjusting the switch does not solve the problem, check the wiring for any damage or faulty connections and make the necessary repairs. (Since it can be challenging for non-experts to check for wiring damage, you are advised to hire a professional for this.) 

As a novice, you can quickly check for faulty wiring by doing these two things:

  1. Visually inspect the wiring straps for any visible damage, such as burning or frayed wires.
  2. The wiring connectors should be gently tugged to make sure they are firmly fastened to the appropriate components.

What Are The Causes And Solution Of Toyota Prius ABS Light On

Causes And Solution Of Toyota Prius ABS Light On

The following are some possible causes and solutions for your ‘ABS light on’ problem. Let’s investigate them.

1. Low Battery voltage

If the battery voltage is not enough to power the ABS system, the ABS light might turn on. This could happen if the electrical system or alternator malfunctions, resulting in low voltage. 

It’s crucial to check the alternator and electrical system for proper operation when dealing with battery-related issues.


Try troubleshooting the battery; if it can be fixed, do so; if not, replace it.

Step 1: The battery is in the back of the car; just lift the hood to access it.

Step 2: Remove the battery’s positive (+) and negative (-) terminals one after the other.

Step 3: Remove any retaining brackets or clamps that have been used to keep the battery in place.

Step 4: Install the new battery and secure it with retaining brackets or clamps before reconnecting the positive (+) and negative (-) terminals.

Aside from that, if you have a problem with your alternator or electrical system, you should hire a professional to troubleshoot and repair it.

2. Bad ABS module

When your ABS is working properly but you keep getting the warning light, you should check to see if your ABS module is functioning properly or not. When a module has a problem in such circumstances, you might not immediately notice it. 

Toyota Prius ABS module


To resolve this issue, you must first repair the ABS module system. Here is what you can do quickly in order to fix the ABS module system.

Step 1: Use a scanner or diagnostic tool to look for error codes in the ABS module.

Step 2: Examine the wiring and connectors for any signs of damage, loose connections, or corrosion.

Step 3: Disconnect the battery and then reset the system. Wait for a few minutes, and then reconnect it.

3. A broken wheel speed sensor

The ABS light might come on if a wire connecting to the wheel speed sensor breaks. It also happens when there are issues with the ABS module system. But mostly, it’s the wheel speed sensor rather than the ABS system itself. This interferes with the sensor’s ability to communicate with the ABS system, which affects the system’s ability to precisely track wheel speed.

Read:  ABS Light On After Tire Blowout: (Knowing The Causes And Fixes!)


Check the wires connecting the wheel speed sensors for damage or disconnection. In order to get the ABS system working again, fix or replace the damaged wire and make sure the connections are secure. If that’s not the case, troubleshoot the ABS system.

4. Bad wheel bearing

Your ABS warning light may illuminate if your issue is with a wheel, or more specifically, a wheel bearing. Particularly when the wheel bearing is severely damaged or worn out, it becomes a problem. The system discovers that the ABS system is unable to read the wheel speed reading properly.

Toyota Prius Bad wheel bearing


The simplest solution to this problem is replacement. Here is how you can replace the bearing in your Toyota.

Step 1: The vehicle should be raised and secured with jack stands in the first step.

Step 2: A wheel bearing assembly can be accessed by removing the wheel, brake caliper, and rotor

Step 3: Finally, swap out the damaged wheel bearing for a fresh one, put everything back together, and then lower the car.

If you’re facing brake light and ABS light issues in your Toyota Prius, you may find our article on how to turn off and reset ABS light helpful. This article provides step-by-step instructions to address ABS light concerns, which may assist in resolving the brake light and ABS light issue in your Toyota Prius. Additionally, if you’re interested in learning about ABS light problems in a BMW 328i, you can check out our article on BMW 328i ABS light on for insights and potential solutions specific to that model.


Here are a few of the frequently asked questions regarding “issues with the Toyota Prius brake light and ABS light on.” 

1. How do I read the brake/ABS trouble codes without OBD?

It is possible, but not very effective, without OBD. What you need to do is run a short wire between the OBD connector’s TC and CG terminals. The next step is to count the flashes of light. 

2. How much does diagnosing a brake light or ABS light problem on a Toyota Prius cost?

It is determined by the state and the service center. While hiring a professional and diagnosing generally cost $60 to $120, there are exceptions. However, if any parts require replacement or repair, they will be charged separately. 

People who had these problems resolved by service centers paid a total of around $300, which included everything.

3. Is it safe to operate a vehicle while the brake and ABS lights are on?

The warning light indicates that there is a problem with the brake, so it is best to take the safest course of action since you are unsure of what exactly occurred.

Driving while you have a warning light, especially one for your brakes, is strongly discouraged by experts. Driving while having these problems can be extremely risky. However, if you want to drive your car to the service center, you can do so as long as you ride cautiously and slowly. 

Final Words

If both the Toyota Prius brake light and the ABS light are on in your vehicle, it indicates a potential braking system problem. This could be due to issues such as low brake fluid, a faulty ABS sensor, a malfunctioning ABS module, a broken wheel speed sensor, etc. Your car’s performance and safety could be threatened if you ignore these warning lights. The majority of the solutions to the problem have been provided, but not all of them are doable at home. 

For a few issues, you should seek professional assistance from an authorized Toyota service center or a qualified mechanic.

Leave a Reply

Your email address will not be published. Required fields are marked *