Service Brake Assist – What Does It Mean? Everything To Know

Service Brake Assist is a newly launched safety feature that most of the latest car owners want to learn about. Most times, drivers find themselves in situations where their reaction times and the force that they apply to the brake pedal may not be sufficient for a sudden quick stop or sometimes to avoid a crash.

Service Brake Assist

Thanks to technological advances, the service brake assist system helps to further assure many drivers’ safety. In this guide, we will detail all you need to learn about the service brake assist, including the significance of the warning light, what to do if it is on, and the steps to reset it.

What Is the Meaning of Service Brake Assist in Vehicles?

The meaning of service brake assist, also called emergency brake assist, is an automated feature of the modern vehicle braking system that augments braking pressure during emergency braking. The brake assist system’s intervention helps vehicles to stop faster, which further ensures the safety of drivers by preventing collisions or crashes.

– Brake Assist System

The brake assist system is designed to enhance the efficiency of the braking operation of vehicles by generating additional brake pressure sufficient to cause a quick stop. Likewise, this system is not meant to replace the regular braking operation but rather to complement the operation of other components such as the Anti-Lock Braking System (ABS) as well as the Traction Control System (TCS).

The system is mainly found in modern vehicles as an innovative approach to improve safety, especially during emergencies. Regardless, there are still a few discrepancies among drivers about the performance and efficiency of the brake assist system. While some assert that this safety feature interferes with the regular braking system, others opine that the brake assist system makes it challenging to fully control the impacted vehicle without sudden and undesirable stoppages while driving.

Consequently, several car owners trust that it is best to disable brake assist system to relish a much more normal driving using the regular braking system that allows them full control of the vehicle. Based on data accrued, studies have shown that the brake assist system has helped avert more avoidable road crashes than ever before. Therefore, understanding how the brake assist system operates or functions will give you more insights into the benefits and importance of this brake feature.

– How It Works in Modern Vehicles

Typically, the brake assist system comprises several sensors combined with computer software within the vehicle to detect when a driver’s motion requires enough braking power to stop quickly. These system sensors’ programming and design capabilities can monitor a driver’s typical driving style, particularly the consistency of engaging the brake system by measuring the pressure applied to the brake pedal within a certain period.

So when the system detects a sudden change or irregularity in the brake system application, it releases additional braking force to shorten the braking distance and ensure more effective braking.

For instance, if you’re in a situation where you haven’t fully pressurized the brake pedal and the system detects that a quick stop is necessary, the brake assist system automatically activates and releases extra hydraulic pressure into the brakes. As such, the additional braking force released helps shorten the braking distance for a quick stop, thus averting unexpected collisions or crashes. To crown all of this, this advanced safety feature can prevent accidents; therefore, it is safe to say that this innovation is priceless!

– Service Brake Assist vs ABS

While the ABS and brake assist features of a vehicle’s brake system seem to overlap, keep in mind that they both play different roles in helping drivers make safer stops. An anti-lock braking system (ABS) is a feature of a modern vehicle brake system that prevents the vehicle’s tires from locking in the case of an emergency stop. ABS makes your vehicle’s tires maintain a solid grip on the road track during difficult or sudden stops. More specifically, the system helps rapidly pump the brakes during a difficult halt to prevent the vehicle from sliding. 

Without the ABS, the wheel lockup can occur, making the driver lose control, with the vehicle possibly ending up careening dangerously out of control in a straight path. So preventing wheel lockup remains a vital safety feature for all automobiles. For instance, if you experience a situation that requires a sudden stop, the ABS gets activated and releases the brake pad intermittently to prevent the wheels from locking. As such, a moving or unlocked tire during an emergency stop enables the driver to steer freely and avoid hitting a potential hazard.  

Brake assist, on the other hand, helps augment braking force during emergency stops to ensure the vehicle stops faster. Take note that the service brake assist system is designed to supplement, not replace, the ABS. Simply put, the brake assist work alongside the anti-lock brakes to make sudden stops more effective and collision free.

What Are the Two Different Types of Brake Assist Systems?

The two different types of service brake assist systems include mechanical and electronic brake assist. The mechanical brake assist is the older variety, while the electronic brake system is the more recent version. Let’s take a closer look at them below:

What Are the Two Different Types of Brake Assist Systems

– Mechanical Brake Assist

The first brake assist system invented had mechanical features rather than the more sophisticated electrical variety now found in modern vehicles. The automatic brake assist comprises only mechanical components, implying that there are no electrical inputs to monitor the speed and force of the driver’s regular engagement with the braking system. 

Instead, the motorist controlling the vehicle must impact the brake pedal to a specific point before the brake assist system gets activated. When this occurs, the mechanical brake assist system activates a locking system which directs additional braking force to the brake booster instead of the brake piston valve to create a faster stop.

– Electronic Brake Assist

As the name suggests, the electronic brake assist system comprises an electronic control unit that uses electrical inputs to detect an emergency when the driver applies irregular pressure on the brake pedal. Thus, when the brake assistance system detects that the drivers thump the brake pedals to stop the vehicle as quickly as possible, the electronic control unit provides additional braking power to reduce braking distance even further. 

This brake assist system monitors, so when this deviates from the specified range, the electrical unit gets activated. Perhaps the most important quality of the electronic brake assist system is that the system is programmed to monitor the regular speed and force the driver applies on the brake pedal. 

Aside from this, the system’s preprogrammed thresholds can adjust to meet the braking engagements or force and pace of foot pressing over time. As a result, this system performs a more effective and efficient job of triggering and supporting the brake system when required in an emergency than the mechanical brake assist system.

What Are the Common Reasons for Activated Service Brake Assist Warning Light?

The common reasons for activated service brake assist warning lights include low fluid leveds, wiring problems, a defective brake booster, ABS malfunctioning, worn brake pads, and the warning light needs to be reset. When the warning light is activated in your vehicle, it is important to address the issue immediately.

Generally, the service brake assist system uses sensors to detect when a driver applies brakes in emergencies and thus provides the required additional braking pressure needed to ensure a safe stop. So, whenever the service brake assist warning light comes on, it indicates that the emergency brake assist system has detected a fault that needs immediate consideration. This warning light could indicate issues from bad sensors to abrupt speed changes, faulty hydraulic lines, or other crucial parts. 

You’ll find that this warning light indicator is situated at the center of the instrument cluster, usually to the right of the speedometer, making it very noticeable. For instance, depending on the vehicle model, the service brake assists light turns on sometimes when the driver exceeds a speed of roughly about 16 kilometers per hour, but this doesn’t necessarily mean that the warning light won’t come on while driving at low speeds if there’s an issue with the brake system. 

Here are some common reasons why the service brake assist warning light gets activated:

– Low Fluid Level

The service brake assist warning light gets triggered when your vehicle runs low on brake fluid or if the fluid fails to flow to another part of the braking system due to leakage or blockage. This is because it affects the operation of the Anti-lock braking valve. This, in turn, diminishes the effectiveness of the brakes. Aside from this, low brake fluid levels can also cause pedal sponginess. 

Low Fluid Level

Pedal sponginess occurs when air enters the brake lines and stops the brake fluid from flowing properly, making the brake pedal feel soft or spongy. Sometimes, this condition increases stopping distance during emergency stops, causing inexpert drivers to lose confidence. So once the light indicates an issue with the fluid level, you must flush or change the brake fluid as soon as possible.

– Wiring Problems

When corrosive elements such as moisture gain access to the electrical system, they often damage wire harnesses or wiring harnesses. This results in loose or broken wires, which impact the proper function of your vehicle’s braking system. As a result, the brake assist warning light comes on to alert you that there’s an issue with the brake system’s wiring.

– Defective Brake Booster

Your vehicle’s brake booster operates alongside the master cylinder, which comprises a piston linked to a flexible tube. By rule of thumb, when you thump on your brake pedal, the piston pushes back against the flexible tube to produce a considerable resistance that makes your foot apply more pressure on the brake pedal when you are trying to slow.

Defective Brake Booster

This is because the engine’s intake, which is just the air drawn into the engine, creates a vacuum that pushes the piston. So when there’s no vacuum or if there’s no vacuum sufficient to provide adequate power for braking, your vehicle will automatically activate its Anti-lock braking system to compensate for power shortage.

For example, your vehicle will stop if you step on your brakes swiftly after turning out of an intersection or attempting to avoid an obstacle. However, the lessened braking power from the defective brake booster that indirectly activates the ABS will trigger the service brake assist warning light to come on.

– ABS Malfunctioning 

In most cases, the anti-lock brake system dash signal gets ignited briefly when the ABS kicks in to help steer your vehicle in a slippery situation while on the road, but it turns off almost immediately. However, if the ABS light comes on and stays lit or starts blinking continuously, this indicates an emergency braking system issue.

A vacuum leak is a common cause of ABS malfunctioning that makes most drivers lose control of steering direction due to overheating while driving. Other issues that may trigger the ABS warning light include a damaged or contaminated sensor, a blown fuse, broken wiring, or a damaged controller.

Without a functional ABS, you’re prone to lose control of traction or experience wheel lockup, which could lead to an avoidable accident. Because of this, keeping and maintaining your vehicle’s brake system in top shape remains vital.

– Worn Brake Pads

Brake pads are a pivotal part of the braking system and wear out over time. When the brake pads get worn out, they tend to compromise the effectiveness of your vehicle’s brake system. Thus, this creates an unsafe condition for you or other drivers on the road. 

As a result, worn brake pads trigger the service brake assist warning light to come on. Many factors limit how long brake pads last after the brake assist warning light comes on, but take note that there’s a rough estimate of around 1600 kilometers of driving where efficient braking remains sustained.

– Warning Light Needs Reset

Typically, the service brake system dash light comes on to alert you of the issues with the braking system. However, in some cases, the lights malfunction, turning on or flashing for no mechanical reason. As such, it gets challenging to tell these two situations apart without a professional checkup.

Warning Light Needs Reset

So we strongly suggest you shouldn’t attempt to diagnose or reset your vehicle’s brake light by yourself. Instead, get a professional brake opinion from an auto technician to identify the problem’s source. 

How To Turn off Service Brake Assist Warning Light?

To turn off service brake assist warning light, you should first reset the light for the brake assist before anything else. This will help you clarify it the issue is a slight malfunction or an actual problem with the braking system.

In some cases, the warning lights, including the parking brake and traction light, illuminate the dash due to slight malfunctions or issues with their connection. As a result, some drivers panic when their GMC service brake assist light suddenly comes on. Instead of panicking, always maintain your cool and take the necessary precautions. 

Check the simple steps to turn off the service brake assist warning light below:

  1. Once you see the warning light, find a safe parking location and switch off the car engine.
  2. Lift open the hood, and detach the battery’s positive terminal cable.
  3. Afterwards, get back into the vehicle and step down the brake pedal for a few minutes until it drains the stored electricity.
  4. Now, you can rejoin the battery cable and restart the car.
  5. Then check the dash to confirm whether the brake assist warning light has been turned off. Once it’s off, you’re good to go.

Frequently Asked Questions

1. Can I Drive With Brake Assist and Traction Light On?

No, do not drive with brake assist and traction light on. In situations where both the ABS and traction warning light come on alongside the main brake warning light, it is not safe to drive such a vehicle until the issue has been resolved.

These warning lights indicate that your entire braking system is defective, so you may be unable to stop your vehicle when needed. Make sure to call an expert auto technician or have your vehicle towed to the repair store.

2. How Much Does Fixing Service Brake Assist Cost?

Fixing the service brake assist costs around $100 to $150, but generally, the total cost of fixing or replacing the service brake assist depends on your location and vehicle model. The service cost could increase depending on the auto technician’s charges. 

In addition, the average cost for replacing the brake booster falls anywhere between $325 to $1,250. But keep in mind that labor or service costs usually range from $100 to $200, and the vehicle parts’ cost varies.

3. How Do I Check the Effectiveness of Brake Assist System?

To check the effectiveness of brake assist system, first you must turn off the engine, then repeatedly pump the brake pedal slowly. After you pump it the first time, the pressure resistance from pressing the brakes should be low. As you continue pumping the pedal, the pressure resistance should rise.

The firmer grip indicates that the brake booster is not leaky and that the brake assist system is still in good shape. It is pivotal to check the effectiveness of your brake assist system evey once in a while. 


In this article, we extensively discussed what the service brake assist means in modern vehicles and its significance in further ensuring the safety of drivers. Here are some of the vital points we mentioned:

  • The service brake assist system is an automated feature of the modern vehicle braking system that enhances braking pressure during emergency braking. 
  • The mechanical brake assist is the older type, while the electronic brake assist is the newer version.
  • Low fluid levels, wiring issues, ABS malfunctioning, and worn brake pads are some common reasons why the service light for brake assist gets activated.
  • It’s best to consult an expert auto technician to diagnose the mechanical problem when the warning light comes on. 

The brake assist system is designed to improve your safety and alert you when there’s an issue with your braking system. Nevertheless, always keep a safe distance from the car ahead of you while you drive.

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