When the “service brake assist” warning appears on the dashboard, the brake assist system is faulty. It’s possible that the vacuum pump is bad and needs to be tested for suction. In this case, it needs to be replaced and its components reassembled.
The system uses sensors to detect when the driver applies brakes and does not apply the full amount of pressure needed for a safe stop.
The service brake assists light will turn on when the vehicle is driven at speeds above roughly 10 miles per hour (16 kilometers per hour), but this is not to say that it can’t also come on while driving at low speeds if there’s an issue with the system.
Common Reasons for the “Service Brake Assist” Light
1. Low Fluid
The service brake assist light comes on if you have low brake fluid or if a component in your braking system fails. This is because when there’s not enough fluid in the system, it can affect the operation of the ABS valve and reduce the effectiveness of your brakes.
Low fluid levels can also cause pedal sponginess and make them feel soft, which reduces driver confidence and increases stopping distance.
2. Wiring Issues
Wire harnesses and/or wiring harnesses may be damaged as a result of corrosion, which can happen when moisture gets into the electrical system and causes corrosion. This can result in wires that are loose or broken, which in turn affects the proper operation of your vehicle’s braking system.
3. Faulty Brake Booster
Your car’s brake booster works in conjunction with the master cylinder, which has a piston connected to a flexible tube.
When you press on your brake pedal, the piston pushes back against this flexible tube and this creates resistance that causes your foot to apply more force on the brakes when you step down on them. The piston is pushed by a vacuum created by the engine’s intake manifold (which is just air being pulled into the engine).
When there’s no vacuum, or if there’s not enough vacuum to provide enough power for braking, then your car will automatically activate its ABS (anti-lock braking system) to compensate for this lack of power.
This means that when you step on your brakes very quickly after turning out of an intersection or avoiding an obstacle in front of you, like an animal crossing into traffic. Your vehicle will still stop even though it needs more force applied from inside than from outside due to lessened power supplied by the brake booster itself.
4. Vacuum Leaks To The Brake Booster
Vacuum leaks to the brake booster are a common cause of failed and/or non-functional vacuum boosters. If there’s a leak, your car’s ABS will not function properly and it may be difficult to control the vehicle. This can cause you to lose control of your vehicle or lead to an accident.
Leaks in the brake booster can also cause overheating as well as the failure of other components like wheel cylinders and master cylinder pistons.
5. Worn Brake Pads
Brake pads are an important part of your braking system and can wear out over time. If this happens, it could compromise the effectiveness of your vehicle’s brakes and create a dangerous situation for you or other drivers on the road.
How To Fix Service Brake Assist
1. Reading The Trouble Codes
Reading the trouble codes on your vehicle is a good way to start figuring out what the problem might be. Trouble codes are stored in a computer inside the vehicle, and they can provide some insight into what’s going wrong with it.
Trouble codes are not always accurate, so don’t rely on them too much when diagnosing problems on your car or truck. It’s important to know that you should never disconnect any electrical components from the battery while troubleshooting for this reason: if you do, you could cause damage to yourself or others.
2. Check Your Brake Pressure Sensor
The brake pressure sensor is located on the top of your rear axle. It controls how much power gets to your brakes and can be replaced by either a shop or by yourself.
To replace it yourself, remove the tire and wheel from the rear axle, remove the dust cap from behind where your tire was, and unscrew two nuts that hold down each side of that area (you’ll only need to remove one nut on each side).
Once you’ve done this, you can take out the old sensor with pliers or vice grips so you can install a new one in its place.
3. Replace Your Brake Boosters
The brake booster is a vacuum pump that helps your brakes work. It is located behind the dash, and it’s part of your vehicle’s braking system. It works with the master cylinder to provide power to the brakes.
The proper operation of this vacuum pump requires a series of connections, including hoses and even a switch inside the truck cab’s center console. Faulty connectors or loose hose clamps can cause problems like poor braking feel or even no ability to stop at all.
Is It Safe to Drive With The Service Brake Assist Light?
The service brake assist warning light is a normal part of your vehicle’s operation. It does not mean there is anything wrong with the system.
If you see this light on, there may be some dust or sand in the sensor. This can happen when driving in dusty conditions. (You can prevent this by installing a sensor guard).
If you have driven through snow and mud recently, they could also be causing problems with the sensors. The only way to know for sure what’s causing it would be to take it to a mechanic and have them check out your brakes and sensors.
How Important is The Brake Assist System?
The brake assist is a system that helps you avoid a collision when you need to stop quickly. It can also prevent loss of control or even a rollover. If you have a vehicle that doesn’t have this feature, it’s important to know how it works.
If the Vehicle Stopping Distance Chart shows that your vehicle takes longer than other vehicles to stop, then brake assist might be helpful for you. Knowing how the brake assist works and what its limitations are can help keep you safe on the road.
The brake assist helps you stop your vehicle faster and with more control. It’s important to know what this feature does and how it works, as well as when it might not be working correctly.
By having an understanding of how to troubleshoot the issue and what steps need to be taken for everything to work properly again, you can save yourself from getting stranded somewhere unsafe or even worse causing an accident.
The service brake assist light can come up due to the following reasons: low fluid, wiring issues, faulty brake booster, vacuum leaks to the brake booster, and worn pad brakes.
If you’re wondering whether or not you can turn off your vehicle’s service brake assist warning light, the answer is yes. You can do this by resetting the light, reading the trouble codes, replace the worn pads and the faulty brake booster. Once, you’ve done all this, you can peacefully enjoy your ride.
Ugo is a passionate car enthusiast with a Bachelor of Electrical and Electronics Engineering degree and hands-on experience in troubleshooting and fixing automobiles.
I combine my electrical and mechanical engineering knowledge with practical skills to address car-related issues.
My love for cars and dedication to educating others led to the creation of Fixandtroubleshoot.com!