You pull into your favorite spot when a warning light with a ‘P’ symbol flashes on your dashboard. Your mechanic says it indicates a parking brake malfunction.
But what does this error mean, and what causes it?
Parking brake malfunction means that the parking or emergency brake — which keeps your vehicle stationary when parked — isn’t engaging. While this can be serious, especially on hills or inclines, there’s no need for immediate panic.
In this article, we’ll cover the causes of a parking brake malfunction, what to do when the light comes on, and how to reset it safely.
This Article Contains:
- 12 Common Causes of Parking Brake Malfunction
- 3 Crucial Steps to Take When Your Parking Brake Malfunctions
- How to Reset the Parking Brake System Warning
- How Can You Prevent Electric Parking Brake Issues?
- 4 FAQs about Electric Parking Brake Malfunction
12 Common Causes of Parking Brake Malfunction
A range of issues can cause a parking brake malfunction, such as:
- Faulty or dirty parking brake button: Dust, crumbs, or debris can accumulate behind the button over time, preventing it from activating fully. This will trigger the system to display a warning light.
- Low battery voltage or power issues: An electric parking brake (EPB) relies on stable voltage and power from the battery to function correctly. An electrical issue, like a weak battery or damaged wiring, can lead to a parking brake failure, triggering the warning.
- Malfunctioning electronic control unit (ECU): If the ECU fails due to an electrical issue like low voltage, the electronic parking brake system won’t engage efficiently. This can turn on the dashboard warning.
- System not reset after repairs: If you recently serviced the rear brakes but skipped resetting the electronic parking brake, the system might detect abnormal behavior and activate the light.
- Faulty sensors: The electronic parking brake relies on sensors to monitor brake engagement, position, and hydraulic pressure. If one of these sensors malfunctions, it can trigger a warning even if there’s no parking brake problem.
- Failed or jammed servo motor: The electronic parking brake uses an electronic motor (servo motor) to activate the brake. If the motor seizes or doesn’t respond to commands, you’ll have a parking brake failure.
- Worn brake shoes or pads: If the brake shoes or pads in the rear wheels are too worn, they can’t provide enough friction to hold the vehicle properly. In the electric parking brake system, the sensors detect this problem with engagement, turning on the warning message.
- Broken return springs: Return springs are essential for pulling the brake shoes or pads away from the drum or rotor after release. Damaged springs prevent the brakes from disengaging fully, prompting the warning.
- Seized calipers or internal mechanisms: Calipers or other brake components may get stuck due to a lack of use. When the electronic parking brake system detects that the brakes aren’t fully engaging due to mechanical resistance, it’ll flag a parking brake failure message to alert you.
- Cable wear: If the parking brake isn’t used regularly, the cable can become stiff or accumulate rust. When this happens, the brake might not engage and trigger a parking brake malfunction warning.
- Brake fluid issues: A low brake fluid level or contaminated liquid can prevent the electric parking brake from engaging smoothly. Once detected, the parking brake module will activate the dashboard light indicating a parking brake problem.
- Other system malfunctions: Broader issues like ABS (Anti-lock Braking System) or master cylinder faults can impact electronic parking brake operation and set off the braking system warning.
The parking brake warning can appear at any time, regardless of the root cause, so it’s essential to be prepared to handle the situation safely.
3 Crucial Steps to Take When Your Parking Brake Malfunctions
Here’s what you should do when the parking brake warning comes on:
- Pull over safely: Stop in a safe spot like a road shoulder or a nearby parking lot.
- Disengage the parking brake: Ensure the parking brake lever, brake pedal, or electronic switch is fully released.
- Restart the car: Turn the car off and on again. If the warning light turns off, it might have been a minor glitch.
Sometimes, the warning light can stay on despite restarting the car. In such cases, call a tow truck or a qualified mechanic to fix the parking brake mechanism and reset the warning.
Let’s see how they’ll do that.
How to Reset the Parking Brake System Warning
Resetting the parking brake warning involves working with your vehicle’s electronic system. If you’re not sure, hire a qualified mechanic to handle it for you.
Here’s what they’ll do:
- Turn off the engine and open the hood.
- Find the negative battery terminal (usually marked with a minus sign) and disconnect it using a wrench.
- Wait for a few minutes to let the system fully power down.
- Reconnect the cable, tighten it, and close the hood.
- Start the vehicle and check the dashboard to confirm the warning isn’t on.
If the warning stays on, the mechanic will connect a scanner to read the error code, find the root cause, and repair it.
But, you know what’s better than fixing?
Preventing the damage!
How Can You Prevent Electric Parking Brake Issues?
A few ways to maintain a healthy parking brake system are:
- Use the parking brake regularly: Engage and release the parking brake often to keep the cables moving. This helps prevent rust and corrosion, especially if you don’t drive your vehicle daily.
- Inspect the parking brake cable: Have a mechanic check the parking brake cable and replace it if it shows signs of corrosion.
- Check the lever, brake pedal, or button: Whether your car uses a manual parking brake lever or an electronic switch, make sure it works smoothly. If it feels loose, sticky, or has debris, swap it out before it fails.
- Adjust the parking brake system properly: Follow your vehicle’s inspection schedule to keep the brakes adjusted. If they’re too loose, they won’t grip the wheel firmly enough to hold the car or truck. And if they’re too tight, they can cause the rear wheels to drag while driving.
- Maintain brake components: A worn brake pad or damaged rear brakes can cause the parking brake module to fail. Ensure regular maintenance of the brake parts to prevent this.
Have more doubts regarding your parking brake?
Keep reading to find the answers.
4 FAQs about Electric Parking Brake Malfunction
Let’s look at some questions vehicle owners frequently ask about parking brakes:
1. How Can You Tell If Your Parking Brake Is Malfunctioning?
When facing a parking brake issue, you’ll notice:
- Dashboard light or message: A warning light or message is one of the clearest indicators of a parking brake issue. This usually appears as a flashing or steady “P” symbol or “Parking Brake Fault.”
- Brake won’t engage or release: If you press the electric parking brake button, but the brake doesn’t engage or release as expected, this signals a problem. You might hear a clicking sound, or the vehicle may roll even though the brake is engaged.
- Unusual noises when using the parking brake: If you hear grinding or clicking sounds often, it indicates a failing actuator, stuck motor, or damage within the electronic parking brake mechanism.
2. How to Disengage an Electric Parking Brake?
Usually, you’ve to press the parking brake switch and brake pedal to disengage the emergency parking brake. However, in modern vehicles, the EPB system also allows automatic release, which works only when:
- The accelerator pedal is pressed
- The seat belt is fastened
- The bonnet, trunk, and driver’s door are closed
- The car is in reverse (R) or drive (D) mode
3. Is It Safe to Continue Driving with a Malfunctioning Parking Brake?
No, it’s not safe to drive with a failing parking brake.
The emergency brake keeps your car stationary when parked. If it malfunctions, the vehicle could roll, putting people at risk.
In most states, vehicle owners can also be held liable for driving with a known brake issue, especially if it leads to an accident. So, it would be best to call a mobile mechanic to fix this problem ASAP.
4. How Much Does It Cost to Fix a Malfunctioning Parking Brake?
Fixing a malfunctioning parking brake typically costs between $100 and $500, depending on your car model and the severity of the issue.
Fix Parking Brake Issues with AutoNation Mobile Service
A malfunctioning parking brake system puts both you and others at risk, as the vehicle may not stay securely parked. It could also indicate a deeper brake system issue that needs immediate attention.
No matter the reason, AutoNation Mobile Service can help!
We offer mobile auto repair and regular maintenance services, like sensor or brake pad replacement, right at your location. We’re available seven days a week and offer a 12-month, 12,000-mile warranty on all repairs.
Book your slot so you can park safely anywhere, anytime.