Parking brake unavailable car won’t start usually means a malfunction in the electronic parking brake system. It’s often caused by a weak battery or faulty components, preventing the car from starting.
Car dashboard messages can be confusing and frustrating. The message “Parking Brake Unavailable; Car Won’t Start” will certainly stress out most car owners. While there may be legitimate reasons to be concerned about the electronic parking brake (EPB) system failure from a safety and convenience perspective, the real concerning problem is that it is preventing the engine from starting.
In this article, we will explore the possible reasons your engine won’t start and possible solutions to this problem. We will explain the problem and offer potential solutions and preventative suggestions if your car will not start because of a parking brake malfunction.
Contents
The car computer is designed to improve your driving safety. It monitors many of your car’s electronic systems and controls to make sure they are operating properly. The message “Parking Brake Unavailable; Car Won’t Start” can be very frustrating and annoying, especially if your goal is to start driving as soon as possible. If you see this message, it suggests there may be a malfunction in the electronic parking brake (EPB) systems, and the car will not start until that issue is corrected.
The electronic version of the parking brake replaces the old manual handbrake lever. The lever is now a button that electronically engages and disengages the brake. The issue may simply be that the electronic systems designed to assist you with driving may be malfunctioning.
Simple reasons explain why the car won’t start. In this situation, the car’s computer system detects an issue with the parking brake, so the car won’t start to protect you. If the brake is not secured properly, or is broken, the car may roll away when it is parked. Or, the car may be stuck in drive.
It could even be something as simple as a weak battery, or it could be bad EPB system components. Let’s look into the possible causes and the best way to handle them.
When the warning stating “Parking Brake Unavailable” shows on the dashboard, it’s a warning stating that something is wrong with the electronic parking brake system and that is why the car won’t start. Most of the time, the issue is connected with the battery, sensors, or the control module, and this system is restricting the car from starting. You have to deal with this malfunction step by step in order to find the root of the problem.
1. Weak or Low Battery
A common reason for a car not being capable of doing a lot of things, including triggering the “Parking Brake Unavailable” alert, is a weak or dead battery. Modern vehicles rely on electrical systems for many critical functions, including ignition, and safety features like an electronic parking brake. If the battery is drained, it may not have sufficient voltage to engage or disengage the parking brake. This can result in an EPB system malfunction, and the car won’t start.
Effects on the Parking Brake System
A weak battery can cause the parking brake system to become non-functional. Consequently, the warning “Parking Brake Unavailable” may show up on the dashboard lock, and the car may not start.
- Powering the EPB: The parking brake system of EPB is powered by the car’s battery. If this is the case, it can cause an insufficient charge, and the system won’t function properly.
- Issues with Electrical Communication: Low battery voltage may interfere with communication between the Electronic Parking Brake (EPB) and other key systems, including the ignition system. The car may not start until this is resolved.
Symptoms of a Weak Battery: A weak or failing battery can cause many problems in your car, including with the electronic parking brake system. Problems caused by a weak battery can lead to more serious problems, including the “Parking Brake Unavailable” warning, which prevents the car from starting.
- Dashboard warning lights (including the “Parking Brake Unavailable” message).
- Ignition turns with no crank or start.
- Headlights are dim or flicker.
- Sound of clicking when trying to start the car.
What To Do: The “Parking Brake Unavailable” warning can be frustrating. When trying to troubleshoot and resolve the warning, you can take the battery or other components to some of the more complicated repairs.
- Test the Battery: The first step is testing the battery to see if it is still mounting the voltage needed. You can often get a battery test done for free at many auto parts stores.
- Replacing the Battery: If the battery is weak or old (usually over 3-5 years), it may need to be changed. A new battery should fix the problem and activate the EPB system again.
- Jump-Starting the Car: If the battery is not completely dead, you may be able to jump-start the car. A jump-start will temporarily fix the problem so you can get the engine to start.
2. Faulty EPB Module or Actuator
The EPB module controls the parking brake. If it fails or if the actuators (the small motors that apply the parking brake to the rear wheels) fail, it can cause the system to run the “Parking Brake Unavailable” message and prevent the car from starting. The EPB system has to use motors to engage and disengage the brake, so if one of the components fails, it can disrupt the system.
Causes of EPB Module or Actuator Failure
The actuators and the electronic parking brake module are what control the parking brake. When either of these components fail due to moisture, wear, or even electrical issues, you may get the “Parking Brake Unavailable” warning and not be able to start the car.
- Wear and Tear: Car parking brake components can experience some amount of basic wear and tear and fail to engage the brake correctly. This is especially true for older vehicles or vehicles that used the parking brakes frequently.
- Moisture or Contaminants: Moisture and other contaminants can damage and wear the parking brake systems too. The various components of parking brake systems, such as the module and actuators, can fail when surrounded by dirt, debris, and especially moisture.
- Electrical Short or Malfunction: An electrical short or other electrical malfunction can cause the parking brake system to malfunction.
Action Steps:
Examine the Fault Codes: A mechanic has the ability to use a special scan tool that detects fault codes. A fault code can lead to the repair of the parking brake system components, such as the module or the actuators.
Repair the Faulty Component: When the parking brake system components, such as the module or actuator, are found with no faults, replacement of the component is required. The replacement of components is a repair that may be beyond the skills of a vehicle owner.
3. Loose or Corroded Battery Terminals
Another common reason that could cause the “Parking Brake Unavailable” warning is corrosion at the battery terminals. As dirt and moisture build up over time, the battery terminals can accumulate corrosion that results in an insufficient electrical connection. Consequently, the EPB system may not receive the power it needs to work.
Additionally, the battery having loose connections can cause the voltage to be unstable and affect the parking brake system.
What to Do:
Examine the Battery Terminals: Find a wire scrub and prepare a corrosion cleaning solution. This can be done by mixing water and baking soda. After scrubbing, your battery terminals should be clean and the electrical connection should be improved.
Tighten Loose Connections: Inspect the battery terminals and ensure that the cables are tightly secured to the terminals. If they are not, use a wrench to tighten them.
Inspect for More Corrosion: Inspect the terminals and cables for signs of corrosion. If the corrosion is too much, the cables need to be replaced.
4. Issues with Sensors or Wiring
The Electronic Parking Brake (EPB) system uses several sensors to keep track of the status of the brakes. If one of the sensors stops working, the car will not be able to tell if the parking brake is on or off. This can cause the message, “Parking Brake Unavailable,” to appear on the dashboard.
Wiring that is damaged or worn can also cause problems with communication between the components of the EPB system. If a wire is broken, the parking brake will malfunction, and the car will not be able to start.
What to Do:
- Inspect the Wires: Look for visible damage that connects the wiring to the EPB system. Be sure to check the spots where the wires may have been worn down or broken.
- Replace Bad Sensors: Sensors are not repairable, so if one of them is broken, it will need to be replaced. It’s a good idea to bring the car to a mechanic to help figure out which one is broken.
- Check for Fault Codes: It’s best to have a professional address these specific issues once the problem with the sensors or wiring has been found. A diagnostic scan will determine which ones need to be replaced.
5. Software or Control Unit Glitch
As vehicles become more reliant on software, so too does the EPB system. A software issue with the parking brake control unit could cause a system malfunction that triggers the “Parking Brake Unavailable” alert. This could be a result of a recent software update, power surge, or a software bug.
What to Do:
- System Reset: You may be able to reset the EPB system. This sometimes helps to restore the system by correcting temporary software bugs.
- Software Update: At a dealership or service center, you should check if the parking brake system software needs to be updated (newer versions may be available). This could fix the problem.
How Electronic Parking Brakes Work
In place of the traditional mechanical handbrake, the electronic parking brake (EPB) is a more modern option. Instead of having to pull a lever to engage or disengage the parking brake, you just press a button. The EPB system is more dependable as it uses electric motors at the rear wheels to engage and disengage the brakes.
Most cars have a system that automatically engages the parking brake when the car turns off. When the car is turned on, the parking brake is released, and the car is free to drive. If there is something wrong with the parking brake system, the car may not start. This can happen due to things like low battery voltage, faulty wiring, or bad actuators. This is to keep you and your car safe from the parking brake system issues.
Step‑by‑Step First Checks Before Repairs
There could be a simple cause for a malfunction. Cars can be simple, and a click of a battery or some dirt on a cable can cause the system to malfunction. A DIY can save you money and time from a trip to the mechanic.
Step 1: Inspect the battery
Start investigating the malfunction of the parking brake system by checking the battery. If the battery is weak, it can cause the system to malfunction, and a warning to show on the dashboard.
- Take the car to an auto parts shop to have the battery tested for free. If it is low, get a new one.
- Jump-starting your vehicle can be a temporary solution to your parking brake problems if the battery is still weak and not completely dead.
- Jumping the car battery.
Step 2: Check the battery terminals and fuses.
If the fuses and battery aren’t the issue, then the terminals may have spotty connections, corrosion, or both. To make sure that they can provide adequate electrical flow, clean the terminals and make sure the connections are tightly secured.
Next, check to see if any fuses are blown in the box, especially the ones that are tied to the parking brake system, and replace any that are if they are the right ones.
Step 3: Reset the EPB System
In some cases, minor software problems can be solved with the simple resetting of the EPB System, and the parking brake can return to its normal working order.
Step 4: Get a Diagnostic Scan at the Mechanic
If no prior solutions have worked and the parking brake still isn’t functioning, a mechanic should be your next stop. He can read the fault codes with a special tool to pinpoint the problem and repair it.
Frequently Asked Questions
Here are some FAQs about parking brake unavailable car won’t start –
1. Why does my car say parking brake unavailable and won’t start?
In short, it is a malfunction in the electronic parking brake system, whereby the car’s engine won’t start as a safety precaution.
2. Can a weak battery cause this?
Yes! A weak or dead battery is the most common cause of “Parking Brake Unavailable” warning.
3. Will jump-starting the car fix it?
If your problem is caused by a weak battery, jump-starting the car may fix the warning temporarily.
4. Is this dangerous?
Yes, it is dangerous to drive when your car has an issue because it could become unsecured when parked. Avoid driving it until the problem is fixed.
5. Do I need a mechanic?
If the simple troubleshooting steps do not help, it is time to see a mechanic. They have the special tools needed to diagnose and repair the problem.
Conclusion
Getting the message “Parking Brake Unavailable: Car Won’t Start” can understandably be concerning. Usually, this issue can be traced back to the electronic parking brake system. There can be a variety of reasons why problems in the system arise including a weak battery, faulty parking brake system components, or a faulty parking brake sensor. With the troubleshooting implications we have provided for you, you may be able to track down the underlying problem before it gets worse.
