There's nothing scarier than realizing your brakes aren't functioning as they should while on the road. Issues can range from very mild to serious, so it's always best to check them on a regular basis. If you happen to find an issue while driving or during your daily checks, this handy symptom sheet will help you better determine what's causing the issue.
Pedal Goes Right to the Floor With No Pressure
This is quite common in total brake failures. Without question, you should never drive in a vehicle that does this.
The most common cause for issue lies in the master cylinder. It can also mean your hydraulic system is faulty. There's often a bit of variation with this type of issue, so you can experience mostly normal brake function with just occasional issues, or an issue that prevents use altogether.
In general, if you take your foot off of the pedal and it sinks, you have a problem that needs to be addressed by a specialist.
Pedal Feels "Marshmallowy" When Pressed
Often, vehicles are brought into brake specialty centers with the complaint that the pedal feels "spongy" or "marshmallowy." The pedal itself can still be pressed but goes down much more quickly with less resistance.
This is usually due to excess air in the system. You may need to bleed off some of this air if you know how. This should be done a little at a time until the right resistance is found.
If you still experience sponging, double-check your brake fluid to ensure you have enough. Low brake fluid also has this symptom.
Loud Squealing or Squelching When You Press the Pedal
The sound of two metal parts rubbing together isn't just bad, it's almost as bone-chilling as nails on a chalkboard. Above all other issues, this is likely one of the most common that brings vehicle owners into the shop.
In a vast majority of cases, it happens because the brake pads themselves have simply met their match time-wise. Your brakes will often still function close to normal, but you should not drive unless you absolutely have to — total brake failure is possible in this situation, and may happen very suddenly.
There's an easy way to prevent this from happening. Change your brake pads out regularly, especially if you do a fair amount of traveling on a daily basis. Most have a wear indicator to help you tell when they're too worn to be effective.
Brake Pedal is Locked Into Place
The exact opposite of a spongy brake problem, brake pedals that don't move at all are another common symptom. Some mechanics refer to this as a "hard brake pedal" or "jammed pedal." It can happen in the middle of driving, but is much more common in vehicles that aren't frequently driven.
For obvious reasons, this type of issue means you must call a tow truck. Never drive with a locked pedal, even if you are confident you can drive slowly on backroads or side streets. Accidents can still happen — while you may be predictable, other people, animals and objects may not.
When the brake pedal jams, it can be complex to source the issue. It may be caused by:
- A defective brake booster check valve
- Lack of vacuum (required to provide pedal action)
- Your vehicle is extremely cold and simply isn't recognizing turnover
- You either have too much air or too little air in the system
- The caliper has seized
- There's a leak in your air brake line somewhere
This isn't necessarily easy to identify, either, without opening the hood and/or putting the vehicle up on blocks. There are a few tricks you can try before calling a tow truck, thankfully.
Depress the Brake While Starting
Firstly, try to depress the brake any small amount you can shortly before starting the car — often, you'll get 1/8-inch to 1/4-inch worth of depression if you press really hard. Sometimes, your vehicle sensors can become a bit wonky, especially if your car is designed to turn off the brake pedal when parked. This may be enough to clear the issue through.
Check the Vacuum Hose
If that doesn't work, it's time to think back a bit. If you've been working on your car recently, lift the hood and ensure the vacuum hose and brake fluid cap are all in place correctly. If the vacuum hose is backward, it won't provide suction — leading to no brakes.
If these both fail and your vehicle is sufficiently warm, try adding or removing a bit of air to the line. If that still fails, it's time to call in the professionals.
Your brakes keep you and everyone else around you safe, so it's important they are regularly maintained. If you even just suspect there is an issue somewhere in the system, it's crucial you pull your vehicle off the road and locate the problem. For questions about these symptoms or any other brake problem, call your local mechanic for assistance and to learn more.