Brakes Locking Up: Why It Happens and How To Solve It

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Brakes locking up is a thing of the past, thanks to the invention of the anti-locking braking system. However, brakes do lock up occasionally, which can pose a danger to you, the vehicle and other road users.

Brakes Locking Up

Knowing what to do in such situations is crucial and can be the thin line between safety and an accident. In this article, we’ll discuss some reasons why brakes lock up and how to fix them to keep you and the vehicle safe.

What Causes Brakes Locking Up?

Factors that cause brakes locking up include mechanical problems, binding brake calipers, bad weather conditions, a faulty hydraulic system and a broken piston. Other reasons the brakes will lock are a faulty master cylinder, a defective brake booster, a malfunctioning ABS computer and a compromised speed sensor.

Sometimes a driver reacting wrongly to road conditions can cause the brakes to lock up. For example, when the wheels lock during driving, pumping the brakes on a vehicle fitted with ABS will confuse the computer. This can cause the brakes to lock up, increase the braking distance, and make steering difficult. Rather, hold your feet firmly on the brake pedal without pressing too hard.

Doing this should activate the ABS and bring the vehicle to a safe stop. However, if your car doesn’t have ABS, take your foot off the accelerator and put your gear in neutral. Allow the car to skid sideways while the tires gain traction. Immediately, you feel the traction return to your tires, steer the vehicle in the direction you want to go and gently accelerate.

  • When Brakes Develop Mechanical Problems

Brakes are mechanical devices that can develop faults like other car parts. These faults can impair the normal function of the brakes, causing them to lock even when the vehicle has ABS.

Causes of Brakes Locking Up

The issues don’t have to be grand; minor faults such as rust on rotors, damaged brake pads and axels that get hotter than the rest can result in brake locking. Also, the brake pedals could malfunction in normal driving conditions and lock up the brake system.

  • Seized Brake Calipers Can Cause Locking

The calipers help in slowing the car by creating friction with the brake pads and clamping the wheels’ rotors to stop the car. Seized calipers mean that the calipers are stuck to the brake pads and refusing to release.

There are numerous reasons why calipers can get stuck, including aging, rusting, stuck pistons, or stuck brake pads. Other simple factors, such as rust or wear and tear, can render caliper locked up after brake job.

  • Bad Weather Can Make the Tires Lose Traction

Heavy rain or snow can contribute to locking brakes by reducing the traction between the tires and the road. Tires depend on the traction between their threads and the road to stop the vehicle.

When the road is slippery after a downpour of snow, the tires are unable to grip the road properly due to the slick surface. Firmly depressing your brakes won’t work either, as the tires have stopped spinning and begun skidding.

This is where the ABS kicks in. A sensor sends a signal to the system indicating the wheel that is stuck. The system then reduces power to that wheel and transfers more power to wheels with more traction. This puts the driver back in control of the vehicle, and he can steer it out of danger.

  • A Faulty Hydraulic System

The hydraulic system creates hydraulic pressure when the pedal is depressed. This pressure forces the brake pads against the wheels and stops the vehicle. The essence of the hydraulic system is to reduce the amount of force applied to the pedals to slow down the car. However, a faulty hydraulic system may cause excess pressure on the brake pads and refuse to release the pads, resulting in a brake lock.

Factors that affect a hydraulic system include contaminated or inadequate fluid. Using the wrong fluid can also affect the function of the system. When a brake caliper is saturated with fluid because of a leak, it can also cause a brake lock.

During hard braking, a bad brake system proportional valve may deliver equal hydraulic pressure to the brakes. Thus, causing wheel lock on the rear wheels in the process. A faulty ABS pump can lead to a brake lock-up due to contaminated fluid. This faulty ABS may cause braking problems, including brake locking up.

  • A Malfunctioning Caliper Piston Stuck to the Pads

When the caliper piston (or the vehicle) hasn’t been in use for a while, it becomes sensitive to heat and refuses to retreat. The brake caliper piston pushes the brake pads onto the wheels to stop the vehicle and then retreat to allow the vehicle to move again. It’s normal for the caliper pistons to get hot, but a heat-sensitive piston will get stuck after pressing the brake pads. This leads to brake-locking as the wheels can’t spin anymore.

Stuck caliper pistons are caused by rust, dirt, and inactivity. Thus, you need to service the braking system regularly to ensure all the parts are in prime condition.

  • A Broken Master Cylinder

The master cylinder distributes hydraulic pressure throughout the braking system according to the pressure applied on the pedal. If the master cylinder becomes faulty, it won’t distribute the hydraulic pressure equally, thus sending more pressure to one side while the other side receives less.

For example, a brake caliper may get stuck if it receives more hydraulic pressure and if the liquid refuses to retreat after serving its purpose. A broken master cylinder can also cause a mushy pedal, resulting from air in the brake lines. A mushy pedal will sink to the floor when you depress it, making the braking system lose its power.

  • A Malfunctioning Brake Booster

A brake booster increases the hydraulic pressure produced by the master cylinder. It amplifies the force of the pedal in stopping the car. That is why you don’t have to press hard on the brakes for them to work. The booster’s work ends after lifting your leg off the pedal. However, a malfunctioning booster will continue to amplify the hydraulic pressure even when your leg is off the pedal. This will force the brakes to lock, increasing the braking distance.

  • A Compromised ABS Computer

A compromised ABS computer might do what the ABS was invented to fight: locked brakes. As we explained earlier, the ABS prevents locking by increasing the braking power when it senses wheel lock. The ABS is controlled by the ABS computer, which interprets data from the wheel sensors and uses it to activate the anti-locking feature.

However, if the ABS computer is compromised, it might send the wrong signals to the anti-locking feature, which will lock the brakes. A faulty ABS system will illuminate its corresponding light on the dashboard to draw your attention.

How To Fix Brakes Locking Up

To fix brakes locking up, you’ll need to diagnose the exact cause of the problem. For instance, a faulty master cylinder, brake booster, and caliper pistons need replacing. When your tires easily lose traction, it may be time for a new set of tires.

  • Fixing a Compromised Master Cylinder

First, you’ll need to find the master cylinder, which is situated under the brake fluid reservoir. Next, draw out the fluid from the cylinder with a turkey baster and disconnect the fluid sensor connector. Unscrew the fluid lines with a wrench and remove the master cylinder. Screw the new cylinder into place and fill the reservoir to the brim, allowing some liquid to spill over into the brake pipe holes.

Allow an assistant to pump the brakes while placing a drain pan under the holes to catch the fluid. Attach the brake lines and reconnect the fluid sensor. Pour the new fluid into the reservoir and bleed the new master cylinder with a bleeder kit.

  • Fixing a Faulty Brake Booster in a Few Steps

Find the brake booster, which is usually found behind the master cylinder’s firewall. Next, remove the clamps/fasteners that hold it in place and separate it from the master cylinder.

Fix Brakes Locking in Car

Also, unscrew all the bolts restraining the pedal to access the booster. Then install the new brake booster and return all the bolts and fasteners you removed earlier.

  • How To Repair a Compromised ABS Computer

Fixing a faulty ABS is quite a complicated process and can only be done by experts. The process involves repairing the ABS power loss and checking the signals from the wheel sensors. The most important thing is finding a reputable mechanic to get to the bottom of the issue and do an excellent repair job. You can also visit your car dealership to find out if they can help out.

  • Repairing a Faulty Hydraulic System

Repairing a faulty hydraulic system depends on the exact cause of the problem. For instance, cracked hoses need replacement, while broken seals can be fixed with a stop leak. Ensure you top up the fluid if it’s not enough and bleed the brakes if you use the wrong fluid. We recommend you contact a certified mechanic to help you diagnose the problems and proffer a solution.

Frequently Asked Questions

– What Are the Signs of Sticky Brakes?

The signs of sticky brakes are the car moving to one side, being sluggish, hot wheels, grinding noises, burnt smell, brake pedal sinking to the floor and leaking brake fluid. Also, difficulty in stopping your vehicle or hearing high-pitched noises during braking are signs that your brakes need repair.

– How Do You Release Your Parking Brake When Stuck?

You release your parking brake when stuck by getting under it and manually trying to pull on the brake cables. You can set and release the cable many times to ensure the brakes are released. Also, try activating the e-brake by pulling the foot lever higher than the foot pedal.

Seized Brake Calipers

Conclusion

This article has discussed the various factors that make brakes lock up during driving and has suggested solutions to them.

Here is a summary of all the major takeaways:

  • A faulty master cylinder, brake booster, piston caliper, ABS computer and caliper are some of the reasons why brakes will lock up.
  • Sometimes bad weather, wrong driver reactions to conditions on the road and a faulty hydraulic system can make the brakes malfunction and get stuck.
  • The best way to solve this problem is by replacing the damaged parts such as the master cylinder, brake booster, calipers and pistons.
  • However, if you’re driving and the brakes get stuck, remove your legs from the accelerator, shift the gear into neutral and allow the vehicle to gain traction before steering it.
  • Remember to bleed the brakes to eliminate air bubbles and other contaminants whenever you install a new braking system component.

If you have a compromised ABS computer, you can visit your car dealership to see if they can help you fix it. Don’t try to fix it on your own, as you might end up worsening the problem.

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Ran When Parked
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