Brake lock-up is a situation where the brakes on a vehicle engage on their own or lock up when you need them most, which can be both dangerous and nerve-wracking. There are several reasons why brakes can lock up, including:

• Overheated braking system: This can happen when you brake hard to avoid an accident or when you brake gently to glide to a stop. Essentially, the force of applying the brakes (even lightly) can activate the full stopping power of your brakes, bringing you to an abrupt and less-than-safe stop.

• Using the wrong brake fluid: Using the wrong brake fluid, having excessive brake fluid in the master cylinder, unchanged old fluid, or a faulty brake valve can all lead to brake drag.

• Damaged or broken parts: Damaged or broken parts such as calipers, brake pads, pistons, rotors, or others can cause brake lock-up.

• Defective ABS components: Defective ABS components can cause the brakes to lock up.

• Broken parking brake: A broken parking brake can cause the brakes to lock up.

• Sticking brake caliper or wheel cylinder: A sticking brake caliper or wheel cylinder can cause the brakes to lock up.

• Corrosion: Corrosion can cause the brakes to lock up.

• Non-functioning ABS unit: A non-functioning ABS unit can cause the brakes to lock up.

• Worn tires: Worn tires can cause the brakes to lock up.

When brakes lock up, quick action could help you. If you experience brake lock-up, you should:

• Stay calm: Try to stay calm and avoid panicking.

• Pump the brakes: Pump the brakes gently to try to release them.

• Shift into neutral: Shift into neutral to help slow the vehicle down.

• Steer to safety: Steer the vehicle to a safe location, such as the side of the road.

• Get help: Call for help or have the vehicle towed to a mechanic for repair.

It is important to have your brakes checked regularly to prevent brake lock-up and ensure your safety on the road.