What should you do if your brakes fail while driving?

If your brakes fail while driving, shifting to a lower gear and using the emergency brake is the most effective and safest action to take. By downshifting, you can utilize the engine's braking power to help slow down the vehicle. This technique reduces your speed and allows for better control over the vehicle as you come to a stop.

Using the emergency brake simultaneously can reinforce this slowing effect. The emergency brake is designed to be used in situations exactly like this, where traditional braking may not be functioning properly. Engaging the emergency brake gradually is important to avoid locking the wheels, which could cause a skid.

The other options present less effective alternatives. Accelerating increases speed, which is dangerous in this situation. Steering towards a barrier can result in injury and vehicle damage, and turning off the engine can lead to loss of steering control, making the situation more perilous. Hence, the recommended action emphasizes control and safety, aiming to stop the vehicle as smoothly as possible.