What is the appropriate action if your brakes fail while driving?

When brakes fail while driving, the most effective course of action is to shift to a lower gear and use the parking brake if necessary. This method allows the driver to gradually reduce the speed of the vehicle without causing a sudden stop, which could lead to loss of control. Shifting to a lower gear effectively utilizes the engine's resistance to help slow down the car. Using the parking brake can further assist in stopping the vehicle, but it should be applied cautiously to avoid locking up the rear wheels, which could result in skidding.

Choosing this option ensures that the driver maintains better control of the vehicle during a critical and potentially dangerous situation, guiding it to a stop safely. It's also important to execute this action in a way that does not compromise the vehicle's stability, which is why simply relying on the emergency brake or emergency actions without shifting gears may not be as effective or safe. This approach provides a more comprehensive and controlled method of handling brake failure.