What occurs if the air dryer fails in an air brake system?

Answer: B — Moisture can enter the system

When the air dryer in an air brake system fails, moisture can enter the system. The primary function of the air dryer is to remove moisture from the compressed air before it reaches the brake components. If the dryer is not functioning, this moisture can accumulate within the air system, leading to various issues such as the freezing of air lines, corrosion of brake components, and reduced braking effectiveness. Excess moisture not only compromises the brake system's reliability but can also create hazardous conditions, especially in colder climates where the moisture can freeze. This can lead to malfunctions of the brakes, making it essential to ensure that the air dryer is operational to maintain the integrity and safety of the air brake system.