The purpose of warning lights and buzzer in the air brake system is to notify the operator of low air pressure.

• A. True
• B. False
• C. Not specified
• D. Only when parking brakes apply

Answer: (A)

Warning systems in air brake setups alert the driver to low air pressure. This is essential because air brakes rely on stored compressed air to function correctly, and if the pressure drops too low, braking effectiveness can be reduced and brakes may even release unexpectedly. The warning light and buzzer provide an immediate, attention-grabbing signal so the operator can stop safely, recharge the system, and prevent brake failure. These warnings are about low air pressure in general, not limited to parking brakes, so the statement is true.