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The warning system turns on when the air pressure inside the service air tank decreases below?

  1. 80 psi.

  2. 60 psi.

  3. 50 psi.

  4. 40 psi.

The correct answer is: 60 psi.

The air brake warning system is designed to alert the driver when the air pressure in the service air tank drops to a level where safe operation is compromised. When the air pressure falls below 60 psi, the warning light or buzzer activates, signaling the operator to take immediate action. This threshold serves as a critical safety feature to prevent brake failure due to insufficient air pressure, which can lead to serious accidents. Maintaining air pressure above this level ensures that there is adequate force available for effective braking. If the pressure drops below this threshold, it indicates that the braking system may not function properly, thereby posing a risk during operation. Utilizing this warning system allows drivers to address potential issues proactively and maintain the safety and efficiency of their vehicle.