When the spring brakes are on, which action is appropriate?

When the spring brakes are on, which action is appropriate?

• A. Never press the brake pedal
• B. Press the brake pedal gently to test
• C. Use engine braking only
• D. Use parking brake only

Answer: (A)

When the spring brakes are on, the parking brakes are engaged by springs and hold the wheels in place. Pressing the brake pedal in this situation won’t provide proper braking and can release the parking brakes, allowing the vehicle to move unexpectedly. That’s why the appropriate action is to avoid using the foot brake while the spring brakes are on. In other words, wait until the parking brakes are released and the air system is charged before relying on the service brakes. The other options either attempt to test or rely on brakes that aren’t effective or safe in this condition.

When the spring brakes are on, the parking brakes are engaged by springs and hold the wheels in place. Pressing the brake pedal in this situation won’t provide proper braking and can release the parking brakes, allowing the vehicle to move unexpectedly. That’s why the appropriate action is to avoid using the foot brake while the spring brakes are on. In other words, wait until the parking brakes are released and the air system is charged before relying on the service brakes. The other options either attempt to test or rely on brakes that aren’t effective or safe in this condition.