Operation & SafetyQuestion 53 of 60
If your air brakes fail and pressure drops, what safety feature will eventually stop the vehicle?
a.The service brake pedal alone
b.The trailer hand valve
c.The spring (emergency/parking) brakes applying automatically
d.The alcohol evaporator
Explanation
If air pressure drops too low, the spring brakes apply automatically because there is no longer enough air to hold the springs back. This is designed to stop the vehicle when the air system fails. However, the driver should react early to a low-pressure warning rather than wait for automatic application.
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Related questions on this topic
- What is the proper braking technique (snub braking) on a long downgrade?
- On a vehicle with air brakes, when is the proper time to release the brakes during snub braking on a downgrade?
- Compared to a car, how does the stopping distance of a heavy vehicle with air brakes change as weight and speed increase?
- What should you do first if the low air pressure warning comes on while driving?
- When stopping normally with a vehicle equipped with air brakes, how should you apply the brakes?
- Why should you not fan (pump) the brakes on and off on a long downgrade with standard air brakes?
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