CDL · Air brakes
Your air brake system's safety relief valve starts letting air escape. What does this tell you?
Correct answer: Something in the system is not working right.
Answer options
- ASomething in the system is not working right Correct
- BEverything is normal and no action is needed
- CThe brakes are getting extra stopping power
Why
This valve guards the tanks against excess pressure and is usually set to open at about 150 psi. If it releases air, pressure is climbing higher than it should, which points to a fault that a mechanic needs to fix.
About this question
Topic: Air brakes License: CDL
Part of these practice sets:
Where it applies: Asked in every state.
Practice the whole set
This question is part of How Air Brakes Work (18 questions). Take the full set and check your score.
Practice How Air Brakes WorkMore questions from How Air Brakes Work
- In an air brake system, which statement about the storage tanks is true?
- Air-braked trucks and buses most often use which kind of brake at the wheels?
- In an air brake system, what is the compressor governor responsible for?
- On an air brake system, what pressure does it normally take for the safety valve to open?
- Besides the service brake and the parking brake, what is the third braking system that makes up air brakes?
- In an air brake system, what is the purpose of the air storage tanks?
- Which of the following correctly describes air brakes?
- If the air compressor springs a leak, which valve keeps the stored air from escaping?
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