CDL · Air brakes
Air escaping from the safety relief valve of an air brake system is a sign that:
Correct answer: something in the system is wrong.
Answer options
- Athe system is working normally
- Bthe brakes are getting extra power
- Csomething in the system is wrong Correct
Why
The safety relief valve protects the first air tank by opening only when pressure climbs too high, usually around 150 psi. If it is venting air, part of the system is not working right, and a mechanic should repair it.
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
- What is the purpose of the alcohol evaporator found on some air brake systems?
- Which of the following correctly describes air brakes?
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- What is true of slack adjusters in an air brake system?
- In an air brake system, what is the compressor governor responsible for?
- When a vehicle has air brakes, what is the brake pedal's job?
- In an air brake system, which statement about the storage tanks is true?
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