Basic Flashcards
7 cards from real Air Brake Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Basic flashcards as text
What is the purpose of the slack adjuster in an air brake system?
Answer: To adjust the brake shoe clearance as linings wear
The slack adjuster keeps the brakes properly adjusted as the linings wear down.
When parking a vehicle with air brakes, what should you do?
Answer: Apply the parking (spring) brakes
Always set the parking brakes; never rely on holding the service brake pedal.
What does a dual air brake system provide?
Answer: Two separate air systems for added safety
A dual system has two independent circuits so braking remains if one fails.
During a static air leakage test with the engine off and brakes released, how much pressure loss per minute is acceptable for a single vehicle?
Answer: Not more than 2 psi
Leakage should not exceed 2 psi per minute for a single vehicle with brakes released.
What should you do if the low air pressure warning comes on while driving?
Answer: Stop safely as soon as possible and park
Bring the vehicle to a safe stop immediately because brake failure may be imminent.
What controls the parking and emergency brakes in most heavy vehicles?
Answer: A separate dashboard control valve
A dash-mounted control valve operates the spring-applied parking and emergency brakes.
Why must you not use the spring (parking) brakes if the regular brakes are overheated?
Answer: Heat can damage them or they may not hold once cooled
Applying spring brakes to hot drums can damage them and they may not hold as the brakes cool and contract.