Air Brake Test Basic 2 — Questions and Answers
Question 1: In an air brake system, what component stores the compressed air for use by the brakes?
- Air reservoir tanks (Correct answer)
- The governor
- The slack adjuster
- The brake chamber
Correct answer: Air reservoir tanks
Air reservoir tanks hold the compressed air that operates the brakes.
Question 2: What does the air compressor governor control?
- When the compressor pumps air into the reservoirs (Correct answer)
- The speed of the truck
- The brake pedal pressure
- The parking brake force
Correct answer: When the compressor pumps air into the reservoirs
The governor controls when the compressor cuts in and out to maintain reservoir pressure.
Question 3: At what pressure does the low air pressure warning typically activate?
- Below 60 psi (Correct answer)
- Below 100 psi
- Below 120 psi
- Below 150 psi
Correct answer: Below 60 psi
The low air pressure warning must activate before pressure drops below 60 psi.
Question 4: What is the purpose of draining the air tanks daily?
- To remove water and oil that collect in the tanks (Correct answer)
- To increase air pressure
- To clean the brake pads
- To test the warning light
Correct answer: To remove water and oil that collect in the tanks
Draining removes accumulated water and compressor oil that can damage the system.
Question 5: What device automatically expels moisture and removes oil from the air system?
- Air dryer (Correct answer)
- Slack adjuster
- Foot valve
- Relay valve
Correct answer: Air dryer
The air dryer collects and removes moisture and oil before air enters the reservoirs.
Question 6: Normal operating air pressure for a heavy vehicle is generally in what range?
- 100 to 125 psi (Correct answer)
- 40 to 60 psi
- 150 to 200 psi
- 20 to 40 psi
Correct answer: 100 to 125 psi
Most air brake systems operate between roughly 100 and 125 psi.
Question 7: What component converts air pressure into mechanical force to apply the brakes?
- Brake chamber (Correct answer)
- Air compressor
- Governor
- Air reservoir
Correct answer: Brake chamber
The brake chamber uses air pressure to push a rod that applies the brakes.
Air Brake Test Basic 2
In an air brake system, what component stores the compressed air for use by the brakes?