CDL Class B - Air Brakes 2025 LATEST
UPDATE
Air brakes use ____ to make the brakes work. - ANSWER Compressed air
The ____ brake system applies and releases the brakes when you use the brake pedal
during normal driving. - ANSWER Service
The _____ brake system applies and releases the parking brakes when you use the
parking brake control. - ANSWER Parking
The ______ brake system uses parts of the service and parking brake systems to stop
the vehicle in a brake system failure. - ANSWER Emergency
What does the air compressor do? - ANSWER The air compressor pumps air into the
storage tanks (reservoirs)
The air compressor is connected to the engine through ________. - ANSWER Gears or
a v-belt
There are different kinds of air compressors. How may the air compressor be cooled? -
ANSWER -Air cooled
-Engine cooling system
If the compressor has its own oil supply, what must you be sure to do? - ANSWER
Check the oil level before driving
What does the air compressor governor do? - ANSWER The governor controls when
the air compressor will pump air into the air storage tanks.
What do the air storage tanks do? - ANSWER Used to hold compressed air
When air tank pressure rises to the "cut-out" level, the governor stops the compressor
from pumping air. What level is the "cut-out" level? - ANSWER Around 125 pounds per
square inch (psi)
When the tank pressure falls to the "cut-in" pressure, the governor allows the
compressor to start pumping again. What is the "cut-in" level? - ANSWER Around 100
pounds per square in (psi)
True or false? The number and size of air tanks varies among vehicles. The tanks will
hold enough air to allow the brakes to be used several times even if the compressor
stops working. - ANSWER True
UPDATE
Air brakes use ____ to make the brakes work. - ANSWER Compressed air
The ____ brake system applies and releases the brakes when you use the brake pedal
during normal driving. - ANSWER Service
The _____ brake system applies and releases the parking brakes when you use the
parking brake control. - ANSWER Parking
The ______ brake system uses parts of the service and parking brake systems to stop
the vehicle in a brake system failure. - ANSWER Emergency
What does the air compressor do? - ANSWER The air compressor pumps air into the
storage tanks (reservoirs)
The air compressor is connected to the engine through ________. - ANSWER Gears or
a v-belt
There are different kinds of air compressors. How may the air compressor be cooled? -
ANSWER -Air cooled
-Engine cooling system
If the compressor has its own oil supply, what must you be sure to do? - ANSWER
Check the oil level before driving
What does the air compressor governor do? - ANSWER The governor controls when
the air compressor will pump air into the air storage tanks.
What do the air storage tanks do? - ANSWER Used to hold compressed air
When air tank pressure rises to the "cut-out" level, the governor stops the compressor
from pumping air. What level is the "cut-out" level? - ANSWER Around 125 pounds per
square inch (psi)
When the tank pressure falls to the "cut-in" pressure, the governor allows the
compressor to start pumping again. What is the "cut-in" level? - ANSWER Around 100
pounds per square in (psi)
True or false? The number and size of air tanks varies among vehicles. The tanks will
hold enough air to allow the brakes to be used several times even if the compressor
stops working. - ANSWER True
