CDL CLASS A AIR BRAKES TEST
QUESTIONS & ANSWERS
All vehicles with air brakes are required to have a low pressure warning signal. This
could be...
A) a red light
B) a wig wag mechanical arm
C) a buzzer
D) any of the above - ANSWER D
To test the low pressure warning signal, you should do all BUT the following...
A) shut the engine off
B) turn the electrical power on
C) ask a friend to listen for the signal
D) step on and off the brake pedal to reduce air pressure - ANSWER C
If your truck or bus has dual parking control valves it means that you can use pressure
from a separate tank to:
A) balance the service brake system
B) release the spring brakes to move a short distance
C) stay parked without using up service air pressure
D) apply more brake pressure if the main tank is getting low - ANSWER B
When the low pressure warning is activated, you should...
A) wait for the air brakes to come on automatically
B) bring the vehicle to a safe stop while you still control the brakes
C) monitor your air pressure gauge and maintain highway speeds
D) pump the brake pedal hard to stop - ANSWER B
Your truck or bus has a dual air brake system. If a low air pressure warning comes on
for only one system, what should you do?
A) reduce your speed and drive to the nearest garage for repairs
B) continue at normal speed and find a garbage before the brakes lock
C) reduce your speed and test the remaining system while under way
D) stop. safely park, and continue only after the system is fixed - ANSWER D
To test your service brakes you should...
A) stop the vehicle and put the parking brake on
B) release the parking brake, move forward slowly and depress brakes
C) put parking brake on and release air pressure
D) depress brakes when traveling at highway speeds - ANSWER B
Stab braking occurs when you...
A) press on the brake pedal as hard as you can
, B) release the brakes when the wheels lock up
C) apply the brakes when the wheels start rolling
D) all of the above - ANSWER D
You should know that your brakes are fading when:
A) pressure on the brake pedal is released and speed increases
B) you have to push harder on the brake pedal to control your speed on a downgrade
C) the brake feels spongy when pressure is applied
D) less pressure is needed on the brake pedal for each stop - ANSWER B
Air brake equipped vehicles must have:
A) a supply pressure gauge
B) an air use gauge
C) at least two brake heaters
D) a backup hydraulic system - ANSWER A
The brake pedal in an air brake system:
A) is to be used as a footrest during normal driving
B) controls the speed of the air compressor
C) controls the air pressure applied to put on the brakes
D) is connected to slack adjusters by a series of rods and linkages - ANSWER C
The proper way to go down long grades is to...
A) use a low gear and push hard on the brakes
B) let up on the brakes from time to time to cool them
C) use a low gear and apply light pressure on the brakes
D) brake on and off down the hill - ANSWER C
The governor stops pumping air when it reaches the "cut out" level, or around...
A) 125 psi
B) 200 psi
C) 225 psi
D) 175 psi - ANSWER A
Compressed air is stored...
A) in the hoses
B) in the engine compartment
C) in the fuel tank
D) in the storage tank - ANSWER D
In a single vehicle with a fully charged air system, air pressure loss (after an initial drop)
should be less than...
A) 2 psi per minute
B) 3 psi per minute
C) 4 psi per minute
QUESTIONS & ANSWERS
All vehicles with air brakes are required to have a low pressure warning signal. This
could be...
A) a red light
B) a wig wag mechanical arm
C) a buzzer
D) any of the above - ANSWER D
To test the low pressure warning signal, you should do all BUT the following...
A) shut the engine off
B) turn the electrical power on
C) ask a friend to listen for the signal
D) step on and off the brake pedal to reduce air pressure - ANSWER C
If your truck or bus has dual parking control valves it means that you can use pressure
from a separate tank to:
A) balance the service brake system
B) release the spring brakes to move a short distance
C) stay parked without using up service air pressure
D) apply more brake pressure if the main tank is getting low - ANSWER B
When the low pressure warning is activated, you should...
A) wait for the air brakes to come on automatically
B) bring the vehicle to a safe stop while you still control the brakes
C) monitor your air pressure gauge and maintain highway speeds
D) pump the brake pedal hard to stop - ANSWER B
Your truck or bus has a dual air brake system. If a low air pressure warning comes on
for only one system, what should you do?
A) reduce your speed and drive to the nearest garage for repairs
B) continue at normal speed and find a garbage before the brakes lock
C) reduce your speed and test the remaining system while under way
D) stop. safely park, and continue only after the system is fixed - ANSWER D
To test your service brakes you should...
A) stop the vehicle and put the parking brake on
B) release the parking brake, move forward slowly and depress brakes
C) put parking brake on and release air pressure
D) depress brakes when traveling at highway speeds - ANSWER B
Stab braking occurs when you...
A) press on the brake pedal as hard as you can
, B) release the brakes when the wheels lock up
C) apply the brakes when the wheels start rolling
D) all of the above - ANSWER D
You should know that your brakes are fading when:
A) pressure on the brake pedal is released and speed increases
B) you have to push harder on the brake pedal to control your speed on a downgrade
C) the brake feels spongy when pressure is applied
D) less pressure is needed on the brake pedal for each stop - ANSWER B
Air brake equipped vehicles must have:
A) a supply pressure gauge
B) an air use gauge
C) at least two brake heaters
D) a backup hydraulic system - ANSWER A
The brake pedal in an air brake system:
A) is to be used as a footrest during normal driving
B) controls the speed of the air compressor
C) controls the air pressure applied to put on the brakes
D) is connected to slack adjusters by a series of rods and linkages - ANSWER C
The proper way to go down long grades is to...
A) use a low gear and push hard on the brakes
B) let up on the brakes from time to time to cool them
C) use a low gear and apply light pressure on the brakes
D) brake on and off down the hill - ANSWER C
The governor stops pumping air when it reaches the "cut out" level, or around...
A) 125 psi
B) 200 psi
C) 225 psi
D) 175 psi - ANSWER A
Compressed air is stored...
A) in the hoses
B) in the engine compartment
C) in the fuel tank
D) in the storage tank - ANSWER D
In a single vehicle with a fully charged air system, air pressure loss (after an initial drop)
should be less than...
A) 2 psi per minute
B) 3 psi per minute
C) 4 psi per minute
