E
.
Learndmv
DMV PRACTICE
Toggle navigation
Find your state
Exam types
Practice tests
Sign in
Create account
↗
← Leave quiz
Saskatchewan Air Brake Practice Questions - Saskatchewan Air Brake (Endorsement A) Exam
Practice mode
Question
1
of 25
QUESTION 1 / 25
What is the primary purpose of the air compressor in an air brake system?
Choose one answer below.
A
To cool the brake drums during heavy braking
✓
B
To pump air into the reservoirs to build system pressure
✓
C
To release the spring parking brakes directly
✓
D
To control the amount of force applied to the brake pedal
✓
QUESTION 2 / 25
According to the SGI Air Brake Manual, how far below the cut-out pressure does the governor normally let reservoir pressure fall before it cuts the compressor back in?
Choose one answer below.
A
About 5 to 10 psi (34 to 69 kPa)
✓
B
About 20 to 25 psi (138 to 172 kPa)
✓
C
About 40 to 50 psi (276 to 345 kPa)
✓
D
About 60 to 70 psi (414 to 483 kPa)
✓
QUESTION 3 / 25
What is the purpose of the safety valve on the supply reservoir?
Choose one answer below.
A
To release pressure if the governor fails and pressure exceeds 150 psi
✓
B
To allow the driver to manually release the parking brakes
✓
C
To prevent moisture from entering the service tanks
✓
D
To warn the driver of low air pressure in the system
✓
QUESTION 4 / 25
What colour is the trailer supply line (emergency line) gladhand coupling?
Choose one answer below.
A
Blue
✓
B
Yellow
✓
C
Red
✓
D
Green
✓
QUESTION 5 / 25
What colour is the trailer service line gladhand coupling?
Choose one answer below.
A
Red
✓
B
Blue
✓
C
Yellow
✓
D
Black
✓
QUESTION 6 / 25
What device alerts the driver if the system air pressure falls below 60 psi (414 kPa)?
Choose one answer below.
A
A loud safety pop-off valve on the reservoir
✓
B
A red trailer supply valve popping out from the dashboard
✓
C
A low-pressure warning device (light and buzzer)
✓
D
An engine automatic shutdown indicator
✓
QUESTION 7 / 25
How should moisture and oil be removed from the air reservoirs?
Choose one answer below.
A
By adding alcohol to the tanks daily
✓
B
By running the engine at fast idle for 10 minutes
✓
C
By opening the drain valves on all reservoirs daily
✓
D
By replacing the compressor air filter weekly
✓
QUESTION 8 / 25
What does the yellow diamond-shaped knob on the dash control?
Choose one answer below.
A
The tractor parking brakes
✓
B
The trailer supply valve
✓
C
The windshield wipers
✓
D
The engine governor override
✓
QUESTION 9 / 25
What does the red octagonal-shaped knob on the dash control?
Choose one answer below.
A
The vehicle's hazard lights
✓
B
The tractor's front axle brakes only
✓
C
The trailer supply valve (charges the trailer lines)
✓
D
The service brake application pressure
✓
QUESTION 10 / 25
What is the purpose of gladhands in a tractor-trailer combination?
Choose one answer below.
A
To secure the trailer cargo doors
✓
B
To connect the electrical wiring between tractor and trailer
✓
C
To connect the tractor and trailer air brake lines
✓
D
To adjust the slack of the trailer brakes automatically
✓
QUESTION 11 / 25
What is the normal governor cut-out pressure range for most air brake systems?
Choose one answer below.
A
60 to 80 psi (414 to 552 kPa)
✓
B
120 to 145 psi (828 to 1,000 kPa)
✓
C
150 to 180 psi (1,034 to 1,241 kPa)
✓
D
85 to 100 psi (586 to 690 kPa)
✓
QUESTION 12 / 25
What is the minimum air pressure required before driving a vehicle equipped with air brakes?
Choose one answer below.
A
60 psi (414 kPa)
✓
B
100 psi (690 kPa)
✓
C
120 psi (828 kPa)
✓
D
150 psi (1,035 kPa)
✓
QUESTION 13 / 25
What is the primary function of the treadle valve (foot valve)?
Choose one answer below.
A
To park the vehicle mechanically using cable tension
✓
B
To regulate the compressor output directly from the cab
✓
C
To control the flow of air pressure to the service brakes
✓
D
To automatically adjust the pushrod stroke length
✓
QUESTION 14 / 25
What mechanical force applies the parking/emergency brakes in an air brake system?
Choose one answer below.
A
High air pressure acting on the back of the brake chamber
✓
B
A strong steel spring located inside the brake chamber
✓
C
A hydraulic cylinder backup system in the differential housing
✓
D
An electric solenoid acting on the slack adjuster arm
✓
QUESTION 15 / 25
What is the purpose of chocking the wheels when testing air brakes?
Choose one answer below.
A
To prevent the air compressor from running during tests
✓
B
To prevent the vehicle from rolling when parking brakes are released
✓
C
To increase the speed of the air pressure build-up
✓
D
To lock the manual slack adjusters in place for measurement
✓
QUESTION 16 / 25
What is the function of the supply reservoir (wet tank)?
Choose one answer below.
A
To distribute air directly to the front wheel brakes only
✓
B
To house the low-pressure warning light switch
✓
C
To collect water and oil condensed from the hot air
✓
D
To provide auxiliary air to the cabin heater
✓
QUESTION 17 / 25
What is the first tank that receives compressed air from the compressor?
Choose one answer below.
A
The primary service reservoir
✓
B
The supply reservoir (wet tank)
✓
C
The secondary service reservoir
✓
D
The trailer emergency reservoir
✓
QUESTION 18 / 25
What is the function of a one-way check valve between reservoirs?
Choose one answer below.
A
To prevent air from flowing back to the supply source if it leaks
✓
B
To allow the driver to bypass the governor cut-out
✓
C
To balance pressures between the front and rear brakes during application
✓
D
To automatically apply the trailer spring brakes
✓
QUESTION 19 / 25
What does the trailer hand control valve (trolley valve) operate?
Choose one answer below.
A
The tractor parking brakes only
✓
B
The trailer service brakes independently of the tractor
✓
C
The automatic engine retarder (Jake brake)
✓
D
The fifth-wheel slide lock cylinder
✓
QUESTION 20 / 25
What happens to the spring brakes when the driver pulls out the parking brake control valve?
Choose one answer below.
A
High air pressure is sent into the chambers to apply the brakes
✓
B
The caging bolts are automatically unscrewed
✓
C
Air pressure is exhausted from the chambers, letting the springs apply the brakes
✓
D
An electrical signal locks the mechanical slack adjusters
✓
QUESTION 21 / 25
What holds the spring brakes in the released position?
Choose one answer below.
A
Heavy mechanical springs
✓
B
Air pressure inside the spring chamber
✓
C
The tractor parking brake dash valve
✓
D
A locking pin on the slack adjuster
✓
QUESTION 22 / 25
What is the purpose of the air dryer in an air brake system?
Choose one answer below.
A
To cool the compressor oil
✓
B
To warm up the air lines in sub-zero temperatures
✓
C
To filter out water and oil vapor before it enters the reservoirs
✓
D
To dry the brake linings after driving through water
✓
QUESTION 23 / 25
What is the primary purpose of slack adjusters?
Choose one answer below.
A
To adjust the tension of the engine compressor belt
✓
B
To regulate the compressor cut-in and cut-out pressures
✓
C
To adjust the distance (free play) between the brake linings and the brake drums
✓
D
To control the amount of lubrication sent to the brake chambers
✓
QUESTION 24 / 25
How should you check the operation of the low-pressure warning device?
Choose one answer below.
A
Run the engine at fast idle and check if the pressure gauge needle moves
✓
B
Turn the ignition key on, fan the brakes to drop pressure below 60 psi, and verify that the light and buzzer activate
✓
C
Disconnect the red trailer supply line while the engine is running
✓
D
Apply the foot brake fully and hold it for one minute while watching for pressure drops
✓
QUESTION 25 / 25
What is the main danger of water freezing in the air brake lines?
Choose one answer below.
A
It can dilute the brake fluid and reduce braking force
✓
B
It can block the air lines and prevent the brakes from applying or releasing
✓
C
It can cause the air compressor to run continuously at fast idle
✓
D
It can crack the brake drums and rotors due to thermal shock
✓
← Previous
0 of 25 answered
Next question →
Finish & see results →