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Illinois CDL Air Brakes Test 2
Practice mode
Question
1
of 25
QUESTION 1 / 25
A dual air brake system:
Choose one answer below.
A
Has a single air brake system, but uses two sets of controls.
✓
B
Has one air brake system for each side of the truck.
✓
C
Has two brakes for each wheel.
✓
D
Has two separate air brake systems, but uses a single set of controls.
✓
QUESTION 2 / 25
On a truck with air brakes, the braking system’s air compressor:
Choose one answer below.
A
Pumps air into the air storage tanks.
✓
B
Fills the tires.
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C
Moves air to the back of the truck.
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D
Cleans the brakes.
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QUESTION 3 / 25
Air tank drains:
Choose one answer below.
A
Allow rain water to enter the tanks.
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B
Are used to drain water and oil from the tanks.
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C
Should never be opened.
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D
Must remain open while driving.
✓
QUESTION 4 / 25
When inspecting your brakes, a slack adjuster should move ____ from where it is attached to the push rod.
Choose one answer below.
A
At least three inches
✓
B
More than two inches
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C
Up to five inches
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D
No more than one inch
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QUESTION 5 / 25
Most heavy-duty vehicles use:
Choose one answer below.
A
Single air brake systems.
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B
Dual air brake systems.
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C
Triple air brake systems.
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D
Quadruple air brake systems.
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QUESTION 6 / 25
During a static leakage test, the maximum leakage rate for a single vehicle with air brakes is ____ in one minute.
Choose one answer below.
A
1 psi
✓
B
2 psi
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C
3 psi
✓
D
4 psi
✓
QUESTION 7 / 25
In a dual air brake system, a leak in one system:
Choose one answer below.
A
Always means there are leaks in both systems.
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B
May not affect the other system.
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C
Is not something to worry about.
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D
Will also affect the other system.
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QUESTION 8 / 25
Test the low pressure warning signal:
Choose one answer below.
A
Once a month.
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B
Once a week.
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C
Twice a week.
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D
Before every trip.
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QUESTION 9 / 25
When about to drive a vehicle with a dual brake system, a driver should:
Choose one answer below.
A
Let the vehicle warm up to ensure the fuel reaches the engine.
✓
B
Wait for air pressure to build in both the primary and secondary systems.
✓
C
Begin driving just after the engine starts.
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D
Pump the pedal about 20 times to build pressure, then begin driving.
✓
QUESTION 10 / 25
In a dual air brake system:
Choose one answer below.
A
Each system has separate air tanks, hoses, and lines.
✓
B
The systems share air tanks, but each has its own separate hoses and lines.
✓
C
Each system uses the same lines and hoses.
✓
D
One system is the main braking system and a second system is ready to be used if the first one fails.
✓
QUESTION 11 / 25
If you’re driving and the ABS warning light comes on, it means:
Choose one answer below.
A
The ABS is working properly.
✓
B
The ABS has just been activated.
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C
The ABS is not working properly.
✓
D
The ABS needs to be activated.
✓
QUESTION 12 / 25
When traveling down a steep downgrade:
Choose one answer below.
A
The air brakes should be used.
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B
Shift into a lower gear, then use brakes to supplement the braking effect of the engine.
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C
The vehicle should be continually downshifted in the place of using the brakes.
✓
D
The vehicle should be driven on the shoulder.
✓
QUESTION 13 / 25
If the spring brakes are on, you should:
Choose one answer below.
A
Not use the brake pedal.
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B
Press the accelerator.
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C
Move the steering wheel.
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D
Be especially careful because the brakes may fail.
✓
QUESTION 14 / 25
If your tractor is equipped with ABS but your trailer is not, the ABS:
Choose one answer below.
A
Will not be effective.
✓
B
Will still improve your steering control.
✓
C
Will make jackknifing easier.
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D
Will allow others to see when you brake.
✓
QUESTION 15 / 25
The most common type of foundation brake used is the:
Choose one answer below.
A
S-cam drum brake.
✓
B
C-cam drum brake.
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C
G-cam disc brake.
✓
D
P-cam disc brake.
✓
QUESTION 16 / 25
During a static leakage test, the maximum leakage rate for a triple combination vehicle with air brakes is ____ in a minute.
Choose one answer below.
A
3 psi
✓
B
5 psi
✓
C
7 psi
✓
D
9 psi
✓
QUESTION 17 / 25
What can happen if the air pressure gets too low in an air brake system?
Choose one answer below.
A
The brakes may squeak.
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B
The brakes may not work.
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C
The brakes may be sluggish.
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D
The brakes will be very sensitive.
✓
QUESTION 18 / 25
A low air pressure warning signal should activate:
Choose one answer below.
A
When tank pressure falls below 120 psi.
✓
B
When tank pressure falls below 60 psi.
✓
C
When tank pressure falls below 10 psi.
✓
D
When tank pressure falls below 5 psi.
✓
QUESTION 19 / 25
Do not use the parking brake when parking if:
Choose one answer below.
A
The brakes are very hot.
✓
B
The brakes are very cold.
✓
C
There is snow on the ground.
✓
D
There is water on the ground.
✓
QUESTION 20 / 25
The emergency brake system uses:
Choose one answer below.
A
Only parts of the parking brake system.
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B
Only parts of the service brake system.
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C
Parts of both the parking and service brake systems.
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D
Only parts unique to the emergency brake system.
✓
QUESTION 21 / 25
A vehicle equipped with an Anti-Lock Braking System (ABS) uses a ____ light to warn that the system is not working properly.
Choose one answer below.
A
Green
✓
B
Yellow
✓
C
Orange
✓
D
White
✓
QUESTION 22 / 25
A tank endorsement is:
Choose one answer below.
A
Only required when transporting gases.
✓
B
Only required when transporting liquids.
✓
C
Required to transport both liquids and gases.
✓
D
Optional when transporting hazardous materials.
✓
QUESTION 23 / 25
The ____ tells a driver how much pressure is in the air tanks.
Choose one answer below.
A
Application pressure gauge
✓
B
Air compressor governor
✓
C
Supply pressure gauge
✓
D
Drum brake
✓
QUESTION 24 / 25
If braking at a speed of 55 mph while driving on dry pavement, the brake lag can add ____ to your vehicle's total stopping distance.
Choose one answer below.
A
32 feet
✓
B
15 feet
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C
50 feet
✓
D
10 feet
✓
QUESTION 25 / 25
When the spring brakes are activated in a vehicle with air brakes, you should never:
Choose one answer below.
A
Turn on the lights.
✓
B
Turn the vehicle off.
✓
C
Push the brake pedal down.
✓
D
Open the trailer doors.
✓
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