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Illinois CDL Air Brakes Test 1
Practice mode
Question
1
of 25
QUESTION 1 / 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.
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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 2 / 25
Using an Anti-Lock Braking System (ABS):
Choose one answer below.
A
Shortens stopping distance.
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B
Shortens brake response time.
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C
Provides less control.
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D
Provides more control.
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QUESTION 3 / 25
If the low pressure warning light comes on while you are driving:
Choose one answer below.
A
Braking will only occur if there is enough air in the tanks.
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B
You can brake 14 times before the air in the system runs out.
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C
You should continue to drive normally and check the brake system when it is convenient.
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D
You should continue driving, but turn the emergency flashers on to warn other motorists.
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QUESTION 4 / 25
All air tanks must include:
Choose one answer below.
A
A drain valve.
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B
A lock.
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C
A trap door.
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D
A warning sticker.
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QUESTION 5 / 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.
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QUESTION 6 / 25
How should you test the low pressure warning signal?
Choose one answer below.
A
Engage and disable the parking brake.
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B
Rapidly press and release the brake pedal.
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C
Open the rear shut-off valves.
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D
Uncouple and recouple all glad hands.
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QUESTION 7 / 25
Air pressure should build up in a single air system within:
Choose one answer below.
A
15 minutes.
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B
12 minutes.
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C
Three minutes.
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D
One minute.
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QUESTION 8 / 25
During an applied leakage test, the maximum leakage rate for a double combination vehicle is:
Choose one answer below.
A
10 psi in a minute.
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B
8 psi in a minute.
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C
6 psi in a minute.
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D
4 psi in a minute.
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QUESTION 9 / 25
The parking brake should be:
Choose one answer below.
A
Used whenever you park the vehicle.
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B
Used while driving.
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C
Set when driving in bad weather.
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D
Used to stop the vehicle in normal driving.
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QUESTION 10 / 25
Water and compressor oil are usually found in the compressed air within an air brake system. Water and compressor oil:
Choose one answer below.
A
Are necessary for the proper function of the air brake system.
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B
Should be added if low.
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C
Should be removed regularly.
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D
Are not concerns.
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QUESTION 11 / 25
An Anti-Lock Braking System (ABS):
Choose one answer below.
A
Cannot be used with air brakes.
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B
Should be used on dry pavement.
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C
Can assist in maintaining control when braking.
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D
Should only be used if all axles have ABS.
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QUESTION 12 / 25
A one-way check valve:
Choose one answer below.
A
Drains the water and compressor oil from the air tanks.
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B
Prevents air from escaping if the air compressor has a leak.
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C
Activates the emergency brakes when there is a leak.
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D
Holds the spring brakes in position until they are used.
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QUESTION 13 / 25
If the spring brakes are activated, you should never:
Choose one answer below.
A
Push down the brake pedal.
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B
Open the hood.
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C
Release air from the air storage tanks.
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D
Open the door to the cab.
✓
QUESTION 14 / 25
If you’re driving and the ABS warning light comes on, it means:
Choose one answer below.
A
The ABS is working properly.
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B
The ABS has just been activated.
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C
The ABS is not working properly.
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D
The ABS needs to be activated.
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QUESTION 15 / 25
What can happen if a parking brake is used in very wet weather when temperatures are below freezing?
Choose one answer below.
A
The brakes will squeak.
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B
The brakes may freeze so the vehicle cannot move.
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C
The brakes may suddenly release by themselves.
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D
The brakes may explode.
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QUESTION 16 / 25
When using the controlled braking method in an emergency situation, you should:
Choose one answer below.
A
Apply the brakes as hard as possible without locking the wheels.
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B
Apply the brakes with about half of your usual force.
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C
Apply the brakes so the wheels lock.
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D
Apply the brakes with minimal pressure.
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QUESTION 17 / 25
Truck tractors with air brakes that were built on or after March 1, 1997 are equipped with:
Choose one answer below.
A
An extra set of brakes.
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B
Voice-activated brakes.
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C
Cruise control.
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D
Anti-Lock Braking Systems (ABS).
✓
QUESTION 18 / 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.
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QUESTION 19 / 25
Foundation brakes are used:
Choose one answer below.
A
Only at the front wheels.
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B
Only at the rear wheels.
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C
Only at the driver’s side wheels.
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D
At each wheel.
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QUESTION 20 / 25
The air storage tanks:
Choose one answer below.
A
Hold only enough air for one braking cycle.
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B
Hold enough air for brakes to be used several times if the compressor stops working.
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C
Do not hold air unless there is an emergency.
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D
Hold enough air for more than 1,000 braking cycles.
✓
QUESTION 21 / 25
A dual air brake system:
Choose one answer below.
A
Has a single air brake system, but uses two sets of controls.
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B
Has one air brake system for each side of the truck.
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C
Has two brakes for each wheel.
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D
Has two separate air brake systems, but uses a single set of controls.
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QUESTION 22 / 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
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B
15 feet
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C
50 feet
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D
10 feet
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QUESTION 23 / 25
To use the stab braking method, you should:
Choose one answer below.
A
Apply the brakes completely until the wheels lock up, release the brakes until the wheels start rolling, then repeat the process.
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B
Apply the brakes about halfway, but allow the wheels to keep rolling.
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C
Apply the brakes completely until the wheels lock up and the vehicle stops.
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D
Apply the emergency brake until the vehicle starts to slow.
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QUESTION 24 / 25
Brake fading is caused when:
Choose one answer below.
A
Brakes are not used often enough.
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B
Brakes overheat.
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C
Brakes are too cold.
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D
Brakes are wet.
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QUESTION 25 / 25
If using air tanks with manually operated drains, how often should you drain the tanks?
Choose one answer below.
A
Every day
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B
Once a week
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C
Once a month
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D
Once every 3,000 miles
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