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Michigan CDL - Air Brakes Practice Exam
Practice mode
Question
1
of 25
QUESTION 1 / 25
Why is it crucial to check brake lining thickness?
Choose one answer below.
A
To ensure that the brakes are visually appealing
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B
To ensure that the brakes have sufficient friction material for safe stopping
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C
To maintain the brake drums in good condition
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D
To comply with regulatory standards
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QUESTION 2 / 25
What is a common issue that can occur with air brake systems?
Choose one answer below.
A
Fluid leakage
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B
Air leaks
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C
Electrical failures
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D
Excessive heat
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QUESTION 3 / 25
What is a common sign of a malfunctioning air brake system?
Choose one answer below.
A
Increased stopping distance
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B
Reduced noise from the brakes
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C
Quicker brake response
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D
Better fuel efficiency
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QUESTION 4 / 25
How often should the alcohol evaporator be checked and filled in cold weather?
Choose one answer below.
A
Every week
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B
Every day
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C
Every trip
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D
Every month
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QUESTION 5 / 25
What type of maintenance does the air dryer require?
Choose one answer below.
A
Regular cleaning of the filter
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B
Regular replacement of the desiccant element
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C
Periodic inspection of the air lines
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D
Adjustment of the brake pads
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QUESTION 6 / 25
How can a driver prevent freeze-ups in the air brake system?
Choose one answer below.
A
By increasing the air pressure regularly
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B
By using alcohol evaporators or dehumidifiers in the air system
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C
By ensuring all hoses are insulated
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D
By avoiding heavy braking in cold conditions
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QUESTION 7 / 25
How often should the air tanks be drained?
Choose one answer below.
A
Weekly, to maintain optimal performance
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B
Annually, during inspections
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C
Regularly, usually daily, to remove moisture and contaminants
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D
Only when there is a visible clog
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QUESTION 8 / 25
What is the maximum allowable crack length on a brake drum during a walk-around inspection?
Choose one answer below.
A
One quarter of the width of the friction area
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B
One half of the width of the friction area
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C
Three quarters of the width of the friction area
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D
Full width of the friction area
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QUESTION 9 / 25
Which type of air brake system is most prevalent in commercial vehicles?
Choose one answer below.
A
Single air brake system
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B
Hydraulic brake system
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C
Dual air brake system
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D
Electronic brake system
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QUESTION 10 / 25
What is the effect of a clogged air filter in the air brake system?
Choose one answer below.
A
Increased braking efficiency
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B
Higher air pressure in the system
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C
Reduced airflow to the compressor, leading to inadequate brake function
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D
Quicker brake response time
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QUESTION 11 / 25
What is the minimum air pressure required for safe operation of air brakes?
Choose one answer below.
A
30 psi
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B
60 psi
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C
80 psi
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D
100 psi
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QUESTION 12 / 25
What may cause the air in the brake lines to freeze?
Choose one answer below.
A
Excessive heat in the brake system
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B
Moisture in the air system that condenses and freezes in cold temperatures
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C
Contaminants in the brake fluid
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D
Lack of air pressure in the system
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QUESTION 13 / 25
How can a driver determine if the air brake system is functioning properly during a road test?
Choose one answer below.
A
By performing the brake application and release test and verifying responsiveness
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B
By assessing tire pressure and tread depth
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C
By checking the engine oil levels
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D
By monitoring fuel consumption during the drive
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QUESTION 14 / 25
How can you confirm that a trailer is equipped with ABS?
Choose one answer below.
A
Check the tires for wear
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B
Look under the trailer for wheel speed sensors
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C
Inspect the trailer's exterior for ABS stickers
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D
Consult the owner's manual
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QUESTION 15 / 25
How can a driver identify a blown air line?
Choose one answer below.
A
By checking the brake pads for wear
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B
By inspecting for visible damage or listening for escaping air
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C
By observing unusual tire wear
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D
By checking the air filter condition
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QUESTION 16 / 25
How can a driver identify air leaks in the air brake system?
Choose one answer below.
A
By checking fluid levels regularly
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B
By listening for hissing sounds and monitoring pressure loss
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C
By inspecting brake pads for wear
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D
By observing the vehicle's exhaust emissions
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QUESTION 17 / 25
What might indicate that the slack adjuster needs adjustment?
Choose one answer below.
A
Consistent braking power
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B
Brakes are frequently overheating
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C
Inconsistent gap between shoes and drum
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D
No change in brake performance
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QUESTION 18 / 25
If the brakes pull to one side when applied, what should the driver do?
Choose one answer below.
A
Ignore the problem and continue driving
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B
Inspect for uneven wear or a malfunction
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C
Adjust the brake shoes manually
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D
Replace the entire braking system
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QUESTION 19 / 25
What could be an indicator that brake adjustment is needed?
Choose one answer below.
A
Reduced stopping power
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B
Increased tire wear
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C
Lighter pedal pressure requirement
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D
Frequent brake squeal noise
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QUESTION 20 / 25
What is the maximum leakage rate for a single vehicle with air brakes during a static leakage test?
Choose one answer below.
A
3 psi in one minute
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B
1 psi in one minute
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C
2 psi in one minute
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D
5 psi in one minute
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QUESTION 21 / 25
When should the air tanks be drained if they have a manual drain valve?
Choose one answer below.
A
At the beginning of each day
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B
Before refueling
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C
At the end of each day of driving
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D
Every week
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QUESTION 22 / 25
When conducting a rapid application of the brake pedal, what should occur?
Choose one answer below.
A
The warning signal comes on as pressure drops
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B
The air system becomes pressurized
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C
The vehicle should accelerate
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D
The brake lights will illuminate
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QUESTION 23 / 25
How long should it take for air pressure in a dual air brake system to build from 85 to 100 psi?
Choose one answer below.
A
30 seconds
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B
45 seconds
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C
60 seconds
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D
90 seconds
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QUESTION 24 / 25
How long should it take for air pressure to build in a single air system?
Choose one answer below.
A
Two minutes
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B
Three minutes
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C
Four minutes
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D
Five minutes
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QUESTION 25 / 25
How often should manually operated air tank drains be used to prevent oil and water buildup?
Choose one answer below.
A
Once a week
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B
Every day
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C
Once a month
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D
Every two weeks
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