CDL PRACTICE TEST AIR BRAKES – 04

We know that taking the air brakes test as part of your CDL permit can cause anxiety in even the most confident driver. That is why we designed this free cdl practice test air brakes so that you can practice and get an idea of what types of questions will be asked on the actual test at the DMV. We encourage you to take it as many times as you would like or until you get a perfect score. We hope that this practice test proves helpful as you study for your exam. Please visit us again and take all of our practice exams as often as you would like.

Air Brake Test 04

1 / 25

With your engine at operating RPM, in a dual air system the pressure should build from 85 to 100 psi within...?

75 seconds

60 seconds

45 seconds

25 seconds

2 / 25

Which of these is not part of an air brake system?

Emergency brake

Service brake

Aerodynamic brake

Parking brake

3 / 25

If the air pressure does not build fast enough after turning the engine on, you should...?

Not drive over 55 mph until the problem has been investigated

Not drive until the problem has been investigated

Report the problem to the operator

Report the problem for investigation at the next routine maintenance

4 / 25

The air compressor runs off...?

Its own battery

The wheels

The engine

External air pressure

5 / 25

A modulating control valve can be used to apply spring brakes...?

Gradually

Forcefully

Quickly

Instantly

6 / 25

In newer vehicles, parking brakes are controlled using a diamond shaped control knob of what color?

Red

Green

Blue

Yellow

7 / 25

Truck tractors with air brake systems will definitely have ABS if built after March 1...?

1999

1998

1997

2000

8 / 25

If the pressure drops at higher than the recommended rate when the engine is turned off and the parking brake released, it could be indicative of...?

Faulty compressor

Water in the system

Air leakage

Badly adjusted brakes

9 / 25

Which of the following statements are true?

You can leave your vehicle unattended without applying the parking brakes or chocking the wheels

Never leave your vehicle unattended without applying the parking brakes or chocking the wheels

10 / 25

In air brake vehicles, the parking brakes should be used...?

Only on emergencies

Any time the vehicle is parked

When parking uphill only

When parking downgrade only

11 / 25

Air brakes use what to function?

Air gathered from vents

Compressed air

Air flowing over a vehicle

Radiator inducted air

12 / 25

The brake pedal in an air brake system controls the air pressure applied to the brakes.

FALSE

TRUE

13 / 25

Spring brakes...?

Are held by mechanical force

Are held by S-cam drum

Are held by safety valve

Are held by brake drum

14 / 25

What protects the tank and the rest of the air system from too much pressure?

S-cam drum

Alcohol Evaporator

Safety valve

Air compressor governor

15 / 25

Emergency brake systems use...?

Parts of both the service and parking brake systems

Parts of the parking brake system

None of these

Parts of the service brake system

16 / 25

All air brake equipped vehicles have Air supply pressure gauge.

FALSE

TRUE

17 / 25

The modulating control valve allows you to control the...?

Emergency brakes

Spring brakes

Parking brakes

Service brakes

18 / 25

With the engine off and the parking brake released in a combination vehicle, the pressure should not drop by more than how many PSI per minute?

19 / 25

Service brakes are activated by...?

The parking brake lever

A dashboard switch

Any of these

The brake pedal

20 / 25

The most common type of foundation brake found on heavy vehicles is the...?

Slack adjuster

S-cam drum

Dual air brake

compressor governor

21 / 25

If you push the brake pedal down when the spring brakes are on, you are risking...?

Compressor damage

Damaging the engine

Damaging the brakes

Skidding

22 / 25

Separate air tanks to release the spring brakes when the main air brake system has failed should only be used...?

To get to a mechanic

In none of these situations

In emergencies

Once per trip

23 / 25

The main purpose of the alcohol evaporator is to put alcohol in the air system.

TRUE

FALSE

24 / 25

Once the air system is fully charged and you have turned off the engine and released the parking brake, in a single vehicle the pressure should not drop by more than how many PSI per minute?

25 / 25

During the walk-around inspection, if a slack adjuster moves slightly more than an inch where the push rod attaches to it, then...?

It probably needs adjustment

It should be remove

It probably needs replacement

It's fine

Your score is