The time required for the brakes to work after the brake pedal is pushed

The distance between the brake pedal’s resting position and the floor

The amount of air pressure used to stop a vehicle

Indiana CDL Air Brakes 1 - DMV Written Test Questions with Answers

Q.1

If the spring brakes are activated, you should never:

Push down the brake pedal.
Open the hood.
Release air from the air storage tanks.
Open the door to the cab.

Q.2

If the spring brakes are on, you should:

Not use the brake pedal.
Press the accelerator.
Move the steering wheel.
Be especially careful because the brakes may fail.

Q.3

When only the tractor is equipped with an Anti-Lock Braking System (ABS):

There is a decreased risk of jackknifing.
There is an increased risk of jackknifing.
The brakes will not work as effectively as they would without ABS.
The brakes will become more sensitive.

Q.4

In a dual air brake system, a leak in one system:

Always means there are leaks in both systems.
May not affect the other system.
Is not something to worry about.
Will also affect the other system.

Q.5

How is the parking brake released?

By tapping the brake pedal three times
By pushing in the brake control knob
By starting the vehicle
By tapping the accelerator twice

Q.6

In a dual air brake system:

Each system has separate air tanks, hoses, and lines.
The systems share air tanks, but each has its own separate hoses and lines.
Each system uses the same lines and hoses.
One system is the main braking system and a second system is ready to be used if the first one fails.

Q.7

If the air pressure warning light comes on, you should:

Continue driving normally.
Activate your hazard lights and continue driving.
Call the local law enforcement agency.
Safely exit the roadway and stop.

Q.8

How many air storage tanks are used in an air brake system?

Two tanks
Four tanks
Six tanks
The number varies.

Q.9

Before driving a vehicle with a dual air brake system, you must wait for the air compressor to build a minimum of ____ in both the primary and secondary systems.

25 psi
50 psi
75 psi
100 psi

Q.10

In cold weather, an alcohol evaporator should be checked and filled:

Once a week.
Every day.
Every hour.
Once a month.

Q.11

Brake fading is caused when:

Brakes are not used often enough.
Brakes overheat.
Brakes are too cold.
Brakes are wet.

Q.12

To confirm that a trailer has ABS, you can:

Look under the trailer for wheel speed sensors coming from the back of the brakes.
Look under the hood for the ABS sticker.
Look at the tires.
Remove a tire and look for the ABS sensor on the axle.

Q.13

While driving, spring brakes are generally held in place by:

Air pressure.
Chocks.
Foundation brakes.
Sturdy ties.

Q.14

The parking brake should be:

Used whenever you park the vehicle.
Used while driving.
Set when driving in bad weather.
Used to stop the vehicle in normal driving.

Q.15

An Anti-Lock Braking System (ABS):

Cannot be used with air brakes.
Should be used on dry pavement.
Can assist in maintaining control when braking.
Should only be used if all axles have ABS.

Q.16

Water and compressor oil are usually found in the compressed air within an air brake system. Water and compressor oil:

Are necessary for the proper function of the air brake system.
Should be added if low.
Should be removed regularly.
Are not concerns.

Q.17

During a static leakage test, the maximum leakage rate for a double combination vehicle is:

3 psi in one minute.
6 psi in one minute.
8 psi in one minute.
4 psi in one minute.

Q.18

To ensure normal stopping power, drivers of vehicles equipped with a front brake limiting valve should:

Set the control to normal.
Set the control to the off position.
Set the control to neutral.
Keep the control at the halfway mark.

Q.19

What can happen if the air pressure gets too low in an air brake system?

The brakes may squeak.
The brakes may not work.
The brakes may be sluggish.
The brakes will be very sensitive.

Q.20

What is brake lag?

The time required for the brakes to work after the brake pedal is pushed
The distance between the brake pedal’s resting position and the floor
The amount of air pressure used to stop a vehicle
How faded the brakes are

Q.21

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.

32 feet
15 feet
50 feet
10 feet

Q.22

During an applied leakage test, the maximum leakage rate for a single vehicle with air brakes is:

3 psi in one minute.
6 psi in one minute.
8 psi in one minute.
4 psi in one minute.

Q.23

Applying the brake pedal causes air pressure to activate an electric switch and:

Turn off the brake lights.
Turn on the low pressure warning light.
Turn on the brake lights.
Turn off the low pressure warning light.

Q.24

What color is the low air pressure warning light?

Green
Orange
Red
Purple

Q.25

Friction inside a brake drum is caused when the brake shoes and linings:

Push against each other.
Separate from the axle.
Push against the inside of the drum.
Create excess heat.