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

The distance between the brake pedal and the floor

The amount of air pressure used to stop the vehicle

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

Q.1

To inspect slack adjusters on S-cam brakes, you need to:

Park on a hill and test the brakes.
Put on gloves and push in the slack adjusters.
Remove the drum and look inside.
Chock the wheels and disengage the parking brake.

Q.2

Failing to drain the tanks in an air brake system can result in:

Water freezing and causing brake failure.
Squishy brakes.
Too much air collecting.
Too much fuel being carried.

Q.3

When leaving your vehicle unattended:

The parking brake should be used.
The parking brake only needs to be used if the vehicle is parked on a slope.
The parking brake should not be used, as it can damage the tires.

Q.4

What is brake lag?

The time required for the brakes to work after the brake pedal is pressed
The distance between the brake pedal and the floor
The amount of air pressure used to stop the vehicle

Q.5

An air compressor governor will stop the compressor from pumping air once the air tanks have an air pressure level of:

125 psi.
100 psi.
150 psi.
80 psi.

Q.6

Having ABS on only one axle:

Can be dangerous.
Still allows you additional control when braking.
Slows the vehicle, but cannot stop it.

Q.7

To make a stop in a vehicle using air brakes, the driver should:

Press down the brake pedal.
Lift the brake pedal toward them.
Push in the brake knob.
Pull out the brake knob.

Q.8

What must be on an air tank in an air-braked vehicle?

A check valve
A lock
A trap door
An oxidizer

Q.9

On newer vehicles, how do you put on the parking brake?

Move a lever to the right.
Push in the yellow, diamond-shaped knob.
Pull out the yellow, diamond-shaped knob.
Pull up on the steering column.

Q.10

An Anti-Lock Braking System (ABS):

Is not available for vehicles with air brakes.
Is not helpful in most driving situations.
Can help you maintain control when braking.

Q.11

An emergency brake must be controlled by:

Mechanical force.
Air pressure.
Gravity.

Q.12

The emergency brake system uses:

Only parts of the parking brake system.
Only parts of the service brake system.
Parts of both the parking and service brake systems.
Only parts unique to the emergency brake system.

Q.13

In a vehicle with dual air brakes, what happens if one system is low on pressure?

The air from the other system will be used to supplement the system with the low pressure.
The front or rear brakes may not work properly.
All brakes will be inoperable.
The low system will use an auxiliary system to fill the tank.

Q.14

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.15

What should happen if the air pressure in the air brake system tanks falls below 60 psi?

A warning light should come on.
Lights should flash on the outside of the vehicle.
A message should appear on the control panel.
The vehicle should stop.

Q.16

An air brake-equipped vehicle traveling at a speed of 55 mph under ideal driving conditions will need approximately ____ to come to a complete stop.

100 feet
250 feet
300 feet
450 feet

Q.17

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.18

When traveling down a steep downgrade:

The air brakes should be used.
Shift into a lower gear, then use brakes to supplement the braking effect of the engine.
The vehicle should be continually downshifted in the place of using the brakes.
The vehicle should be driven on the shoulder.

Q.19

Using an Anti-Lock Braking System (ABS):

Is required in some states.
Shortens brake response time.
Provides additional control.

Q.20

If the brake pads rub against the brake drums and create too much heat:

The brakes will stick.
The brakes will become extra sensitive.
The brakes may stop working.
The air compressor will kick on to cool the brakes.

Q.21

When about to drive a vehicle with a dual brake system, a driver should:

Let the vehicle warm up to ensure the fuel reaches the engine.
Wait for air pressure to build in both the primary and secondary systems.
Begin driving just after the engine starts.
Pump the pedal about 20 times to build pressure, then begin driving.

Q.22

What do the two systems of a dual air brake system share?

Hoses
An air compressor
Air tanks

Q.23

Air brakes use ____ to function.

Compressed air
Liquid nitrogen
Carbon dioxide

Q.24

You should not use the parking brake:

If your vehicle is stopped on a level surface.
If your vehicle is stopped on a slight incline.
If your vehicle's brakes are very hot.
If your vehicle's other braking systems seem to be working adequately.

Q.25

To use the stab braking method, you should:

Apply the brakes completely until the wheels lock up, release the brakes until the wheels start rolling, then repeat the process.
Apply the brakes about halfway, but allow the wheels to keep rolling.
Apply the brakes completely until the wheels lock up and the vehicle stops.
Apply the emergency brake until the vehicle starts to slow.