Air Brakes Test 2

You should know that your brakes are fading when:

You have to push harder on the break pedals to control your speed on a downgrade

If the spring brakes are on, when should you push the brake pedal?

Never

The driver must be able to see a low air pressure warning, which comes on before pressure in the service air tanks falls below __ psi.

60

If your truck or bus has dual parking control valves, you can use pressure from a separate tank to:

Release the spring emergency/parking brakes to move a short distance

The brake pedal in an air brake system:

Controls the air pressure applied to put on the brakes

Parking or emergency brakes of trucks and buses can be legally held on by __ pressure:

Spring

The most common type of foundation brake found on heavy vehicle vehicles is the:

S-cam drum

If your truck has a dual air system, and one of the systems is low on pressure:

Either the front or rear brakes will not be fully operational

An air brake vehicles, the parking brakes should be used:

Any time the vehicle is parked

The air compressor governor controls:

When air pumped into the air tanks

The stop light switch:

Turns on the brake lights to warn drivers behind you

For air brake system systems in good condition, the air compressor should start pumping out about __ psi.

100

The air loss rate for a straight truck or a bus with the engine off, and the brakes on should not be more than:

3 psi in one minute

The braking power of the spring brakes:

Depends on the service brakes being in adjustments

How should you check that the spring brakes come on when air pressure in the system drops below a certain level?

Check the wheels, apply the parking brake, shut the engine off, and pump the brake pedal to reduce air tank pressure

If you are driving down a steep downgrade, and you have reached your “safe” speed of 40 MPH. You should apply the service brakes until speed drops to __ MPH.

35

The air brake lag distance at 55 MPH on dry pavement adds about __ feet to your stopping distance:

32

Repeatedly pressing and releasing (fanning) the brake pedal may result in:

The loss of brake air pressure

Emergency controlled braking is when you:

Apply the brake as hard as you can without locking the wheels

If your truck’s air compressor has its own oil supply, when should you first check the oil level?

Before driving