Correct
Q.1)
The safety valve in the air compressor tank is set to open at...

A.
150 psi (Your Answer) B.
200 psi C.
100 psi D.
175 psi
Incorrect
Q.2)
Your vehicle's single brake system needs adjustment if...

A. pressure builds from 50 to 75 psi within three minutes B. pressure builds from 85 to 100 psi within 45 seconds (Your Answer) C. the compressor cuts out between 70 to 90 psi (Answer) D. the governor stops between 75 to 90 psi
Incorrect
Q.3)
Air tanks should be drained...

A.
Once a week B.
Once a day (Answer) C.
Every four hours (Your Answer) D.
Every two or three days
Correct
Q.4)
Brake drums...

A.
Are bolted to the wheels B.
Are located at each end of the vehicle's axles C.
Hold the brake shoes and linings D.
All of the above (Your Answer)
Incorrect
Q.5)
When the safety valve releases air it means that...

A.
The pressure has exceeded 150 psi B.
Too much air is in the air compressor C.
Something is wrong, and you should have it checked by a mechanic(Your Answer) D.
All of the above (Answer)
Incorrect
Q.6)
Compressed air is stored...

A.
In the hoses B.
In the engine compartment (Your Answer) C.
In the fuel tank D.
In the storage tank (Answer)
Incorrect
Q.7)
In a single vehicle with a fully charged air system, air pressure loss (after the initial drop and brake applied) should be less than...

A.
2 psi per minute (Your Answer) B.
3 psi per minute (Answer) C.
4 psi per minute D. none of the above
Incorrect
Q.8)
Some air brake systems have an alcohol evaporator which helps...

A.
Reduce the risk of ice in the air brake valves during cold weather(Answer) B.
Remove oil from the air lines C.
Reduce the risk of water in the air brake valves in warm weather (Your Answer) D.
Remove fuel from the air lines
Incorrect
Q.9)
The service brake system...

A. is an official vehicle inspection B. applies and releases the brakes by using the brake pedal under normal driving (Answer) C. are the valves that keeps the air tank pressure serviced D. is only on vehicles with hydraulic brakes (Your Answer)
Incorrect
Q.10)
When the low pressure warning is activated, you should...

A.
Wait for the air brakes to come on automatically B.
Bring the vehicle to a safe stop while you still control the brakes(Answer) C.
Monitor your air pressure gauge and maintain highway speeds (Your Answer) D.
-------------------------------------------------
Pump the brake pedal hard to stop
Your Answers
Incorrect
Q.1)
An emergency brake...

A.
Is required on commercial vehicles (Your Answer) B.
Must be held on by mechanical force C.
Could be activated by the loss of air pressure D.
All of the above (Answer)
Correct
Q.2)
To test the air leakage rate you should...

A.
Leave the engine running and release the service brake B.
Turn off the engine and release the service brake (Your Answer) C.
Charge the air system and leave the engine running D.
Depress the brake pedal and monitor the air pressure gauge
Incorrect
Q.3)
To check the air compressor governor "cut in" and "cut out" pressures...

A.
Run the engine at a fast idle B.
Step on and off the brake to reduce tank pressure C.
Monitor the air pressure gauge (Your Answer) D.
All of the above (Answer)
Incorrect
Q.4)
To test the low pressure warning signal, you should do all BUT the following...

A.
Shut the engine off B.
Turn the electrical power on C.
Ask a friend to listen for the signal (Answer) D.
Step on and off the brake pedal to reduce air pressure (Your Answer)
Incorrect
Q.5)
With dual air systems, the air pressure should build...

A.
From 85 to 100 psi in 45 seconds (Answer) B.
From 70 to 100 psi in 60 seconds (Your Answer) C.
From 85 to 150 psi in 45 seconds D.
From 70 to 150 psi in 60 seconds
Incorrect
Q.6)
When testing air leakage rates for combination vehicles (before applying the brake pedal), air brake systems should not lose air faster than...

A.
2 psi per minute (Your Answer) B.
3 psi per 30 seconds C.
3 psi per minute (Answer) D.
4 psi per minute
Incorrect
Q.7)
A dual air brake system...

A.
Has two air brake systems and one set of controls (Answer) B.
Takes less time to build air pressure C.
Has one set of air tanks and hoses (Your Answer) D.
Must have two warning alarms
Correct
Q.8)
To check the slack adjusters on S-Cam brakes, you should..

A.
Leave the parking brakes on and pull on the slack adjuster B.
Wear gloves and pull hard on each slack adjuster (Your Answer) C.
Make sure the slack adjusters move more than one inch each way D.
Drain the air from the system and pull on the slack adjusters
Incorrect
Q.9)
The Air Compressor Governor controls...

A.
When the brakes should be applied B.
When the air compressor pumps air into the storage tanks (Answer) C.
When the warning light is activated (Your Answer) D.
When the air is released from the tank
Incorrect
Q.10)
A fully charged air system typically has ____ psi.

A.
100

B.
125 (Answer) C.
150

D.
-------------------------------------------------
175 (Your Answer)
Your Answers
Incorrect
Q.1)
If your air compressor stops working...

A. you will lose your brakes immediately (Your Answer) B. the brakes will immediately lock up C. you'll still have air pressure left in the air tanks (Answer) D. your brakes won't be affected
Incorrect
Q.2)
The governor stops pumping air when it reaches the "cut out" level, or around...

A.
125 psi (Answer) B.
200 psi (Your Answer) C.
225 psi D.
175 psi
Correct
Q.3)
Slack adjusters...

A. never need to be adjusted B. should only be adjusted by a qualified mechanic C. can be adjusted manually or automatically (Your Answer) D. should travel at least two inches from where the push rod is attached
Incorrect
Q.4)
Air tanks should be drained...

A. at the end of each day or shift B. to keep sludge from clogging brake system valves C. manually when automatic devices fail (Your Answer) D.
All of the above (Answer)
Correct
Q.5)
You should not use the parking brakes...

A. on a steep hill B. if the air pressure is low C. when the brakes are hot (Your Answer) D. in hot weather
Incorrect
Q.6)
To determine if slack adjusters need adjustment...

A. apply the service brakes and release the parking brakes B. apply both the service and parking brakes C. pull out the automatic slack adjustment control knob (Your Answer) D. release both the service and parking brakes (Answer)
Correct
Q.7)
The brake drums or discs..

A. must have linings that fit loosely on the brake shoes B. must not have any cracks C. must not have cracks longer than half the width of the friction area (Your Answer) D. should be kept well-greased
Correct
Q.8)
An air tank is equipped with a drain valve to remove...

A.
Air and water B.
Oil and air C.
Water and oil (Your Answer) D.
Dirt and oil
Incorrect
Q.9)
Fanning air brakes...

A. cools them off B. increases the air pressure C. increases the braking power (Your Answer) D. decreases the air pressure (Answer)
Correct
Q.10)
The governor allows the air to start pumping again when it reaches the cut in level, or around...

A.
200 psi B.
100 psi (Your Answer) C.
150 psi D.
-------------------------------------------------
125 psi
Your Answers
Incorrect
Q.1)
The driver must be able to see a warning that is given before air pressure in the service air tanks falls below:

A.
80 psi (Your Answer) B.
40 psi C.
20 psi D.
60 psi (Answer)
Incorrect
Q.2)
The most common type of foundation brakes found on heavy vehicles is the:

A.
Disc brakes B.
Wedge drum (Your Answer) C.
S-cam drum (Answer) D.
None of the above
Correct
Q.3)
If the air compressor should develop a leak, what keeps the air in the tanks?

A.
The tractor protection valve B.
The emergency relay valve C.
The one way check valve (Your Answer) D.
The air compressor
Correct
Q.4)
When driving down a long steep hill you should:

A.
Use stab braking. B.
Begin braking when you are 10 M.P.H. above your safe speed. C.
Release the brake when you are 5 M.P.H. below your safe speed. (Your Answer) D.
Use the trailer brakes.
Incorrect
Q.5)
To check the free play of manual slack adjusters on s-cam brakes you should:

A.
Park on level ground, chock the wheels, and release the parking brakes.(Answer) B.
Stop on level ground and apply the parking brakes. C.
Park on level ground and drain off air pressure before adjusting. (Your Answer) D.
Park on a slight grade, release the parking brake, apply the service brakes, and check for vehicle movement.
Incorrect
Q.6)
To make an emergency stop with air brakes, using the stab braking method, you should:

A.
Pump the brake pedal rapidly and lightly. B.
Brake hard until the wheels lock, and then get off the brakes for as much time as the wheels were locked (Your Answer) C.
Brake as hard as you can, get off the brakes when the wheels lock, get back on the brakes when the wheels start rolling again. (Answer) D.
Press hard on the brake pedal and apply full hand valve until you stop.
Correct
Q.7)
Air loss in a straight truck or bus should not be more than ____ with the engine off and the brakes released.

A.
1 psi in 30 seconds B.
1 psi in one minute C.
2 psi in one minute (Your Answer) D.
3 psi in one minute
Incorrect
Q.8)
The brake system that applies and releases the brakes when the driver uses the brake pedal is the:

A.
Service brake system. (Answer) B.
Emergency brake system. C.
Parking brake system. D.
None of the above. (Your Answer)
Incorrect
Q.9)
You should know that your brakes are fading when:

A.
Pressure on the brake pedal is released and speed increases. B.
You have to push harder on the brake pedal to control your speed on a downgrade. (Answer) C.
The brake feels spongy when pressure is applied (Your Answer) D.
Less pressure is needed on the brake pedal for each stop
Incorrect
Q.10)
Vehicles with air brakes must have:

A.
At least two air tanks. B.
An air pressure gauge to show the pressure available for braking.(Answer) C.
An air pressure gauge, to show air used by the brake chambers for braking. D.
-------------------------------------------------
None of the above. (Your Answer)
Correct
Q.1)
Air braking takes more time than hydraulic braking because air brakes:

A.
Need to have airflow through the lines to work. (Your Answer) B.
Use different brake drums. C.
Require heavier return springs. D.
All of the above.
Correct
Q.2)
If your truck or bus has dual parking control valves it means that you can use pressure from a separate tank to:

A.
Balance the service brake system. B.
Release the spring brakes to move a short distance. (Your Answer) C.
Stay parked without using up service air pressure. D.
Apply more brake pressure if the main tank is getting low.
Incorrect
Q.3)
The brake pedal in an air brake system:

A.
Is to be used as a footrest during normal driving. B.
Controls the speed of the air compressor. (Your Answer) C.
Controls the air pressure applied to put on the brakes. (Answer) D.
Is connected to slack adjusters by a series of rods and linkages.
Incorrect
Q.4)
During normal driving, spring brakes are usually held back by:

A.
Spring pressure B.
Bolts or clamps C.
Centrifugal force (Your Answer) D.
Air pressure (Answer)
Correct
Q.5)
If you must make an emergency stop, you should brake so that you:

A.
Use the full power of the brakes and lock them. B.
Can steer hard while braking hard. C.
Stay in a straight line and can steer. (Your Answer) D.
Use the hand brake first.
Incorrect
Q.6)
Your truck or bus has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?

A.
Reduce your speed and drive to the nearest garage for repairs. B.
Continue at normal speed and find a garage before the brakes lock. (Your Answer) C.
Reduce your speed and test the remaining system while under way. D.
Stop. Safely park, and continue only after the system is fixed. (Answer)
Incorrect
Q.7)
A straight truck or bus air brake system should not leak at a rate of more than ____ PSI per minute with the engine off and the brakes released.

A.
4

B.
3 (Your Answer) C.
2 (Answer) D.
1
Incorrect
Q.8)
If your vehicle has an alcohol evaporator, it is there to:

A.
Reduce the risk of ice in air brake valves in cold weather. (Answer) B.
Eliminate the need for daily tank draining. C.
Rid the wet tank of alcohol that condenses and sits at the bottom. (Your Answer) D.
Boost tank pressure the same way that superchargers boost.
Correct
Q.9)
If your vehicle has an alcohol evaporator, every day during cold weather you should:

A.
Clean the air filter with alcohol. B.
Check and fill the alcohol level. (Your Answer) C.
Change the alcohol from a new bottle. D.
Check the oil for alcohol content.
Incorrect
Q.10)
In air brake vehicles, the parking brakes should be used:

A.
To hold your speed when going downhill. B.
Whenever the vehicle is parked. (Answer) C.
As little as possible. (Your Answer) D.
-------------------------------------------------
Only during pre and post trip inspections.
Correct
Q.1)
When you apply pressure to the brake pedal, you are...

A.
Pushing against a spring and against air pressure to the brakes (Your Answer) B.
Releasing air pressure to the brakes C.
Reducing air in the tanks D.
Activating the safety valve
Incorrect
Q.2)
Air brakes take longer to stop than hydraulic brakes because...

A.
The reaction time is longer for the driver (Your Answer) B.
It takes longer for the air to flow through the lines (Answer) C.
The linings get hotter more quickly D.
None of the above
Incorrect
Q.3)
Which type of brake is the most common in commercial vehicles?

A.
Wedge brakes (Your Answer) B.
Disc brakes C.
S Cam brakes (Answer) D.
Drum brakes
Incorrect
Q.4)
The proper way to go down long grades is to...

A.
Use a low gear and push hard on the brakes (Your Answer) B.
Let up on the brakes from time to time to cool them C.
Use a low gear and apply constant, light pressure on the brakes D.
Apply brakes just hard enough to reduce speed to five mph below safe speed then release until back to safe speed and repeat process.(Answer)
Incorrect
Q.5)
To test your service brakes you should...

A.
Stop the vehicle and put the parking brake on (Your Answer) B.
Release the parking brake, move forward slowly and depress brakes(Answer) C.
Put parking brake on and release air pressure D.
Depress brakes when traveling at highway speeds
Incorrect
Q.6)
The air compressor is connected to the engine through...

A.
Gears (Your Answer) B.
Hoses

C.
V-Belt

D.
Gears or a v-belt (Answer)
Incorrect
Q.7)
All vehicles with air brakes are required to have a low pressure warning signal. This could be...

A.
A red light (Your Answer) B.
A wig wag mechanical arm C.
A buzzer D.
Any one of the above (Answer)
Incorrect
Q.8)
Stab braking occurs when you...

A.
Press on the brake pedal all the way (Your Answer) B.
Release the brakes when the wheels lock up C.
Apply the brakes when the wheels start rolling D.
All of the above (Answer)
Incorrect
Q.9)
You should avoid using the parking brake...

A. on steep hills (Your Answer) B. if the air pressure is low C. when the brakes are hot (Answer) D. any time you park
Correct
Q.10)
An application pressure gauge...

A.
Shows how much air pressure you are applying to the brakes (Your Answer) B.
Is connected to the generator C.
Releases air when you accelerate D.
-------------------------------------------------
Prevents brake failure
Incorrect
Q.1)
The braking power of the spring brakes:

A.
Can only be tested by highly trained brake service people. (Your Answer) B.
Depends on the adjustment of the service brakes. (Answer) C.
Increases when the service brakes are hot. D.
Is not affected by the condition of the service brakes.
Incorrect
Q.2)
Modern air brake systems combines three different systems. The are the service brakes, the parking brakes and the:

A.
S-cam brakes. (Your Answer) B.
Drum brakes. C.
Foot brakes. D.
Emergency brakes. (Answer)
Correct
Q.3)
Which of the following makes the total stopping distance for air brakes longer than that for hydraulic brakes.

A.
Brake lag distance. (Your Answer) B.
Action distance. C.
Perception distance. D.
Effective braking distance.
Incorrect
Q.4)
What can legally hold a parking or emergency brake in position for a truck, truck tractor or bus?

A.
Fluid pressure (Your Answer) B.
Air pressure C.
Spring pressure (Answer) D.
Any of the above
Incorrect
Q.5)
The air compressor governor controls:

A.
When air is pumped into the air tanks. (Answer) B.
Air pressure applied to the brakes. (Your Answer) C.
The speed of the air compressor. D.
When the brake chambers release pressure.
Incorrect
Q.6)
The application pressure gauge shows the driver how much pressure:

A.
Has been used on the trip. (Your Answer) B.
Is in the air tanks. C.
Is being applied to the brakes. (Answer) D.
None of these.
Correct
Q.7)
Oil and water usually collect in compressed air tanks. If you do not have an automatic tank drain, when should you drain the air tanks?

A.
After every working day. (Your Answer) B.
After every four hours of service. C.
Once a week. D.
Every other week.
Correct
Q.8)
Why drain water from the compressed air tanks?

A.
To keep from fouling the air compressor oil. B.
Water can freeze in cold weather and cause brake failure. (Your Answer) C.
The low boiling point of water reduces braking power. D.
Water over cools the compressor.
Incorrect
Q.9)
Air brake equipped vehicles must have:

A.
A supply pressure gauge. (Answer) B.
An air use gauge. (Your Answer) C.
At least two brake heaters. D.
A backup hydraulic system.
Incorrect
Q.10)
Of the choices below, the first thing to do when a low air pressure warning comes on is:

A.
Open the air supply control valve. B.
Adjust the brake pedal for more travel. (Your Answer) C.
Stop and safely park as soon as possible. (Answer) D.
-------------------------------------------------
Up-shift.