In this session, you will be able to find 330+ California CDL Air Brakes Practice test answers which will help you for the upcoming exams.
Please note that all answers will be revealed for free. So let’s get started right away!
- California CDL Air Brakes Practice Test Answers – 330+ Solved
- California CDL Air Brakes Practice Test Answers – Model 1
- California CDL Air Brakes Practice Test Answers – Model 2
- California CDL Air Brakes Practice Test Answers – Model 3
- California CDL Air Brakes Practice Test Answers – Model 4
- California CDL Air Brakes Practice Test Answers – Model 5
- California CDL Air Brakes Practice Test Answers – Model 6
- California CDL Air Brakes Practice Test Answers – Model 7
- California CDL Air Brakes Practice Test Answers – Model 8
- About California Air Brakes Test
California CDL Air Brakes Practice Test Answers – 330+ Solved
All California CDL Air Brakes Practice test questions and answers to different topics below are checked twice before publishing them to you.
You can select any topic of your wish and get the answers for FREE:
California CDL Air Brakes Practice Test Answers – Model 1
Q. After every working day
Ans: 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?
Q. Why drain water from the compressed air tanks?
Ans: Water can freeze in cold weather and cause brake failure.
Q. The air brake system for a straight truck or bus should not leak at a rate of more than __ psi per minute with the engine off and the brakes released.
Ans: 2
Q. To make an emergency stop with air brakes, using the stab braking method, you should:
Ans: Press on the brake pedal as hard as you can, release the brakes when the wheels locked, put on the brakes again when the wheels start rolling.
Q. You should know that your brakes are fading when:
Ans: You have to apply the brake pedal harder to control speed on a downgrade.
Q. If the air compressor should develop a leak, what keeps the air in the tanks?
Ans: The one way check valve.
Q. To check the brake slack on S-cam brakes you should park on:
Ans: Park on level ground, chock the wheels, and release the parking brakes.
Q. The application pressure gauge shows how much pressure you have:
Ans: When you are applying to the brakes.
Q. The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below __ psi.
Ans: 20
Q. The safety valve is set to automatically reduce pressure at __ psi.
Ans: 150
Q. Your truck has a dual air system and one system loses its pressure. What will happen?
Ans: Either the front or back brake will not be fully operational.
Q. If your truck or bus has dual parking control valves, you can use pressure from a separate tank to:
Ans: Release the spring emergency/parking brakes to move a short distance.
Q. If your truck has a properly functioning dual air brake system and minimum size air tanks. The air pressure should build from 85 to 100 psi within _ seconds?
Ans: 45
Q. During normal driving, spring brakes are usually held back by:
Ans: Air pressure
Q. The air compressor stops pumping air at what psi?
Ans: 125
Q. The driver must be able to see a warning before pressure in the service air tanks falls below __ psi.
Ans: 55
Q. Excessive use of the service brakes results in overheating which can lead to:
Ans: Expansion of the brake drums.
Q. The most common type of foundation brake found on heavy vehicles is the:
Ans: S-cam drum
Q. If you must make an emergency stop, brake so you:
Ans: Can steer and your vehicle stays in a straight line.
Q. The braking power of the spring brakes:
Ans: Depends on the service brakes being in adjustment.
Q. The air brake lag distance at 55 mph on dry pavement adds about _ feet.
Ans: 32
Q. Total stopping distance for air brakes is longer than that for hydraulic brakes due to _ distance.
Ans: Brake lag
Q. It is accepted that too much heat caused by using your brakes too often can also cause:
Ans: Brake fade or failure
Q. Repeatedly pressing and releasing (fanning) the brake pedal may result in:
Ans: The loss of brake air pressure
Q. The brake system that applies and releases the brakes when the driver uses the brake pedal is the __ brake system.
Ans: Service
Q. A slack adjuster’s free play needs to be adjusted if it is more than about how many inches when you pull hard on it?
Ans: 1 inch
Q. The brake pedal in an air brake system:
Ans: Controls the air pressure applied to put in the brakes.
Q. Under normal conditions in order to engage the parking brakes the driver must first:
Ans: Let the air out of the spring brakes.
Q. Which of these is NOT a proper time to apply the parking brakes?
Ans: If your brakes are very hot.
Q. What is the first thing you should do when a low air pressure warning comes on:
Ans: Stop and safety park as soon as possible.
California CDL Air Brakes Practice Test Answers – Model 2
Q. The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot peak away, like:
Ans: Spring Pressure
Q. When you apply the brakes, the brake shoes/linings are pressed against the:
Ans: Brake drum.
Q. If the air pressure is not building up fast enough within the correct amount of time:
Ans: Your air pressure may drop too low during driving.
Q. The proper method of braking when going down a long and/or steep grade after selecting the proper gear is to brake until your speed is about _ miles per hour below your “safe” speed, then release your brakes.
Ans: 5
Q. In ideal conditions, a truck or bus with an air brake going 55 mph would require a stopping distance of how many feet?
Ans: More than 300 feet
Q. It is not safe for a vehicle that has brake drums with cracks that are longer than _ of the width of the friction area.
Ans: 1/2
Q. Why must air tanks be drained?
Ans: To drain moisture and oil out of the tank.
Q. Is it possible to have an air leak on one system which will not affect the other?
Ans: Yes
Q. Both systems run off of the same air compressor, so it one air compressor malfunctions you will not be able to build or maintain pressure in either system.
Ans: True
Q. All vehicles with air brakes must have a low-pressure warning signal.
Ans: True
Q. What are spring brakes?
Ans: If the air brakes leak down, springs press the brakes on to stop the vehicle.
Q. Front wheel brakes are good under all conditions.
Ans: True
Q. When you apply your brakes, the air brake system works with an electric switch, by air pressure, to turn on the brake lights.
Ans: True
Q. What do air brakes use to make the brakes work?
Ans: Compressed air
Q. The service brake applies and releases:
Ans: The brake pedal when you use the brake pedal during normal driving.
Q. The parking brake applies and releases:
Ans: The parking brakes when you use the parking brake control.
Q. The emergency brake system:
Ans: Uses parts of the service and parking brake system to stop the vehicle in the event of a brake system failure.
Q. The governor controls when the air compressor will pump into the air storage tanks.
Ans: True
Q. When air pressure falls to the minimum pressure allowed in the system, the governor prevents more air from escaping the air tanks.
Ans: False
Q. The storage tanks are used to hold compressed air.
Ans: True
Q. When you put the brakes on by pushing down on the brake pedal:
Ans: Air pressure is applied to the brake pads.
Q. The S-cam forces the brake shoes away from one another and presses them against the inside of the brake drum. It is called the S-cam because:
Ans: It is shaped like the letter “S”.
Q. What is a dual air brake system?
Ans: A two brake system, one operates the front brakes and one operates the back brakes.
Q. What are the slack adjusters?
Ans: It is an adjusting nut on the backside of the brake drum used for adjusting the brakes.
Q. How can you check the slack adjuster?
Ans: Park on level ground, turn off parking brakes, pull hard on each slack adjuster. It shouldn’t move more than one inch.
Q. How can you test the low pressure warning signal?
Ans: Shut off the engine with enough air pressure, turn on the electrical power and step on and off the brake pedal until the low air pressure warning signal comes on.
Q. What are the maximum leakage rates?
Ans: Less than 2 psi in one minute for single vehicles and less than 3 psi in one minute for combination vehicles.
Q. When is it OK to leave your truck unattended without applying parking brakes or chocking the wheels?
Ans: Never
Q. If you are away from your vehicle for only a short time you don’t need to use the parking brake.
Ans: False
Q. If you do not have automatic tank drains, how often should you drain the oil and water from the bottom of compressed air storage tanks?
Ans: At the end of each day of driving.
California CDL Air Brakes Practice Test Answers – Model 3
Q. The use of brakes on a long steep downgrade is only a supplement to the braking effect of the engine.
Ans: True
Q. What factors can cause brakes to fade or fail?
Ans: Overheating, low air pressure, and not relying on the engine braking effect.
Q. Why should you be in the proper gear before starting down a hill?
Ans: So you only have to apply the brake just hard enough to feel a definite slowdown.
Q. If oil and water collects in the air tanks what can happen to the brakes?
Ans: The brakes could fail
Q. What is the purpose of an alcohol evaporator?
Ans: To reduce the risk of ice in the brake valves and other parts in cold weather.
Q. What is another name for controlled braking?
Ans: Squeeze braking
Q. The brake chamber fills with air pushing the rod out which moves the _______ ______________, which twists the _________ _______.
Ans: Slack adjuster and brake camshaft.
Q. If your vehicle has an alcohol evaporator you should check and fill the alcohol level everyday during cold weather.
Ans: True
Q. To test the air service brakes you should:
Ans: Brake firmly while slowly moving forward.
Q. The driver must be able to see a low-pressure warning which comes on before pressure in the service air tank falls below:
Ans: 60 psi
Q. Converter dollies built on or after March 1, 1998 are required to have anti-lock brakes. These dollies will have:
Ans: A yellow malfunction lamp on the left side of the dolly.
Q. Which of these is the most important thing to remember about emergency braking?
Ans: If the wheels are skidding, you cannot control the vehicle.
Q. Controlled braking:
Ans: Is used to keep a vehicle in a straight line when braking.
Q. To correct a drive-wheel braking skid, you should:
Ans: Stop braking, turn quickly, and countersteer.
Q. How do you test the hydraulic brakes for leaks?
Ans: Pump the brake pedal three times, then apply firm pressure to the pedal and hold for five seconds. The pedal should not move.
Q. Modern air brake systems are three different systems combined together. They are the service, parking, and the __ brakes.
Ans: Emergency
Q. The air supply pressure gauge shows how much pressure:
Ans: Is in the air tanks
Q. The parking or emergency brakes of trucks or buses can legally be held on by ____ pressure.
Ans: Spring
Q. Air brake equipped vehicles have:
Ans: An air supply pressure gauge.
Q. The stop light switch:
Ans: Turns on the brake lights to warn drivers behind you.
Q. With air brake vehicles, the parking brakes should be used:
Ans: Whenever you leave the vehicle unattended
Q. The use of air brakes on a downgrade is only a supplement to the:
Ans: Braking effect of the engine.
Q. Excessive heat in the brakes can cause the:
Ans: Brakes to fade or fail
Q. You are on a steep down grade and have reached your safe speed of 40 mph. You would apply the service brakes until your speed drops to ______ mph.
Ans: 35
Q. If your bus or truck has dual parking control valves, you can use pressure from a separate tank to:
Ans: Release the spring emergency/parking brakes to move a short distance.
Q. The modulating control valve allows you to control the:
Ans: Spring brakes
Q. Some air brake systems have an alcohol evaporator. What may happen if you don’t keep the unit filled with alcohol?
Ans: Ice may form in the air storage tanks and cause the brakes to fail.
Q. Before driving a truck or bus with a dual air brake system, the pressure in each air brake system should be at least _ psi.
Ans: 100
Q. How should you check that the spring brakes come on when the air pressure in the system drops below a certain level?
Ans: Park on level ground, chock the wheels, release the parking brake when you have enough air pressure, shut the engine off, and repeatedly press and release the brake pedal.
Q. For air brake systems in good condition, the air compressor should start pumping at about _ psi.
Ans: 100
California CDL Air Brakes Practice Test Answers – Model 4
Q. In air brake vehicles, the parking brake should be used:
Ans: Any time the vehicle is parked.
Q. The most important thing to do when a low air pressure warning comes on is:
Ans: Stop and safely park as soon as possible.
Q. If your vehicle has an alcohol evaporator, every day during cold weather you should:
Ans: Check and fill the alcohol level.
Q. Your bus or truck has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?
Ans: Stop and safely park. Continue only after the system is fixed.
Q. It is not safe to drive a vehicle that has brake drums(or discs) with cracks or that are thinner than the manufacturer’s specifications, generally this will be _ an inch.
Ans: 1/2
Q. Emergency controlled braking is when you:
Ans: Apply the brakes as hard as you can without locking the wheels.
Q. When performing you air brake leak down test your engine should be turned off.
Ans: True
Q. Before driving a truck or bus with a dual air brake system, the pressure in each system should be at least
Ans: 100 psi
Q. All air brake-equipped vehicles have
Ans: A supply pressure gauge
Q. When the brakes are applied the brake shoes (or linings) are pressed against the
Ans: Brake drum or disc
Q. How should you check that your service brakes are working properly?
Ans: Park on level ground, wait for normal air pressure, release the parking brake, move the truck forward slowly (about 5 mph) and apply the brakes firmly using the brake pedal
Q. To test air service brakes, you should
Ans: Brake firmly when slowly moving forwards
Q. The modulating control valve allows you to control the
Ans: Spring brakes
Q. When is it okay to leave your truck unattended without applying the parking brake or chocking the wheels?
Ans: Never
Q. The driver must be able to see a warning before air pressure in the service air tanks falls below
Ans: 60 psi
Q. An air brake system is fully charged at
Ans: 125 psi
Q. If the spring brakes are on, when should
Ans: Never
Q. How should you check that the spring brakes come on when air pressure in the system drops below a certain level?
Ans: Park on level ground, chock the wheels, engage the park brake when you have the correct amount of air pressure to do so, and shut the engine off
Q. The brake pedal in an air brake system
Ans: Controls the air pressure applied to put on the brakes
Q. If the spring brakes are on, when should you push the brake pedal?
Ans: Never
Q. Emergency controlled braking is when you
Ans: Apply the brakes as hard as you can without locking the wheels
Q. If your truck’s air compressor has its own oil supply, when should you first check the oil level?
Ans: Before driving
Q. The parking or emergency brakes on a heavy vehicle can only be held in position by something that cannot lead away, like
Ans: Spring pressure
Q. If your truck has a dual air system and one of the systems is low on pressure
Ans: Either the front or rear brakes will not be fully operational
Q. The stop light switch
Ans: Turns on the brake lights to ward drivers behind you
Q. Modern air brake systems combine three different systems. They are the service, parking, and the
Ans: Emergency brakes
Q. The proper method of braking when going down long and/or steep grades after selecting the proper gear is to brake until your speed is about
Ans: 5 miles per hour below your “safe” speed, then release your brakes
Q. You should know that your brakes are fading when
Ans: You have to push down harder on the brake pedal to control your speed on a downgrade
Q. The braking power of the spring brakes
Ans: Depends on the service brakes being in adjustment
Q. The safety valve is set to automatically reduce pressure at
Ans: 150 psi
California CDL Air Brakes Practice Test Answers – Model 5
Q. During normal driving, spring brakes are usually held back by
Ans: Air pressure
Q. Why drain water from compressed air tanks?
Ans: Water can freeze in cold weather and cause brake failure
Q. A slack adjuster probably needs to be adjusted if it moves than about
Ans: 1 inch when you pull hard on it
Q. To check the free play of manual slack adjusters on S-cam brakes, you should park on
Ans: Level ground, chock the wheels, and turn off the parking brakes
Q. The use of air brakes on a long and/or steep downgrade under normal conditions is only a supplement to
Ans: The braking effect of the engine
Q. Emergency stab braking is when you
Ans: Brake as hard as you can, release the brakes when the wheels lock, put on the brakes again when the wheels start rolling
Q. Air braking takes more time than hydraulic braking because
Ans: Air takes more time to flow through the lines than hydraulic fluid
Q. The S-cam
Ans: Forces the brake shoes against the inside of the brake drum
Q. Total stopping distance for air brakes is longer than that for hydraulic brakes due to
Ans: Brake lag distance
Q. Of the choices below, the first thing to do when a low air pressure warning comes on is
Ans: Stop and safely park as soon as possible
Q. In air brake vehicles, the parking brakes should be used
Ans: Any time the vehicle is parked
Q. Under normal conditions, in order to engage the parking brakes the driver must first
Ans: Let the air out of the air system
Q. How should you check that the spring brakes come one when air pressure in the system drops below a certain level?
Ans: Park on level ground, chock the wheels, engage the park brake when you have the correct amount of air pressure to do so, and shut the engine off
Q. A slack adjuster probably needs to be adjusted if it moves more than about
Ans: 1 inch when you pull hard on it
Q. The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot lead away, like
Ans: Spring pressure
Q. Some air brakes systems have an alcohol evaporator. What may happen if you don’t keep the unit filled with alcohol?
Ans: Ice may form in the air storage tanks and cause the brakes to fail
Q. The application pressure gauge shows how much air pressure you
Ans: Are applying to the brakes
Q. To test service brakes, you should
Ans: Brake firmly when slowly moving forwards
Q. If your vehicle has an alcohol evaporator, it is there to
Reduce the risk of ice in air brake valves in cold weather
Q. The air loss rate for a straight truck or bus with the engine off and the brakes on should not be more than
Ans: 3 psi in one minute
Q. A supply pressure gauge tells you how much air is in the
Ans: Air tanks
Q. If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build from 85 psi to 100 psi within
Ans: 45 seconds
Q. The air compressor governor controls
Ans: When air is pumped into the air tanks
Q. If you must make an emergency stop, brake so you
Ans: Can steer and your vehicle stays in a straight line
Q. For a straight truck or bus air brake system, the loss rate should be less than
Ans: 2 psi per minute with the engine off and the brakes released
Q. The brake system that applies and releases the brakes when the driver uses the brake pedal is the
Ans: Service brake system
Q. The most important thing to do when a low air pressure warning comes on is
Ans: Stop and safely park as soon as possible
Q. Excessive use of the service brakes results in overheating, which can lead to
Ans: Expansion of the brake drums
Q.Air Brakes
Ans: Air brakes are a type of braking system usually seen on heavy vehicles that use compressed air to brake the wheels.
Q. Air loss in a straight truck or bus should not be more than how much PSI with the engine off and the brakes on?
Ans: 3 PSI in one minute
California CDL Air Brakes Practice Test Answers – Model 6
Q. All vehicles with air brakes must have what signal?
Ans: Low air pressure warning signal
Q. It is accepted that too much heat caused by using your brakes too often can also cause what?
Ans: brake to fade or fail
Q. When is it ok to leave your truck unattended without applying the parking brakes and choking the wheels?
Ans: Never
Q. You should know that your brakes are fading when you have to do what?
Ans: push harder on the brake pedal to control your speed on a downgrade
Q. The safety valve discharges automatically at what pressure?
Ans: 150
Q. What is a dual airbrake system?
Ans:
– one operates front brakes
– one operates back brakes
Q. If air pressure is not built up within the correct amount of time, then what will happen?
Ans: air pressure may drop to a low point while driving, requiring an emergency stop
Q. How often should you drain air tanks?
Ans: Daily
Q. A slack adjusters free play needs to be adjusted if it is more than about how many inches when you pull hard on it?
Ans: 1 inch
Q. In ideal conditions, a truck or bus with an air brake going at 55 mph would require a stopping distance of how many feet?
Ans: more than 300 feet
Q. If air pressure is not built up within the correct amount of time, then what will happen to the air pressure?
Ans:
– drop to a low point while driving
– requiring an emergency stop
Q. It is accepted that too much heat caused by using your brakes too often can also cause what?
Ans: Brake to fade or fail
Q. What does the governor control?
Ans: when air compressor will pump into air storage tanks
Q. To make an emergency stop with air brakes, using the stab braking method, you should do what?
Ans:
– Brake as hard as you can
– get off brakes when wheels lock
– get back on brakes when wheels start rolling
Q. The driver must be able to see a low air pressure warning which comes on before pressure in the service air tanks falls below what PSI?
Ans: 60
Q. The use of brakes on a long steep downgrade is only a supplement to the braking effect of the engine
Ans: True
Q. The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below what PSI?
Ans: 60
Q. What do air brakes use to make the brakes work?
Ans: Compressed Air
Q. What can legally hold a parking or emergency brake in position for a truck, truck tractor, or bus?
Ans: Spring Pressure
Q. When you put on the brakes by pushing down the brake pedal, what happens?
Ans: Air pressure is applied to the brake pads
Q. Air loss in a straight truck or bus should not be more than what with the engine off and the brakes on?
Ans: 3 PSI in one Minute
Q. What does the Emergency Brake System do?
Ans: Uses part of the service and parking brake system to stop the vehicle in the event of a brake system failure
Q. The most common type of foundation brake found on heavy vehicles is what?
Ans: S-cam drum
Q. Modern air brake systems combines what 3 different systems?
Ans:
– Service Brake
– Parking Brake
– Emergency Brake
Q. Excessive use of the service brakes result in overheating which can lead to what?
Ans: Expansion of the brake drums
Q. Your truck or bus has a dual air brake system. If a low air pressure warning comes on only for 1 system, what should you do
Ans:
– Bring vehicle to complete stop right away and safely park
– Continue only after system is fixed
Q. The use of brakes on a long and steep downgrade under normal conditions is only a supplement to what?
Ans: braking effect of the engine
Q. When you put your brakes on, the air brakes system works with an electric switch by air pressure to turn on the brake lights
Ans: True
Q. If the air compressor should develop a leak, what keeps the air in the tanks?
Ans: One-way check valve
California CDL Air Brakes Practice Test Answers – Model 7
Q. Why do air braking systems take longer than hydraulic braking systems?
Ans: air takes more time to flow through the lines than hydraulic fluid
Q. What are spring brakes?
Ans: If air brakes leak down, springs press the brakes on to stop the vehicle
Q. The service brake applies and releases the brake when the driver does what?
Ans: uses the brake pedal during normal driving
Q. A straight truck or bus air brake system should not leak at the rate of more than what PSI per minute with the engine off and the brakes released.
Ans: 2 PSI
Q. What can you check to see if the spring brakes come on automatically?
Ans:
– Step on and off the brake, with engine off
– parking brake knob should pop out when air pressure falls between 20-40 psi
Q. It is not safe to drive a vehicle that has brake drums with cracks that are longer than _ width of the friction area?
Ans: 1/2
Q. What is another name of controlled braking?
Ans: Squeeze Braking
Q. What is a supply pressure gauge used for?
Ans: Tells how much air is in the tank
Q. An air brake system is fully charged at what PSI?
Ans: 125
Q. The braking power of the spring brakes depends on what?
Ans: service brakes being in adjustment
Q. The S-cam forces the brake shoes away from each other and presses them against the inside of the brake drum. Why is it called the S-Cam?
Ans: Shaped like an S
Q. Under normal conditions, in order to engage the parking brakes, the driver needs to do what?
Ans: let air out of air brake system
Q. During normal driving, Spring brakes are usually held back by what?
Ans: air pressure
Q. If you are driving down to the steep downgrade and you have reached the speed of 40 mph, you would apply the service brake until your speed dropped to below how many mph?
Ans: 35
Q. Total stopping distance for air brakes is longer than that for hydraulic brakes due to what?
Ans: Brake Lag distance
Q. If oil and water collect in the air tanks, what can happen to the brakes?
Ans: They could fail
Q. The safety valve discharges automatically at the pressure of what?
Ans: 150
Q. How can you test the low pressure warning signal?
Ans:
– Shut off the engine with enough air pressure
– turn on electrical power
– step on and off brake pedal until the low air pressure warning signal comes on
Q. Parking or emergency brakes of trucks and buses can legally be held on by what pressure?
Ans: Spring
Q. What are the slack adjusters?
Ans: adjusting nut on the backside of the brake drum used for adjusting the brakes
Q. When air brakes are applied, the brake shoes will press against what?
Ans: Brake drum or disc
Q. Your truck has a dual air system and one of the system loses its pressure. What will happen?
Ans: Either the front or back brake will not be fully operational
Q. Air brake-equipped vehicles must have a what?
Ans: Supply pressure gauge
Q. The air compressor stops pumping air at what PSI?
Ans: 125
Q. What is the most important thing to do if the low air pressure warning comes on?
Ans: Stop and safely park as soon as possible
Q. What are the air storage tanks used for?
Ans: hold compressed air
Q. How can you check the slack adjusters?
Ans:
– Park on Level ground
– turn off parking brakes
– pull hard on each slack adjuster
– shouldn’t move more than 1 inch
Q. If you are away from your truck for only a short period of time, you don’t have to use your parking brake
Ans: False
Q. Some air brake systems have an alcohol evaporator. What may happen if you do not keep the proper level of alcohol?
Ans: Ice may form in the air storage tank and cause brake failure
Q. If the spring brakes are on, when should you push the brake pedal?
Ans: Never
California CDL Air Brakes Practice Test Answers – Model 8
Q. Air loss rate in a straight truck or bus with the engine off and brakes on should not be more than how much PSI
Ans: 3 PSI in one minute
Q. The safety valve reduces pressure at what PSI?
Ans: 150
Q. The air brake lag distance at 55 mph on dry pavement adds about how many feet?
Ans: 32
Q. What are the maximum leakage rates?
Ans: less than 2 PSI in one minute for single vehicles & less than 3 psi for combination vehicles.
Q. The application pressure gauge shows how much pressure you are what?
Ans: applying to the brakes
Q. IF your truck or bus had dual parking control valves, you can use pressure from a separate tank to release what?
Ans: spring emergency/parking brakes to move short distance
Q. What does the S-Cam do?
Ans: Forces the brake shoes against the inside of the brake drum
Q. Repeatedly partially releasing and pressing the brake pedal may result in what?
Ans: loss of brake air pressure
Q. The parking or emergency brake on a heavy vehicle can only be held in position by something that cannot leak away, like what?
Ans: Spring Pressure
Q. To check the free play of manual slack adjustors on S-cam brakes, you should what?
Ans:
– Park on level ground
– chock the tires
– release parking brakes
Q. Why drain water from the compressed air tanks?
Ans: water may freeze in cold weather and cause brake failure
Q. If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build up from 85 PSI to 100 PSI within how many seconds?
Ans: 45
Q. If you must make an emergency stop, you should brake so you can what?
Ans: steer and so your vehicle stays in a straight line
Q. The brake pedal in the air brake system controls what?
Ans: air pressure applied to put on the brakes
Q. When is not a proper time to apply the parking brakes?
Ans:
– to brake vehicle very hard
– coming down the steep grade
Q. Why must air tanks be drained?
Ans: to drain moisture and oil out of the tank
Q. What factors can cause brakes to fade or fail
Ans:
– Overheating
– low air pressure
– not relying on engine braking system
Q. All air brake equipped vehicles have what?
Ans: supply pressure gauge
Q. The parking brake applies and releases when?
Ans: the parking brakes when you use the parking brake control
Q. The brake system that applies and releases the brakes when the driver uses the brake pedal is what brake system?
Ans: service
Q. Should you ever leave your vehicle unattended without applying the brakes or choking the tires?
Ans: No
Q. A slack adjusters free play needs to be adjusted if it is more than how many inches when you pull hard on it?
Ans: 1 inch
Q. Why should you be in the proper gear before starting down a hill?
Ans: so you only have to apply the brake just hard enough to feel a definite slowdown
Q. you should know that your brakes are fading when you have to what?
Ans: push harder on the brake pedal to control your speed on a downgrade
Q. The proper use of brakes when going down a long steep grade after selecting a proper gear is to brake until your speed is _ mph below the posted speed for your safety and release your brake?
Ans: 5 mph
Q. When is the safety valve automatically set?
Ans: when pressure is 150
Q. To make an emergency stop with air brakes, using the stab braking method, you should
Ans:
– Brake as hard as you can
– Get off brakes when wheels lock
– Get back on brakes when wheels start rolling again
Q. Front Wheel brakes are good under all conditions
Ans: True
>> Explore more CDL Answers Here <<
About California Air Brakes Test
California CDL holders must have a thorough understanding of how air brakes work in order to operate a vehicle equipped with them. The California DMV requires all applicants for a CDL to take and pass a written air brakes test.
If you’re planning to drive a commercial vehicle in California, it’s important to understand the state’s regulations surrounding air brakes. This guide will provide you with the information you need to ensure you’re in compliance with the law.
In California, all commercial vehicles that weigh more than 26,000 pounds must be equipped with air brakes. This includes both trucks and buses.
Air brakes are required on all commercial vehicles because they provide more stopping power than traditional hydraulic brakes. They’re especially important in California, where the hilly terrain can make it difficult to stop a heavy vehicle.
Read more here: https://www.dmv.ca.gov/portal/handbook/commercial-driver-handbook/section-5-air-brakes/
Hope you got access to California CDL Air Brakes Practice Test Answers by following to above what we shared. Share with other students if you find it helpful.