Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Manually operated air tank drains must be opened daily to remove this build-up.

Are necessary for the proper function of the air brake system.

The stab braking method for emergency stops involves fully applying the brakes until they lock up. The brakes are then released until the wheels start rolling, and then the process is repeated.

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.

When driving a vehicle with air brakes, if the low air pressure warning light comes on, it is important for you to stop and safely park your vehicle as soon as possible. There may be a leak in the system. Controlled braking will remain possible only as long as there is enough air left in the tanks.

Braking will only be possible if there is still enough air in the tanks.

You can apply the brakes 14 times before the air in the system runs out.

You should continue to drive normally and check the brake system when it is convenient.

You should stay at least 100 feet away from other vehicles.

The stab braking method for emergency stops involves fully applying the brakes until they lock up. The brakes are then released until the wheels start rolling, then the process is repeated.

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 keep the wheels rolling.

Fully apply the brakes, let the wheels lock up, and hold the brake pedal down, keeping the wheels locked until the vehicle stops.

Air Brakes Endorsement Test | South Carolina 2025 #1

Train for FREE online with our South Carolina CDL air brake test. The official exam test consists of several obligatory parts, with all of them checking your knowledge of different blocks of road rules. If you need to obtain a SC Class A/Class B driver license in 2025, practice as much as possible. Free sample tests published on our website will help you check and improve your knowledge and boost your grades. Please bear in mind that the requirements for CDL may vary from state to state.

Number of Question 25

Passing Score 20

Number of Tests 20

Air Brakes Endorsement Test | South Carolina 2025 #1

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

2 . To use the stab braking method, you should:

3 . If the low pressure warning light comes on while you are driving:

4 . To use the stab braking method in an emergency situation, you should:

5 . What kind of force must emergency brakes use?

6 . 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.

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