Air Brakes Endorsement Test | Iowa 2024 #2

Train for FREE online with our Iowa 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 IA Class A/Class B driver license in 2024, 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

1 . Anti-Lock Braking Systems (ABS):

Reduce a vehicle's normal braking capacity.

Are in addition to other braking systems and do not reduce a vehicle's braking power.

Are not effective on larger vehicles.

If equipped, ABS is in addition to a vehicle's normal braking system and does not increase or decrease the braking power of any other system. ABS only activates when a vehicle's wheels are about to lock.

2 . If the low air pressure warning signal comes on, you should:

Continue driving, but have the brakes repaired within a week.

Pull over and inspect the brakes.

Phone a mechanic while driving.

If the low air pressure warning signal comes on while you are driving a vehicle with air brakes, you should immediately bring the vehicle to a safe stop while you are still able to control the brakes. Inspect and repair the brakes as soon as possible.

3 . What is removed when an air tank is drained?

Water and oil

Ammonia

Liquid cleaners

In an air brake system, air tanks have drains to remove accumulations of water and compressor oil. Allowing water and oil to accumulate in the system could cause damage to the brakes.

4 . Lights that indicate that anti-lock brakes are not working are:

Gray.

Blue.

Yellow.

Vehicles equipped with Anti-Lock Braking Systems (ABS) have yellow malfunction lights to indicate issues in the braking system.

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

Hoses

An air compressor

Air tanks

Both systems in a dual air brake systems share a single air compressor. If the air compressor is damaged, neither system will be able to operate properly.

6 . ____ make up the emergency brake system.

Only parts of the parking brake system

Only parts of the service brake system

Parts of the parking and service brake systems

In an air brake system, there are three different braking systems: a service brake system, a parking brake system, and an emergency brake system. The emergency brake system uses parts of both the parking and service brake systems.

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2024 Iowa | Frequently Asked Questions

To secure a CDL Doubles/Triples endorsement in Iowa, you must first possess a valid Commercial Driver's License (CDL). Then, you need to pass the Doubles and Triples Endorsement Knowledge Test. This test covers the specifics of driving double and triple trailers, coupling and uncoupling, and inspecting doubles and triples. Remember, practice makes perfect.

To obtain a CDL Doubles/Triples license, you initially need a Commercial Driver's License (CDL). Then, you must pass the Doubles/Triples Endorsement Knowledge Test. The test covers topics like handling, coupling & uncoupling, and inspecting double and triple trailers. Studying the state's CDL manual and taking practice tests can help ensure success.

While Iowa doesn't specifically require specialized training to obtain a CDL Doubles/Triples endorsement, it's highly recommended. The endorsement requires passing a knowledge test on handling, inspecting, and coupling/uncoupling double and triple trailers. Studying the state's CDL manual and gaining practical experience through training programs can significantly improve your chances of passing the test.

Yes, to obtain a CDL Doubles/Triples endorsement, you are required to pass the Doubles/Triples endorsement knowledge test. This exam covers specific topics related to handling double and triple trailers, including coupling and uncoupling, inspecting doubles and triples, and pulling double/triple trailers. The test does not include a skills or driving test.

The CDL Doubles/Triples endorsement test is a written knowledge test, not a skills test, so you won't perform any driving maneuvers. The test covers information on handling, inspecting, and coupling/uncoupling double and triple trailers. It's important to have a good understanding of these areas to pass the written test. Practical skills are typically developed during on-the-job training after receiving the endorsement.

No, it's not permissible to operate double or triple trailers without a valid CDL Doubles/Triples endorsement in Iowa. This endorsement is required by federal and state law for any driver who intends to operate a vehicle towing two or three trailers. Driving without the proper endorsement can result in penalties, including fines and suspension of your commercial driving privileges.

You can add the CDL Doubles/Triples endorsement to your existing Commercial Driver's License. You don't need to initiate a new application for a CDL. However, you will need to pass the Doubles/Triples written knowledge test and pay any required fees to add the endorsement to your current CDL.

Yes, there are limitations for drivers with a CDL Doubles/Triples endorsement. One major constraint is the Gross Combination Weight Rating (GCWR) of 26,001 pounds or more, provided the GVWR of the vehicle(s) being towed is more than 10,000 pounds. Additionally, drivers must adhere to specific safety regulations related to coupling and uncoupling, inspecting, and driving double/triple trailers.

In Iowa, the maximum length for a double trailer is 81.5 feet. For triple trailers, it's 100 feet. The maximum weight for any vehicle or combination is 80,000 pounds gross weight depending on axle and bridge formula. However, specific weight limits can also be determined by the Federal Bridge Gross Weight Formula. Always check local and state laws for specific restrictions.

Yes, there are specific safety regulations for driving double/triple trailers. Drivers must adhere to guidelines concerning coupling and uncoupling, inspecting the trailers, and maintaining safe following distances. Other regulations include not driving in the left-most lane on interstates, obeying speed limits, and securing cargo properly. These regulations aim to ensure the safety of the driver and other road users.