Air Brakes #1
Air Brakes Endorsement Test | Idaho 2025 #1 Page 2 of 4
Train for FREE online with our Idaho 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 ID 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.
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7 . When operating a vehicle with a dual air brake system, the driver should:
Before driving a vehicle with a dual air brake system, allow time for the air compressor to build up a minimum of 100 psi pressure in both the primary and secondary systems. Watch the air pressure gauges to monitor the pressure levels.
8 . What color light indicates a vehicle's ABS is not working?
On vehicles with Anti-Lock Braking Systems (ABS), yellow malfunction lamps alert the driver to ABS malfunction.
9 . What is brake lag?
Because air takes time to flow through the air lines to the brakes, air brakes cannot begin working instantly. There is often a brake lag of at least one-half of a second between the moment the brake pedal is pressed and the moment the brakes begin to work.
10 . The rods in S-cam brakes move the slack adjusters when air pressure is added to the brake chambers. This air pressure is added to the chambers when the driver:
When pressing the brake pedal in a vehicle with S-cam brakes, air will enter the brake chambers. The added air pressure will push out the rods and move slack adjusters, twisting the brake camshafts.
11 . An alcohol evaporator is especially important:
Some air brake systems contain an alcohol evaporator. This evaporator introduces alcohol into the system to help prevent ice from forming in cold weather.
12 . Air tank drains should:
In an air brake system, air tank drains are used to remove water and compressor oil from the air tanks. When operating a drain, be sure to drain the tank completely.
2025 Idaho | Frequently Asked Questions
A CDL Class B license in Idaho allows the holder to operate single vehicles with a gross vehicle weight rating (GVWR) of 26,001 pounds or more, or a towed vehicle not exceeding 10,000 pounds GVWR. This includes straight trucks, large buses, segmented buses, and dump trucks with small trailers. A special endorsement may be needed for certain vehicles.
A Class B CDL license in Idaho allows the holder to operate single vehicles with a gross vehicle weight rating (GVWR) of 26,001 pounds or more, or tow a vehicle not exceeding 10,000 pounds GVWR. This includes straight trucks, large buses, segmented buses, farm labor vehicles, and dump trucks with small trailers. Special endorsements may be required for certain vehicles.
To acquire a Class B CDL license in Idaho, the applicant must be at least 18 years old for intrastate transport and 21 for interstate transport. They must pass a vision test, obtain a Medical Examiner's Certificate, pass a General Knowledge test, and a skills test which includes pre-trip inspection, basic controls, and on-road driving. Prior to testing, applicants need a Commercial Learner's Permit (CLP).
In Idaho, you must be at least 18 years old to qualify for a Class B CDL license for intrastate transport (within Idaho only). However, if you intend to drive interstate (across state lines), you must be at least 21 years old. These age requirements are set by the Federal Motor Carrier Safety Administration.
Specific endorsements aren't necessary for a Class B CDL license in Idaho, but they can broaden the range of vehicles you can operate and materials you can transport. These endorsements include passenger, school bus, tanker, hazardous materials (HazMat), and double/triple trailers. To get these endorsements, you must pass additional knowledge and skills tests.
The Class B CDL skills assessment in Idaho includes a pre-trip vehicle inspection, a basic vehicle control test, and an on-road driving test. You'll demonstrate your ability to inspect your vehicle, control its operation, and drive it safely in various road and traffic conditions. The specific maneuvers and operations you'll perform depend on the type of vehicle you're testing in.
Yes, Class B CDL license holders in Idaho are limited to operating vehicles with a gross vehicle weight rating (GVWR) of 26,001 lbs or more, or a vehicle towing another vehicle not exceeding 10,000 lbs GVWR. They cannot drive Class A vehicles (tractor-trailers) without the appropriate license. Also, without specific endorsements, they cannot transport hazardous materials or more than 15 passengers.
In Idaho, the written CDL test is primarily offered in English. However, some locations may offer the test in Spanish. It's important to note that all CDL applicants must pass an English proficiency test, as federal regulations require drivers to read and speak English to ensure road safety. Always check with your local DMV for available language options.
Yes, you can request test accommodations for the Class B CDL written exam in Idaho due to disability. The Idaho Transportation Department adheres to the Americans with Disabilities Act (ADA) and provides reasonable accommodations. However, you must provide documentation to verify your disability. Contact your local DMV office to discuss your specific needs and to ensure the right accommodations are made.
If you fail the Class B CDL written test in Idaho, you can retake it. However, you must wait at least three days before you can try again. Keep in mind that each attempt may require an additional fee. It's recommended to study thoroughly using the Idaho CDL manual and online practice tests to increase your chances of passing on the next attempt.