Air Brakes #1
Air Brakes Endorsement Test | Iowa 2025 #1 Page 3 of 4
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 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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13 . What kind of brakes do most newer heavy-duty trucks use?
Most newer heavy-duty vehicles use dual air brake systems. A dual air brake system has two separate air brake systems which use a single set of brake controls.
14 . Do not operate a vehicle if any brake drums have cracks that are larger than ____ of the width of the friction area.
Before beginning a trip, it is important to check the brake drums during your walk-around inspection. It is unsafe to drive if any brake drum has a crack more than one half of the width of the friction area.
15 . While operating on a downgrade, you should brake until you reach a speed that is:
While driving downhill, you should hold down the brake pedal until your vehicle reaches a speed 5 mph below your safe speed, then release the brake pedal. Repeat this process.
16 . Brake fade is a result of:
If brakes are overused, they can become too hot. This overheating causes them to fade, making them less effective at slowing the vehicle.
17 . Lights that indicate that anti-lock brakes are not working are:
Vehicles equipped with Anti-Lock Braking Systems (ABS) have yellow malfunction lights to indicate issues in the braking system.
18 . If the low air pressure warning signal comes on in a vehicle with air brakes, the driver should:
If the low air pressure warning signal comes on while you are operating a vehicle with air brakes, you should stop and safely park the vehicle as soon as possible. It is essential that you are able to stop safely while you still have some braking power remaining.
2025 Iowa | Frequently Asked Questions
To secure a CDL Bus endorsement in Iowa, you must first hold a valid Commercial Driver's License (CDL). You then need to pass the Passenger Transport Test, undergo a physical examination, and complete a skills test in the type of vehicle you'll be driving. Finally, you must pass a background check as mandated by Federal Motor Carrier Safety Administration.
To obtain a CDL Bus license, you must first have a valid driver's license. Then, pass the CDL general knowledge test, and the passenger transport test. You must also pass a physical examination and a skills test in the type of bus you will be driving. Finally, submit to a background check as required by the Federal Motor Carrier Safety Administration.
Yes, specific training is necessary for a CDL Bus endorsement. You must complete a commercial driver's education course, pass the general knowledge and passenger transport written tests, and successfully complete a skills test in the type of bus you'll be driving. Some states also require applicants to have a certain amount of driving experience.
CDL Bus licenses are classified into three main categories: Class A, B, and C. Class A is for vehicles with a combined weight over 26,001 lbs where the vehicle being towed is over 10,000 lbs. Class B is for single vehicles over 26,001 lbs not towing a vehicle over 10,000 lbs. Class C is for vehicles carrying 16 or more passengers including the driver or hazardous materials.
No, you cannot use your personal vehicle for the CDL Bus driving test. The test must be taken in the same type of vehicle for which you are trying to get licensed. This means you will need to take the test in a commercial bus similar to the one you will be driving professionally.
During the CDL Bus driving test, you'll be evaluated on several skills. These include pre-trip vehicle inspection, basic vehicle control (backing, turning, stopping), and on-road driving (including highway, city, and residential driving). You'll also be tested on specific bus maneuvers such as loading and unloading passengers, bus stop procedures, and emergency exit procedures.
Yes, there are additional medical prerequisites for a CDL Bus endorsement. You must pass a Department of Transportation (DOT) physical exam every 24 months. The exam assesses hearing, vision, blood pressure, and checks for conditions like diabetes or epilepsy that could affect your ability to safely operate a bus.
No, it's not permissible to transport passengers without a valid CDL Bus endorsement in Iowa. It's a requirement by law for drivers who operate a vehicle designed to carry 16 or more passengers, including the driver. Driving such a vehicle without the proper endorsement could result in serious legal consequences, including fines and suspension of your driving privileges.
Yes, the CDL Bus endorsement can be added to your existing CDL in Iowa. You don't need to apply for a new license, but you must pass the Passenger Transport test. Once you pass, the endorsement will be added to your current CDL. However, you may need to renew your license if it's close to its expiration date.
Yes, drivers with a CDL Bus endorsement must comply with federal and state regulations. These include maintaining a logbook of hours driven, undergoing regular medical examinations, and adhering to restrictions on alcohol consumption. Also, some states may have additional restrictions such as age limits and mandatory rest periods between driving shifts.