Combination #1
Combination Vehicles Practice Test | Iowa 2025 #1 Page 3 of 3
Train for FREE online with our Iowa CDL combination vehicle 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 combination 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 DMV requirements for issuing a combination license may vary from state to state.
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15 . Having anti-lock brakes on only one axle:
If a vehicle has anti-lock brakes on just one axle, the driver will still have more control during braking than they would without any anti-lock brakes.
16 . A driver should test the tractor protection valve by:
You should test the tractor protection valve by allowing the air supply to properly charge, turning off the engine, then releasing air from the system by pressing the brake pedal several times. The tractor protection valve should move into its emergency position when psi drops to an unsafe level.
17 . A trailer that is too high:
Before coupling together a tractor and a trailer, you should make sure the trailer is at the proper height. If the trailer is too low, the trailer nose may be damaged. If the trailer is too high, it may not be able to couple correctly.
18 . The trailer hand valve should be used:
The trailer hand valve (also referred to as the "trolley valve" or "Johnson bar") works the trailer brakes and should be used only when testing them. Using the trailer hand valve while driving could result in a skid.
19 . Older trailers are not equipped with spring brakes. This means that if the air supply for a vehicle's air braking system leaks away:
Older trailers do not have spring brakes. This means that if the air supply in an older trailer's air tank has leaked away, there will be no working brakes connected to the trailer and its wheels will turn freely.
20 . If the emergency air line loses pressure:
The emergency air line controls the emergency brakes on a combination vehicle. A loss of air pressure in the emergency line will cause the emergency trailer brakes to activate.
See the exact questions that will be on the 2025 Iowa DMV exam.
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2025 Iowa | Frequently Asked Questions
To acquire a CDL Hazmat endorsement in Iowa, you need to pass the Hazardous Materials Endorsement Knowledge Test. Additionally, you must undergo a federal background check and fingerprinting. The TSA will assess your application and once approved, the Iowa Department of Transportation will add the endorsement to your CDL.
To obtain a CDL Hazmat license, you must first possess a valid Commercial Driver's License (CDL). You also need to be at least 21 years old, a U.S. citizen or have legal status, and be able to read and speak English. Additionally, you must pass the Hazardous Materials Endorsement Knowledge Test and undergo a federal background check and fingerprinting.
When applying for a CDL Hazmat endorsement in Iowa, you'll need to provide proof of U.S. citizenship or permanent residency, proof of identity, and proof of Iowa residency. Additionally, you'll need to bring your current CDL. A TSA background check and fingerprinting are also required, for which separate documentation may be needed.
Yes, there is a dedicated written test for the CDL Hazmat endorsement. This test is called the Hazardous Materials Endorsement Knowledge Test. It covers topics such as loading and unloading hazardous materials, bulk packaging marking, driving and parking rules, and emergency response procedures.
The written test for the CDL Hazmat endorsement in Iowa covers a wide range of subjects. These include understanding hazardous materials regulations, safety procedures, proper use of shipping papers, placarding, loading/unloading, bulk packaging marking, compatibility and segregation of cargo, and emergency response procedures.
Yes, there are additional fees associated with obtaining a CDL Hazmat endorsement in Iowa. These include a fee for the knowledge test, a fee for fingerprinting, and a fee for the TSA background check. The specific amounts can vary, so it's best to check with the Iowa Department of Transportation for the most current costs.
Yes, obtaining a CDL Hazmat endorsement in Iowa requires a background check. The Transportation Security Administration (TSA) conducts this check, which includes a review of your criminal, immigration, and FBI records. This ensures that you do not pose a security threat while transporting hazardous materials.
Yes, specialized training is required for the CDL Hazmat endorsement in Iowa. This involves understanding hazardous materials regulations, emergency response procedures, and safety protocols. After training, you must pass a written test to get certified. This ensures that drivers are equipped with necessary knowledge to handle hazardous materials safely.
No, you cannot legally transport hazardous materials in Iowa without a valid CDL Hazmat endorsement. This endorsement is required by federal law and ensures that drivers have the necessary knowledge and skills to safely transport hazardous materials. Violating this requirement can result in severe penalties, including fines and suspension of your CDL.
You can add a Hazmat endorsement to your current CDL in Iowa. You don't need to apply for a new CDL. However, you must pass a written test on hazardous materials and complete a TSA security threat assessment, which includes fingerprinting and a background check, to obtain the endorsement.
