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To obtain a Iowa Commercial Learner’s Permit (CLP), you must pass the state CDL General Knowledge Exam. The CLP will allow you to practice driving under supervision for 180 days. Then, to obtain a Iowa CDL, you must pass the Pre-Trip Inspection Test, which is a federal requirement (49 CFR § 392.7 and 49 CFR § 396.13). This portion is one of three parts that must be passed in Iowa’s CDL skills exam (the other two are the basic control skills test and the road test). Designed to ensure that drivers can recognize and evaluate the condition of their vehicle’s components, failing even one part of the skills test results in a total test failure. Failing the Knowledge Exam means delaying your CLP by at least one day, as you’ll have to reschedule and likely pay a retest fee. Our Iowa Pre-Trip Inspection Practice Tests are your key to passing the General Knowledge Test on your first attempt.
The Iowa General Knowledge Exam and Pre-Trip Inspection Test evaluate your ability to inspect engine components, brakes, suspension, and lights, among other items. During the pre-trip inspection test, you will be required to point to and explain each part’s function and why it must be checked. Examiners must determine that you can properly ensure your vehicle is in safe operating condition. Without passing, you will not be granted a CDL, and you cannot drive commercially. While a CLP allows you to drive with supervision, obtaining a full CDL is necessary for independent commercial driving.
For both the Iowa CDL General Knowledge Exam and the CDL Pre-Trip Inspection Test, you’ll need to familiarize yourself with Iowa’s inspection procedure, which is a systematic pre-trip vehicle check. To ensure road safety and compliance, the inspection includes reviewing past inspections, inspecting the engine compartment, checking in-cab controls and gauges, verifying lights, conducting a full walk-around inspection, testing signal lights, and assessing the brake system.
The 20 multiple-choice-question practice test is based on the most recent Iowa CDL manual (Iowa CDL Handbook 2025) and assesses your knowledge of pre-trip inspections. A detailed explanation is provided after each response to speed learning and help you pass the official knowledge test on your first attempt.
We have additional practice tests to prepare you for other parts of the General Knowledge Test. Check them out!
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