Free Practice Questions for Hawaii CDL Air Brakes
Exam-style questions and explanations by OpenExamPrep.
Loading practice questions...
Explore More CDL Air Brakes Knowledge Test
Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.
7 Job WikiKey Facts: Hawaii CDL Air Brakes Exam
80%
Minimum passing score on the air brake knowledge test
49 CFR 383.135
55 psi
Level the low air pressure warning must come on before
Hawaii CDL Manual Section 5.1.11
20 to 45 psi
Air pressure range where spring brakes come fully on
Hawaii CDL Manual Section 5.1.14
About 125 psi
Typical governor cut-out pressure
Hawaii CDL Manual Section 5.1.2
150 psi
Usual safety valve opening pressure
Hawaii CDL Manual Section 5.1.6
Code L
Restriction for not passing the air brake test or testing without air brakes
Hawaii CDL Manual Section 1
Hawaii drivers of air-braked commercial vehicles must pass the Air Brakes knowledge test (80% to pass) or carry restriction L. The test covers Section 5 of the Hawaii CDL Manual: compressor and governor, tank drains, spring brakes, dual systems, the air brake check, brake lag, fade, and downgrade braking.
Sample Hawaii CDL Air Brakes Practice Questions
Try these sample questions to review concepts for the Hawaii CDL Air Brakes exam. Each question includes a detailed explanation. Start the interactive quiz above for the full 189+ question experience with AI tutoring.
1In Hawaii, what happens to your CDL if you do not pass the air brakes knowledge test?
2Leilani passes the air brakes knowledge test but takes her skills test in a straight truck with hydraulic brakes. Which restriction does the Hawaii manual say she receives?
3A bus with air-over-hydraulic brakes is used for a Hawaii CDL skills test. Which restriction will the license carry?
4A Hawaii CDL holder with an air brake restriction now wants it removed. What does 49 CFR 383.135 require?
5During a Hawaii CDL skills test, the applicant fails the air brake check. What happens, according to the Hawaii manual?
6According to Section 1.1.1 of the Hawaii CDL manual, who must take the air brakes knowledge test?
7What score must you reach on the air brake portion of the knowledge test to avoid the air brake restriction under 49 CFR 383.135?
8Section 5 says air brakes are really three different braking systems. Which three?
9How is the emergency brake system described in Section 5?
10Your bus's air compressor has its own oil supply. What does Section 5.1.1 say to do?
About the Hawaii CDL Air Brakes Exam
The Hawaii CDL Air Brakes knowledge test is required to drive a commercial vehicle with air brakes, including air-over-hydraulic brakes. Without it, or if you take the skills test in a vehicle without air brakes, your license carries Code L; testing in an air-over-hydraulic vehicle brings Code Z. This independent English-language multiple-choice practice bank helps you study Section 5 of the Hawaii CDL Manual; it is a study aid, not a copy of the official test, and it does not replace a hands-on air brake inspection.
Exam sponsor: Hawaii Department of Transportation & County Licensing Divisions. The requirements and fees below concern the certification or admission exam, separate from our free practice resources.
Assessment
The Air Brakes knowledge test covers Section 5 of the Hawaii CDL Manual and is required if your vehicle has air brakes, including air-over-hydraulic brakes. During the skills test, the air brake check is part of the pre-trip inspection; in Hawaii, failing it is an automatic pre-trip failure and ends the test. Air brakes are a restriction (Code L or Z), not an endorsement.
Time Limit
No published time limit for the Air Brakes knowledge test; the Hawaii skills test allows up to 1.5 hours in a Class B or smaller vehicle (2 hours in Class A)
Passing Score
At least 80% correct on each CDL knowledge test; scoring below 80% on the air brake portion brings an air brake restriction (49 CFR 383.135)
Exam / Certification Fees
$5 Air Brakes knowledge test; $15 general knowledge test; $30 permit application; $50 prepaid skills-test appointment; $40 license fee after passing (Hawaii CDL Manual, June 2025)
Exam sponsor websiteFees, eligibility, and exam policies can change. Confirm them with the exam sponsor before applying or paying.
Official sources
- HDOT Motor Vehicle Safety Office - Commercial Drivers · Source checked 2026-10-02
- Hawaii Commercial Driver License Manual (June 2025) · Source checked 2026-10-02
- City and County of Honolulu - Commercial Driver Licensing (CDL) Office · Source checked 2026-10-02
- HRS § 286-236 - Commercial driver's license qualification standards · Source checked 2026-10-02
- 49 CFR 383.135 - Passing knowledge and skills tests · Source checked 2026-10-02
Our practice resources: topics covered
We aim to reflect publicly available exam outlines and topic information in our study resources. Coverage, format, and difficulty may differ from the actual exam, and we cannot guarantee that every detail is accurate or current. Confirm exam requirements, fees, and policies with the official exam sponsor.
Hawaii Air Brake Rules
Who must take the test, restriction codes L and Z, the 80% passing standard, removing a restriction, and Hawaii's automatic pre-trip failure for a failed air brake check.
Air Brake System Parts
Compressor and governor (cut-out about 125 psi, cut-in about 100 psi), tank drains, alcohol evaporator, safety valve (usually 150 psi), foundation brakes, gauges, low-air warnings (before 55 psi; 80 to 85 psi on many large buses), spring brakes (20 to 45 psi), parking controls, and ABS.
Dual Air Brake Systems
Primary and secondary systems, the axles each typically serves, building at least 100 psi in both before driving, and what happens when one system loses pressure.
Inspecting Air Brakes
Compressor belt, slack adjusters (more than about one inch of movement), automatic adjusters, drums and linings, governor test, static and applied leakage limits, low-air warning test, spring brake test, buildup rate, and parking and service brake tests.
Using Air Brakes
Normal stops, ABS braking, controlled and stab braking, brake lag (about 32 feet at 55 mph), brake fade, the downgrade braking technique, low air pressure, and parking-brake use.
Preparing for the Hawaii CDL Air Brakes Exam
What You Need to Know
- Passing score: At least 80% correct on each CDL knowledge test; scoring below 80% on the air brake portion brings an air brake restriction (49 CFR 383.135)
- Assessment: The Air Brakes knowledge test covers Section 5 of the Hawaii CDL Manual and is required if your vehicle has air brakes, including air-over-hydraulic brakes. During the skills test, the air brake check is part of the pre-trip inspection; in Hawaii, failing it is an automatic pre-trip failure and ends the test. Air brakes are a restriction (Code L or Z), not an endorsement.
- Time limit: No published time limit for the Air Brakes knowledge test; the Hawaii skills test allows up to 1.5 hours in a Class B or smaller vehicle (2 hours in Class A)
- Exam / certification fees: $5 Air Brakes knowledge test; $15 general knowledge test; $30 permit application; $50 prepaid skills-test appointment; $40 license fee after passing (Hawaii CDL Manual, June 2025) Official sources
Using Our Practice Resources
- Work through all 189 available questions
- Review every answer and explanation
- Track weak areas and revisit them
- Use our AI tutor for tough concepts
Hawaii CDL Air Brakes: Suggested Study Strategy
Frequently Asked Questions
Is Air Brakes an endorsement in Hawaii?
No. Air brakes are handled as a restriction. If you don't pass the air brake knowledge test, or your skills-test vehicle has no air brakes, Hawaii adds Code L (no air brake equipped CDL vehicle); testing in an air-over-hydraulic vehicle adds Code Z.
What is the passing score for the Hawaii CDL Air Brakes test?
Federal rule 49 CFR 383.135 requires at least 80% correct. An applicant who scores below 80% on the air brake portion and is issued a CLP or CDL gets an air brake restriction.
At what pressure must the low air pressure warning come on?
The Hawaii manual says a visible warning must come on before tank pressure falls below 55 psi (or one-half the governor cut-out pressure on older vehicles). On large buses, warnings commonly signal at 80 to 85 psi.
What are the maximum air leakage rates?
With the engine off and brakes released, the loss should be less than 2 psi in one minute for a single vehicle and less than 3 psi for a combination. With the brake pedal held down, more than 3 psi (single) or 4 psi (combination) in one minute is too much.
What happens if I fail the air brake check during the Hawaii skills test?
The Hawaii manual says failing the air brake test is an automatic failure of the pre-trip inspection, and the test is discontinued. All three parts of the skills test must be passed at the same appointment, so the test must be rescheduled.
How do I brake on a long, steep downgrade?
Get into the proper low gear before starting down. When you reach your safe speed, brake hard enough to feel a definite slowdown until you are about 5 mph below it (about three seconds), release, and repeat when you are back at the safe speed. Engine braking does most of the work.