200+ Free California CDL Air Brakes Test Practice Questions
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In which scenario should you NOT use the parking brake?
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Key Facts: California CDL Air Brakes Test Exam
80%
Federal CDL Knowledge-Test Minimum
49 CFR 383.135
55-75 psi
California Low-Air Warning Range
California Commercial Driver Handbook Section 5
20-45 psi
Spring Brake Application Range
California Commercial Driver Handbook Section 5
85-100 psi / 45 sec
Dual-System Buildup Check
California Commercial Driver Handbook Section 5
$100
CA Restriction Removal Fee When Driving Test Required
California DMV Licensing Fees
California air-brake preparation should use California Commercial Driver Handbook Section 5. Key California values include governor cut-out around 125 psi, cut-in around 100 psi, low-air warning between 55 and 75 psi and before 55 psi on the skills-test check, spring brake application around 20-45 psi, dual-system buildup from 85 to 100 psi within 45 seconds, applied leakage limits of 3/4/6 psi, and static leakage limits of 2/3/5 psi. FMCSA and 49 CFR 383.95 require air-brake restrictions when the knowledge, component, air-check, or representative-vehicle requirements are not met.
Sample California CDL Air Brakes Test Practice Questions
Try these sample questions to test your California CDL Air Brakes Test exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 200+ question experience with AI tutoring.
1In the California CDL Air Brakes test, what component compresses air for the air brake system?
2What is the typical air compressor governor cut-out pressure range?
3At what pressure does the air compressor governor typically cut IN to resume pumping?
4What is the purpose of the air dryer in the brake system?
5What is the function of the wet tank (supply or service reservoir)?
6At what pressure does the safety valve in the supply tank typically open to release excess air?
7What is the role of the foot valve (also called the treadle or service brake valve)?
8What does the brake chamber do?
9What is the role of the slack adjuster on an S-cam brake?
10What does the S-cam do in an S-cam drum brake?
About the California CDL Air Brakes Test Exam
The California CDL Air Brakes Knowledge Test covers the air-brake material in California Commercial Driver Handbook Section 5. Drivers must understand compressed-air components, tank drainage, low-air warning devices, leakage and buildup tests, spring and parking brakes, dual air systems, ABS, brake lag, downgrade braking, foundation brakes, and the air-brake restriction rules that affect CLP/CDL issuance and restriction removal.
Assessment
California DMV knowledge testing based on the California Commercial Driver Handbook, plus air-brake component identification and in-cab air-brake systems checks during skills testing when applicable
Time Limit
No separate official Air Brakes-only time limit published; California DMV does not administer knowledge tests within 30 minutes of closing
Passing Score
80% federal CDL knowledge-test minimum
Exam Fee
$100 to remove an air brake or automatic transmission restriction when a driving test is required; standard commercial application fees may apply (California Department of Motor Vehicles under FMCSA CDL standards)
California CDL Air Brakes Test Exam Content Outline
Air Brake Components and Air Supply
Compressor, governor, air tanks, drains, alcohol evaporator, safety valve, foot valve, gauges, low-air warnings, and legacy limiting valves.
California Air Brake Inspection Tests
Applied leakage, static leakage, low-air warning, spring brake, pressure buildup, parking brake, service brake, and skills-test verbalization requirements.
Spring, Parking, Dual, and Emergency Systems
Spring brakes, parking controls, modulating and dual parking valves, primary/secondary systems, check valves, and low-air emergency response.
ABS, Brake Lag, and Driving Technique
ABS requirements and lamps, braking with ABS, controlled braking, stab braking, brake lag distance, brake fade, and downgrade braking.
Foundation Brakes and Adjustment
S-cam, wedge, and disc brakes; slack adjusters; automatic adjuster cautions; drums, linings, hoses, and inspection defects.
How to Pass the California CDL Air Brakes Test Exam
What You Need to Know
- Passing score: 80% federal CDL knowledge-test minimum
- Assessment: California DMV knowledge testing based on the California Commercial Driver Handbook, plus air-brake component identification and in-cab air-brake systems checks during skills testing when applicable
- Time limit: No separate official Air Brakes-only time limit published; California DMV does not administer knowledge tests within 30 minutes of closing
- Exam fee: $100 to remove an air brake or automatic transmission restriction when a driving test is required; standard commercial application fees may apply
Keys to Passing
- Complete 500+ practice questions
- Score 80%+ consistently before scheduling
- Focus on highest-weighted sections
- Use our AI tutor for tough concepts
California CDL Air Brakes Test Study Tips from Top Performers
Frequently Asked Questions
What should I study for the California CDL Air Brakes test?
Study California Commercial Driver Handbook Section 5: Air Brakes. It covers system parts, tank drainage, low-air warning devices, spring brakes, ABS, dual air systems, air leakage and buildup tests, foundation brakes, and correct air-brake driving technique.
What score do I need to pass the air-brake knowledge test?
Federal CDL rules require at least 80% on CDL knowledge tests. California DMV also says applicants get three attempts to pass each required knowledge test on the application.
What is the California low-air warning threshold?
California’s handbook says a visible warning must come on between 55 and 75 psi, or one-half governor cut-out on older vehicles. For the skills-test low-air warning check, the warning devices must activate before pressure drops below 55 psi or the manufacturer-specified level.
What are the California air leakage limits?
For the applied leakage test, California lists 3 psi in one minute for a single vehicle, 4 psi for a two-vehicle combination, and 6 psi for a combination of three or more vehicles. For the static leakage test, the limits are 2, 3, and 5 psi respectively.
How do I avoid an L air-brake restriction?
You must pass the air-brake knowledge component and, when skills testing applies, correctly identify air-brake components, properly conduct the air-brake systems check, and test in a vehicle with the required air-brake equipment. FMCSA and 49 CFR 383.95 require restrictions when those requirements are not met.
How much does California charge to remove an air brake restriction?
California DMV’s licensing-fees page lists $100 for removing an air brake or automatic transmission restriction when a driving test is required. Other commercial application, medical, training, and retest costs may also apply.