# Free California CDL Air Brakes Practice Test 2023

Do you need an Air Brakes endorsement or an L endorsement for your commercial driving license? The California CDL Air Brake test has some differences from other endorsements because your license will receive a mark of restriction if you fail the test. So having good preparation before exam day is very necessary. To ensure that our questions are relevant, all of our California CDL practice test questions are based on the California Commercial Driver's Manual. Each question has a detailed explanation for you to thoroughly learn the format and the topic. Don't be afraid of having a restriction on your license. Let’s try with our free CDL Practice Test pack to get ready to pass the California CDL Air Brake Test now.

Our CDL practice tests:
Based on 2021 CA commercial driver's license manual
Perfect for first-time, renewal applicants
CA CDL Air Brakes Test format:
25 questions
80% passing score
List of questions
1.
A low air pressure warning signal is ________.
2.
All air brake equipped vehicles have:
3.
Your truck or bus has a dual air brake system. If a low air pressure warning comes on for only one system, what should you do?
4.
If your truck has a properly functioning dual air brake system and minimum size air tanks, the air pressure should build up from 85 to 100 psi within how many seconds?
5.
The 3 individual systems of the air brakes are the service brakes, emergency brake, and:
6.
The spring brakes used on the chambers in a straight truck will bring you to a stop when air pressure drops below ___ psi.
7.
When the air system is low ________.
8.
What negatively affects the braking power of a spring brake?
9.
10.
When your brake's main air pressure is lost ________.
11.
If your truck has a dual air brake system, and one of the systems is low on pressure:
12.
All of the following are factors in total stopping distance, EXCEPT:
13.
After the initial pressure drop, air leakage for combination vehicles should be less than:
14.
Under normal braking conditions, the vehicle ______.
15.
The brake pedal in an air brake system _______.
16.
When inspecting the air brake system, what particular item in the engine compartment should the driver pay specific attention to?
17.
Why should you check the brake adjustment often?
18.
In tractors and straight trucks spring brakes will come on fully when the air pressure drops to what range?
19.
How are brakes designed?
20.
Brake linings should not be _______.
21.
Why do air brakes take longer to stop than hydraulic brakes?
22.
The spring brakes of a tractor will come on when the air pressure falls within _______.
23.
The governor stops the compressor from pumping air at:
24.
In a dual air brake system, one system will typically control the rear brakes, and the other:
25.
What is the function of a safety valve?