Free District of Columbia CDL Air Brakes Practice Test 2022

Do you need an Air Brakes endorsement or an L endorsement for your commercial driving license? The District of Columbia CDL Air Brake 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 DC CDL practice test questions are relevant, all of them are based on the DC CDL 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 CDL practice test to get ready to pass the District of Columbia CDL Air Brake Test now. 

Our CDL practice tests:
Based on 2022 DC commercial driver's license manual
Full answers + detailed explanations
Perfect for first-time, renewal applicants
DC CDL Air Brakes Test format:
25 questions
20 correct answers to pass
80% passing score
List of questions
1.
An application pressure gauge shows how much air you are applying to the brakes. Increased application pressure to maintain the same speed indicates that __________.
2.
Air tanks need to be drained ______.
3.
The low air pressure warning signal indicates:
4.
Where is the modulating control valve located on some vehicles?
5.
When the air system is low ________.
6.
The type of brakes that clamp the rotor between the brake shoes is:
7.
Air governor cut-out should be at around:
8.
When you need to depress the brakes harder and harder just to maintain the same speed this means ______.
9.
What type of brakes pushes a wedge between the ends of two brake shoes to stop the vehicle?
10.
When your brake's main air pressure is lost ________.
11.
When does the air compressor governor allow air to start pumping?
12.
When checking the air pressure buildup, pressure should build:
13.
The manual adjustment of automatic slack adjusters is:
14.
The emergency spring brake release knob is:
15.
A device that limits the amount of air provided to the front brakes is a:
16.
You should avoid using the parking brake when _______.
17.
Pushing the brake pedal down harder __________.
18.
The most common type of foundation brake is?
19.
Brake linings should not be _______.
20.
If air supply drops when driving, the tractor protection valve ________.
21.
Spring brakes are applied:
22.
The parking brake should be used:
23.
What does ABS stand for?
24.
The warning light and buzzer will come on when the air pressure in either system drops below what psi?
25.
What happens when pressure is put on the air brakes?