District Of Columbia cdl Air Brakes - Test 1
Number of questions: 25
Passing score: 80%
Acceptable number of errors: 5
This endorsement is required for driving a vehicle with air brakes. To receive this endorsement, applicants must pass a written test. The test consists of 25 multiple choice questions. Each question has four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the Washington D.C. Commercial Driver License Manual. Questions come from the chapter covering: Air Brakes. The Air Brakes endorsement may be used with the Class A, B or C CDL.
To DMV Handbooks3. What is brake lag?
The time required for the brakes to work after the brake pedal is pushed
The distance between the brake pedal’s resting position and the floor
The amount of air pressure used to stop a vehicle
How faded the brakes are