District of columbia Driver’s Examination
Knowledge Test Class A
This license is required for driving any legal combination of vehicles, with a gross combination weight rating of 26,001 pounds or more, provided the GVWR of a trailer exceeds 10,000 pounds To receive this license, applicants must pass a 50-question test. To pass, applicants must answer 40 questions correctly. Each question has four possible answer choices. Test questions come from the Washington D.C. Commercial Driver License Manual. Questions come from chapters covering: Introduction, Driving Safely, Transporting Cargo Safely, Air Brakes (if applicable), Combination, Doubles and Hazardous Materials. Endorsements that may be used with a Class A CDL are: Hazardous materials, Tank, Passenger, HazMat and Tank, Air Brakes and School bus.
Number of Question
Passing Score
When driving, keeping space between your vehicle and other vehicles is:
Explanation
For the safety of everyone on the road, it is essential that you maintain adequate cushions of space between your vehicle and other vehicles. This will help ensure that if you need to stop your vehicle, you will be able to do so without hitting someone else.
To confirm that a trailer has ABS, you can:
Explanation
If you are unsure if a trailer is equipped with an Anti-Lock Braking System (ABS), look under the vehicle for the electronic control unit and wheel speed sensor wires coming from the back of the brakes.
What is a tire load?
Explanation
Tire load is the maximum weight that a tire can safely carry at a specified pressure. This will be stated on the side of a tire.
When checking the air and electrical lines during a vehicle inspection, all of the following should be true, except:
Explanation
When examining the air and electrical lines as part of your vehicle inspection test, you must listen for leaks. Ensure that the air hoses and electrical lines are not cut, chafed, spliced, or worn. Make sure air and electrical lines are not tangled, pinched, or dragging against tractor parts.
What are placards?
Explanation
Placards are diamond-shaped warning signs that are placed on the outside of vehicles carrying hazardous materials. Placards are used to identify the specific hazard classes of the cargo being carried.
When conducting a vehicle inspection, you will need to identify all of the following, except:
Explanation
During the vehicle inspection test, you must check the power steering belt, water pump belt, alternator belt, and air compressor belt for snugness, cracks, or frays. If any of these components are not belt-driven, you must tell the examiner which one(s), and verify that they are operating properly, mounted securely, and not damaged or leaking.
After a vehicle is started, warning lights and buzzers:
Explanation
