Air Brakes
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 three or four answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the State of Delaware 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.
Number of Question
Passing Score
13. The ____ are activated by an electric switch that is triggered by the brake pedal.
Explanation
In a vehicle with air brakes, the brake lights are activated when the brake pedal is pushed and air pressure moves an electric switch. With the application of air pressure, the switch will then turn on the brake lights.
14. What kind of force do emergency brakes use?
Explanation
Air brakes are really three different braking systems: the service brake, the parking brake, and the emergency brake. Emergency and parking brakes are applied with mechanical force.
15. An air compressor governor will stop the compressor from pumping air once the air tanks have an air pressure level of:
Explanation
An air compressor governor will stop the compressor from pumping air once the air tanks are at an air pressure level of 125 psi. This air pressure level is referred to as the "cut-out" level.
16. What color are ABS malfunction lamps?
Explanation
Vehicles with Anti-Lock Braking Systems (ABS) have yellow malfunction lamps.
17. Service brakes should:
Explanation
Before driving, you should always verify that your service brakes are in good working order. Testing the brakes before a trip allows you to locate any problems before you need to brake while on the road.
18. How should you test the low pressure warning signal?
Explanation
