Air Brakes
This endorsement is required for driving a vehicle with air brakes. To receive this endorsement, applicants must pass a test. The test consists of 25 multiple choice questions. Each question has three answer choices. To pass, the applicant must answer at least 20 questions correctly. Test questions come from the California Commercial Driver Handbook. Questions come from chapters covering: Air Brakes. The Air Brakes endorsement may be used with the Class A, B or C CDL.
Number of Question
Passing Score
7. Once the air tanks are at an air pressure level of 125 psi, the air compressor governor will:
Explanation
An air compressor governor will stop the compressor from pumping air once the air tanks are at an air pressure level around 125 psi. This air pressure level is referred to as the "cut-out" level.
8. When parking, you should not use the parking brake if:
Explanation
If your brakes are hot after coming down a steep grade, you should not use your parking brake when parking. Let your brakes cool before applying the parking brake or risk damaging the brakes.
9. Vehicles equipped with Anti-Lock Braking Systems (ABS) have ____ malfunction lamps to indicate when the ABS is not working.
Explanation
Vehicles with ABS have yellow malfunction lamps to alert drivers when the braking systems are not working. Be sure you know where the malfunction lamp on your vehicle is before beginning a trip.
10. Brake linings should be:
Explanation
Brake linings should not be loose or soaked with oil or grease. They shouldn't be dangerously thin.
11. Both systems in a dual air brake systems share:
Explanation
Both systems in a dual air brake system share a single air compressor. If the air compressor is damaged, neither system will be able to operate properly.
12. You should ____ if the low pressure warning signal activates while you are driving.
Explanation
