Alabama CDL Air Brakes study guide
Alabama CDL Air Brakes · Work through your exam, one topic at a time.
The Alabama CDL Air Brakes knowledge test is the written exam a commercial driver must pass to have the air brake restriction removed from a Class A or Class B commercial learner permit or license. It is for drivers who will operate vehicles equipped with air-actuated brakes - tractors and trailers, dump trucks, buses, and similar heavy equipment - and who therefore need to show they understand how those systems work before they are allowed to drive them. The Alabama CDL Air Brakes study guide has 6 sections and about 1,678 words.
01Air Brake System Components and Functions
An air brake system is a network of parts that stores, moves, and applies compressed air to slow and stop the vehicle. The compressor , driven by the engine, builds pressure and sends air through the system.
277 words, about 1 min02Dual Air Brake System Operation
Most modern air brake vehicles use a dual air brake system : two separate circuits, typically a primary and a secondary system, each with its own reservoir. The circuits are isolated so that a failure in one does not automatically drain the other.
291 words, about 1 min03Inspecting Air Brake Systems
A proper inspection catches problems before they become emergencies. Begin with a walk-around : check for leaks, damaged hoses, cracked lines, and loose fittings.
259 words, about 1 min04Air Brake Tests and Checks
Air brake tests verify that the system builds, holds, and releases pressure correctly. A standard sequence includes the compressor build-up test , the leak test , and the low pressure warning and spring brake test .
304 words, about 2 min05Using Air Brakes Safely
Safe use of air brakes starts with understanding that air brakes are not instantaneous. There is a slight lag between pressing the pedal and the brakes applying, so you must plan ahead and increase following distance.
259 words, about 1 min06Air Brake System Malfunctions and Emergencies
Air brake emergencies usually involve loss of air pressure or a component failure . If pressure drops, the low pressure warning activates, and if pressure continues to fall, the spring brakes apply automatically.
288 words, about 1 min