What steps are involved in testing the anti-skid control unit?

• A. Use manufacturer test procedures to verify wheel speed sensor readings
• B. Test pedal input against wheel speed and check for fault codes
• C. Convert anti-skid software version in the flight computer
• D. Use manufacturer test procedures, verify wheel speed sensors readings, test pedal input vs wheel speed, and check fault codes

Answer: (D)

Testing the anti-skid control unit requires a comprehensive verification of how the system reads wheel speed, interprets braking input, and logs faults. Start by following the manufacturer’s test procedures exactly as written, using the approved test gear and acceptance criteria. This ensures you’re evaluating the unit under the intended conditions and with the right references.

Then confirm wheel speed sensor readings are accurate and consistent. The ASCU relies on precise wheel speed data to determine when slip is occurring and to modulate brake pressure accordingly. If a sensor is faulty, misreads, or has wiring issues, the control logic can apply or withhold braking incorrectly, which undermines the whole system.

Next, test pedal input against wheel speed to verify the relationship between brake demand and actual wheel behavior. This step checks that the driver’s braking request is properly translated into the control actions the ASCU commands, ensuring there’s correct coordination between pedal position or hydraulic signal and wheel speed responses.

Finally, check fault codes to ensure the system properly detects, stores, and communicates faults. Fault codes provide the diagnostic path if anything in the ASCU, sensors, or wiring is not functioning as it should. Having this information helps pinpoint where a problem lies and confirms that the system will alert maintenance when it’s out of specification.

Taking all of these steps together gives a full, reliable assessment of the anti-skid control unit. Skipping any part could miss a fault or lead to incorrect operation under real-world braking.