Which control activates the emergency signaling system when the FAP LED screen is not functioning?

• A. EVAC CMD
• B. FAP
• C. CMD
• D. EMERGENCY

Answer: (C)

The key idea is how the aircraft triggers emergency signaling when the primary indicator path (the FAP LED screen) is unavailable. There’s a dedicated manual control that bypasses the failed display and directly activates the emergency signaling circuits. That control is the CMD switch. Pressing CMD engages the emergency signaling system so cabin and cockpit crew are alerted despite the FAP not functioning.

The other options don’t fit the scenario: EVAC CMD is specific to initiating an evacuation sequence, not the general emergency signaling itself; the FAP is the display panel, not a control to activate signaling; and EMERGENCY is a generic label that isn’t the direct manual control needed when the FAP screen is down.