When does the amber CABIN PRESSURE CAS message trigger?

• A. When the cabin differential exceeds 6.0 PSID
• B. When the cabin differential exceeds 6.35 PSID
• C. When the cabin altitude exceeds 10,500 feet
• D. When the cabin differential drops below -0.25 PSID

Answer: (A)

The instrument cluster is monitoring the difference between inside cabin pressure and outside ambient pressure, which is the cabin differential. The amber CABIN PRESSURE CAS warning is issued when that differential pushes beyond the caution limit, signaling you are approaching a potentially unsafe over-pressurization condition. In this airplane, that caution threshold is 6.0 PSID, so crossing that value triggers the amber warning to alert you to check and adjust the pressurization system or operating altitude. If the differential continues to rise toward the allowable maximum, you’d see further indications or actions, but the amber message specifically corresponds to exceeding the 6.0 PSID limit. The other scenarios—cabin altitude alone, or a negative differential, or a higher 6.35 PSID value—do not cause this amber warning in this context, as they correspond to different conditions or alerts.