As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RECEIVED CABIN ALTITUDE MASTER WARNING MESSAGE IN FLIGHT AIRCRAFT ALTITUDE 12,000FT CABIN ALTITUDE 10,200FT, PRESSURIZATION WORKED IN NORMAL MODE. REF LOG 186158/1-COMPLIED WITH OPS CHECK OF CABIN PRESSURIZATION IN MANUAL MODE IAW AMM 21-31-00, OPS CHECK AND LEAK CHECK GOOD ON THE GROUND. (A)