As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LOST CABIN PRESSURIZATION ON DESCENT. CABIN ALT @10200 DURING DESCENT FL23000. NO EICAS MESS. RAN QRH WENT TO MANUAL TO DECREASE CABIN ALT---- PERFORMED OPERATIONAL CHECK OF PRESSURE CONTROL SYS IN MANUAL MODE OPS CHECK GOOD. PERFORMED OPERATIONAL TEST IN AUTO MODE OPS CKECK GOOD. CLEANED OUTFLOW VALVES, GVI OF OUTFLOW VALVES NO FAULTS. CHECKED FOR PRESS LEAKS, NONE FOUND. ACFT OK FOR SERVICE.