As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LCQ - EMERGENCY EQUIPMENT - DURING C-17 CHECK THE O2 DOOR LOCATED AT PASSENGER SERVICE UNIT (PSU) 23 RT FAILED TO OPEN DURING PASSENGER OXYGEN SYSTEM CHECK. MAINTENANCE REMOVED AND REPLACED THE ACTUATOR SOLENOID AT PSU 23 RT IAW BMM 35-22-21, OPERATIONAL CHECK WAS GOOD.