As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW 02 SYSTEM FAILS PREFLIGHT TEST. DISPLAYS REG LO PRESSURE W / CREW SUPPLY ON. ALL 02 MASKS. C/A: DEFER PER MEL 35-13-01B, M PROC C/W PER A320 AMM 35-10. MC NOTIFIED, PLACARD INSTALLED. PER MC, PRESS GUAGE WILL REMAIN IN FLT DECK. GUAGE BELONGS TO AUSTIN (AUS 250). R/R CREW OXYGEN LP SOLENOID VALVE PER A320 AMM 35-13. OPS TESTS AND LEAKS CHECK GOOD. NO DEFECTS NOTED. AIRCRAFT WAS GROUNDED