As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ACFT WILL NOT DEPRESSURIZE UNTIL ACFT HAS LANDED. FOUND TEE FITTING FOR AUX VOLUME TANK CRACKED. REMOVED AND INSTALLED NEW TEE FITTING, FOUND VACUUM SHUTOFF VALVE CRACKED. REMOVED SHUTOFF VALVE, AND INSTALLED NEW VALVE, IAW MM 21-31-02. PERFORMED ENGINE RUNS AND TESTED PRESSURIZATION SYS OPS CHECK IAW MM 21-31-00. SYS OPS CHECK OK. REINSTALLED CABIN INTERIOR REMOVED TO GAIN ACCESS TO SYS.