As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DEPARTED LAX, PRESSURIZATION DID NOT WORK. FOLLOWED SOP. NO PRESSURIZATION IN ANY MODES OR CONTROLLERS. RETURNED TO LAX. INSTALLED SERVICEABLE SECONDARY OUTFLOW VALVE IAW 21-31-00. OPS CHECK FAILED. DEFERRED THE PRESSURIZATION SYSTEM. 1/9/02 UPDATE: FAT MAINTENANCE WAS UNABLE TO DUPLICATE THE SQUAWK. S/N ON 110-F0399, S/N OFF 81-F0526.