As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WILL NOT PRESSURIZE IN MANUAL. RETURNED TO PDX. REMOVED AND CLEANED CONNECTIONS AND TUBES ON PNEUMATIC VALVE AND REFERENCE FITTING MANUAL SYSTEM, OPS CHECKS GOOD. VERIFIED AUTO PRESSURIZATION SYSTEM DEFERRED AND MAINTENANCE ACTIONS COMPLIED WITH IAW MEL 21311A.