As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB OUT CABIN PRESSURIZATION WOULD NOT STABILIZE IN AUTO MODE. DEFERRED PRESSURIZATION CONTROL AUTO MODE SYS IAW MEL 21-16. AFTER PUSHBACK ACFT UNCONTROLLABLE CABIN ALT READ OUT WENT TO DASHES, DIFFICULTY IN MANUAL MODE. REPLACED DIGITAL CONTROLLER IAW AMM 21-31-01. OPERATIONS CHECKED GOOD, MANUAL PRESS OPERATIONS CHECKED GOOD IAW AMM 21-31-00.