As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON CLIMB OUT WITH CABIN PRESSURIZATION SET TO AUTO IN BOTH NORMAL AND CAB SET MODE THE RATE OF PRESSURIZATION WAS UNCONTROLLABLE UP TO MAX DIFF.A/C RETURNED TO DEPT AIRPORT. SYSTEM OPERATED SERV IN MANUAL MODE. COMPUTER REPLACED AND FUNCTION CHECKS CARRIED OUT SERV.NO STRIP REPORT FROM REPAIR FACILITY AS OF YET.