As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AIRCRAFT CABIN PRESSURIZATION FAILED ON CLIMB. AUTO FAIL WARNING LIGHT ILLUMINATED. CREW TRANSFERED TO STANDBY MODE BUT AIRCRAFT WOULD NOT PRESSURE. AIRCRAFT RETURNED AND LANDED WITHOUT INCIDENT.MAINTENANCE CHANGED THE CABIN PRESSURE CONTROLLER IAW MM 21-31-21 AND THE SYSTEM FUNCTION CHECKED SERVICEABLE.AIRCRAFT RETURNED TO SERVICE WITH NO FURTHER INCIDENTS TO REPORT.