As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 1228 EWR FLIGHT CREW REPORTED ACFT NO PRESSURIZING IN CLIMBING. AIR CREW PERFORMED AIR RETURN AND LANDED UNEVENTFULLY. EWR MX R&R DIGITAL PRESSURIZATION CONTROLLER AND PERFORMED OPS CHECK SUCCESSFULLY. ACFT WAS APPROVED TO RETURN TO SERVICE.