As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED, UNABLE TO PRESSURIZE AIRPLANE AFTER TAKEOFF. FLIGHT CREW RETURNED AIRCRAFT TO TJSJ AND LANDED WITHOUT FURTHER INCIDENT. A GROUND PRESSURIZATION CHECK WAS PERFORMED, NO DEFECTS NOTED. AIRCRAFT WAS RETURNED TO SERVICE. (M)