As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB OUT, CREW WENT TO PRESSURIZE AIRCRAFT AND THE CABIN DOOR ANNUNCIATOR ILLUMINATED. CREW RETURNED TO FIELD WITH NO FURTHER INCIDENT. THE CORRECTIVE ACTION WAS THAT MAINTENANCE REPLACED THE RIGHT INSTRUMENT AIR SHUT OFF VALVE. MORE INFORMATION WILL BE AVAILABLE AT LATER DATE.