As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PASSENGER DOOR LATCH CAUTION MESSAGE AFTER TAKEOFF. FOLLOWED QRH NO PRESSURIZATION PROBLEMS. CONTINUED TO GSO. CLIMBING THROUGH 20,000 PASSENGER DOOR WARNING. STILL NO PRESSURE PROBLEMS. RETURNED TO DFW. AFTER LEVELING AT 11,000 COMING BACK TO DFW, DOOR WARNING BECAME PAX DOOR LATCH WITH DIFFERENTIAL 4.6. CAUTION MESSAGE CLEARED AFTER LANDING. FOUND MDC FLAGGED PSEU. REMOVED AND REPLACED PSEU IAW CL600 MM 32-61-01. PRESSURIZED AIRCRAFT ON GROUND WITH NO DOOR INDICATION. NO FURTHER FAULTS IN MDC. SYSTEM OPS CHECK GOOD AT THIS TIME.