As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
OUTFLOW VALVE POSITION INDICATOR ERRATIC. CYCLING BETWEEN OPEN AND CLOSED. PRESSURIZATION NORMAL. GROUNDED - YES. SPOKE WITH FLIGHT CREW UPON ARRIVAL. ACCOMPLISHED FIM TASK 21-31 TASK 801. NO FAULTS ON BOTH CONTROLLERS AND NO FAULT HISTORY. REPLACED CABIN PRESSURE CONTROL MODULE IAW AMM 21-31-02/401. ACCOMPLISHED GROUND VERIFICATION TEST PER AMM TASK 21-31-00-700-802 AND TASK 21-31-00-710-801. NO FAULTS NOTED.