What was found
WHILE ENROUTE, DURING CLIMB AT 15000, SYS PRESS LIGHT AS WELL AS FAULT LIGHT ON PRESSURIZATION CONTROL PANEL MANUAL & AUTO BUTTON IN AUTO MODE. REGAINED CONTROL IN MANUAL MODE AFTER TURNING BLEED AIR OFF THEN BACK ON, CREW DECIDED TO DIVERT BACK FOR MX. FOUND CABIN PRESSURE CONTROLLER FAULT, RESEATED CONNECTOR PLUG ON CONTROLLER, PERFORMED SYS TEST IAW AMM 21-30-00 AND ALL INDICATIONS NORMAL. PERFORMED SATISFACTORY MX CHECK FLIGHT, ACFT RTS.