What was found
AIRCRAFT WAS GROUNDED: AN INTERMITTENT PRESSURIZATION LIGHT ON 4R DOOR, TRIGGERED OVER PRESSURE INDICATION ON 4R DOOR EACH TIME IT SHOWED UNARMED IN THE FLIGHT DECK (INDICATING AS IT SHOULD CABIN PRESSURIZED). EACH TIME FLIGHT ATTENDENT JIGGLED THE ARMED HANDLE THE ARMED INDICATION IN THE FLIGHT DECK WOULD ILLUMINATE AND THE OVER PRESSURE INDICATION ON THE 4R DOOR WOULD STOP. CABIN PRESSURE REMAINED STEADY AT ALL TIMES. MAINTENANCE REPLACED PROXIMITY SENSOR 7WN2 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK PER AMM 52-71-11.