What was found
FLIGHT 2186. ON TAKEOFF ROLL AT APPROX 30-40 KNOTS, EICAS PAX AFT DOOR OPEN. TAKEOFF REJECTED. CLEARED DURING TAXI TO GATE. REMOVED FROM SERVICE & PLACED ON MEL 52-70-00A. AFT PAX DOOR & NOTICED IND WENT FROM GREEN TO YELLOW BOX WITH BLACK X. INSPD & FOUND BREAK IN WIRE OF AFT PAX DOOR LOCK HARNESS AT DOOR SIDE OF HINGE FOR PINS C OF CONNECTERS P1 & P2. REPLACED AFT PAX DOOR LOCKED SENSOR HARNESS IAW MM 52-72-21-000-801-A, PARAGS 8I - 8L, & 52-72-21-400-801-A PARAGS 8A - 8G IAW FIM 52-72-00-810-804-A. AFT PAX DOOR NOW INDICATES NORMAL WHEN CLOSED & LOCKED OR FULLY OPEN. THIS MAINT ACTION CLEARS MEL 52-70-00(A) & PLACARDS REMOVED FROM CENTER CONSOLE IN FLIGHT DECK & ACFT MAINT LOG BOOK. RETURNED TO SERVICE.