What was found
AFTER FLIGHT APU START FAILED DUE TO LOW OIL PRESSURE LIGHT. GROUNDED - YES. ETOPS OIL SYSTEM SERVICED. PERFORMED APU BITE. NO FAULTS IN CURRENT STATUS, FAULT AND MAINTENANCE HISTORIES IAW FIM 49-60 TASK 801. CHECKED APU OIL LEVEL AT APU, CHECKED FULL REF B737-900 MM 12-13-31. PERFORMED MAGNETIC DRAIN PLUG INSP, NO DEFECTS FOUND REF AMM 49-91-81. STARTED/RAN APU NUMEROUS TIMES, OPERATES NORMALLY. CHECKED/CLEANED LOW OIL PRESSURE SWITCH ELECTRICAL CONNECTOR REF AMM 49-11-01. RAN APU TWO MORE TIMES, OPERATES NORMALLY.