What was found
ETOPS - BTB FUEL APU LP VALVE FAULT. REMOVED AND REPLACED APU LP VALVE ACTUATOR PER AMM 28-29-52. OPS CHECK GOOD. SECURITY CHECK GOOD. BTB AGAIN FOR SAME ISSUE. REMOVED AND REPLACED RELAY 6QF, NO CHANGE FAULT STILL ACTIVE AT SHUT DOWN.ECB RERACKED, FAULT CONTINUES, APU ISO VALVE STILL SHOWING OPEN WHEN SUPPOSED TO BE CLOSED. REMOVED AND REPLACED RELAY 6QF PER TSM 28-29-00 OPS CHECKED GOOD NO FAULTS NOTED OK FOR SERVICE.