What was found
APU RELIABILITY COLD START UNSUCCESSFUL ON FLT ILN-PDX AFTER 3 START ATTEMPTS. STATUS MSG APU DOOR. NOTED BY MX. MULTIPLE APU STARTS ON GND NORMAL, 1ST ATTEMPT. APU INLET DOOR ACTUATOR CONNECTOR PLUG CLEAN & DRY, MOISTURE & FROST NOTED ON EMPENAGE. DMI 145628 REMAINS OPEN. REF AMM 49-11-00-802-002. APU DOOR INOP, LOCKED OPEN, TRANSFERRED TO MDDR 145716 PER MEL 49-15-01-01A, CAT C, REMOVED AND REPLACED APU INLET DOOR RELAY IAW SWPM 20-81-22 PER ATLAS MCC REQUEST. OPS CHECK GOOD THIS DMI REMAINS OPEN PER MCC REQUEST. REMOVED AND REPLACED APU INLET DOOR OPEN RELAY K547 IAW SWPM 20-81-22 IAW MCC REQUEST. PERFORMED APU OPS TEST IAW 49-11-00. OPS CHECK GOOD. APU DOOR INTAKE LOCKED OUT TO OPEN POSITION. REACTIVATED APU AIR INTAKE DOR ACTUATION SYSTEM IAW AMM 49-00-00. PERFORMED APU AIR INTAKE SYSTEM TEST IAW AMM 49-15-00, OPS CHECK GOOD. APU AIR INTAKE DOOR OPENED & CLOSED NORMAL. NO FURTHER DEFECTS NOTED.