As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
L PACK OFF L PACK TEMP LIGHTS ILLUM W/ INOP AND PACK OFF LIGHTS ON TAXI OUT. REPLACED ACM INLET SENSOR, NO HELP WILL NOT RESET. REPLACED COMP OUTLET OVERHEAT SENSOR M555 L PACK CHECKS GOOD MFR 641137-1. ETOPS CATEGORY 'E': PROBLEMS WITH SYSTEMS CRITICAL TO ETOPS.