As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYS - PRIOR TO ENG START W/"L PAC" SWITCH IN OFF POS THE PAC IND LIGHTS (L PAC OFF) ON THE O/H AND EICAS DID NOT ILLUMINATE. CYCLED SWITCH SEVERAL TIMES TO OBTAIN PROPER INDICATION. REMOVED AND REPLACED LT PACK FLOW CONTROL CARD ASSY IAW AMM 21-51-09. OPS CHECK GOOD. NO DEFECTS NOTED.