As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT PACK OFF LIGHT & LT PACK OFF EICAS MESSAGE NEVER ILLUMINATED WHEN PACK SELECTOR IN OFF POSITION. PERFORMED BITE CHECK ON LT PACK CONTROLLER NO FAULTS NOTED. TRIED TO DUPLICATE PROBLEM NUMEROUS TIMES. OPS CHECKED OK IAW AMM21-51-00-705-001.