As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED COACH INTERIOR EMERGENCY LIGHTS ARE ON INFLIGHT WITH THE CONTROL SWITCHES OFF AND NO EICAS MESSAGE. CYCLED BOTH COCKPIT SWITCH AND AFT F/A SWITCH TO TRY TO EXTINGUISH, NO HELP. REPLACED POWER SUPPLY M10818 AND BATTERY PACKS AT M10818, M10817AND M10770. TESTED INPUT VOLTAGE TO ABOVE POWER SUPPLIES, ON SIGNAL AND OFF SIGNAL. FOUND ALL OK. LIGHT OPS TEST AND SYS TEST OK.