As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ACCOMPLISHING TASK CARD 78233008 (EMERG LIGHTS OPS CHECK) FOUND AFT RT SERVICE DOOR EMERG EXIT SIGNS BOTH DOOR & ADJACENT TO GALLEY AND EXTERIOR LIGHT INOP. PULLED AND COLLARED R AFT BREAKER. REMOVED AND REPLACED AFT RT POWER SUPPLY/BATTERY PACK. RESET R AFT BREAKER. ALL LIGHTS OPS CHECK GOOD. REF AMM 33 51 06 960 806.