As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN THE DESCENT THE CABIN EMERGENCY LIGHTS BEGAN FLASHING AND CONTINUED TO FLASH UNTIL WE TURNED THE SWITCH OFF AFTER LANDING. CORRECTIVE ACTION: PERFORMED OPS CHECKS AND ALL LIGHTS WORKED NORMALLY ON GROUND. CUSTOMER REQUESTED REPLACEMENT OF EMER BATTERY. GAINED ACCESS TO BOTH BATTERIES, REPLACED BOTH BATTERIES WITH CUSTOMER SUPPLIED UNITS. OPS CHECKS SATISFACTORY. WORK DONE REF TO AMM 33-52-01