As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY LIGHTS DO NOT COME ON IN WHEN SWITCH IS SELECTED TO THE "ON" POSITION. REMOVED DEFECTIVE #4 EMERGENCY BATTERY P/N:CBS28-1, S/N:1934M AND INSTALLED A CUSTOMER SUPPLIED REPAIRED EMERGENCY BATTERY P/N:CBS28-1, S/N:6000M. PERFORMED SATISFACTORY OPERATIONAL CHECK. WORK PERFORMED IN REF WITH AMM 33-50-05.