As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON WALKAROUND FOR EMERGENCY LIGHT CHECK, FOUND LIGHTS OUT AT SEATS 20C AND 23C, AND L/H AFT OVERWING EMERGENCY EXIT LIGHTS. GROUNDED - YES. REMOVED AND REPLACED BATTERY PACK OF M1670 REF B737-800 AMM 33-51-06-960-805. EMERGENCY LT OPS AT 20C, 23C, AND L/H AFT OVERWING EXIT NOW CHECK GOOD. ALL EMERGENCY LT'S OP CHECK GOOD.