As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING ASA TASK CARD 78233001, 2X EMERGENCY LIGHT BAT PACKS FAIL FUNCTION CHECK. GROUNDED - YES. REMOVED AND REPLACED EMERGENCY LT POWER SUPPLY AND BATT PACK IAW B737-800 AMM 33-51-06-960-806 X2. BOTH NOW PASS FUNCTIONAL CHECK.