As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE PERFORMING T/C 78233001 ALL MID-CABIN AND FWD GALLEY EMERGENCY LIGHT BATTERY PACKS FAILED THE DEEP CYCLE TEST. TOTAL OF 6 BATTERY PACKS. GROUNDED - YES. REMOVED AND REPLACED FWD GALLEY AND ALL MID-CABIN BATTERY PACKS, REF WDM 33-51-12 THRU 33-51-21 AND AMM 33-51-06. PERFORMED T/C 78233001. ALL EMERGENCY LIGHTS AND BATTERY PACKS PASSED THE TEST.