As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: DURING OPERATIONAL TEST OF EMERGENCY LIGHTS, FOUND FAULTY LIGHTS FROM 26 TO 33, LEFT HAND SIDE NOT WORKING. REPLACED RIGHT AFT BATTERY PACK (AALA202105219007) AND FOUND LOOSE P2 CONNECTOR AT 31A SIDEWALL. ALL OPERATIONS CHECKS OK PER AMM 33-51-06.