As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT IN BASE MAINTENANCE: PERFORMED OPERATIONAL TEST OF THE EMERGENCY LIGHTS PER TASK CARD 26L00005062 AND MAINTENANCE MESSAGE BAT/ESPUSU (15WL) ATA 335100 POPS UP. TROUBLESHOOT FAULT IAW TSM. REMOVED AND REPLACED EMERGENCY POWER SUPPLY UNIT BATTERIES PER AMM 33-51-38 AND TASK CARD 26L0005062.