As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT, EMERGENCY LIGHTS OVER THE DOORS AND THREE CENTER AISLE OVERHEAD LIGHTS BEGAN FLICKERING WITH THE SWITCH IN THE ARM POSITION. REMOVED FORWARD EMERGENCY BATTERY AND INSTALLED TESTED EMERGENCY BATTERY. REMOVED AFT EMERGENCY BATTERY AND INSTALLED NEW EMERGENCY BATTERY. OPS CHECKS GOOD. ALL WORK ACCOMPLISHED IAW AMM 33-52-01.