As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY LIGHTING: WHILE EXECUTING THE POWER ON CHECKLIST, WE DISCOVERED THE EMER LIGHTS WILL NOT ILLUMINATE IN THE ARM POSITION, BUT SOME WILL ILLUMINATE IN THE ON POSITION. REMOVED AND REPLACED ALL 4 EMERGENCY BATTIERES IAW MM 33-50-10.