As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING COMPLETION OF ADS-B MOD LINE IT WAS DISCOVERED THAT SEVERAL INSIDE AND OUTSIDE EMERGENCY LIGHTS DID NOT ILLUMINATE. MX REMOVED AND REPLACED #2 AND #4 EMERGENCY LIGHT BATTERIES WITH OPERATIONAL CHECKS GOOD. A/C WAS APPROVED FOR RETURN TO SERVICE.