As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TYS - A/C WAS EN ROUTE FROM CLE TO GSP WHEN CREW GOT A CAUTION LIGHT OF THE BACKUP BATTERY OFF BUS. A/C DIVERTED INTO TYS WHERE MAINTENANCE REMOVED AND REPLACED THE BACKUP BATTERY CONTACTOR IAW EMB 145AMM 24-36-02. OPS CHECK GOOD AND WAS RELEASED LOG PAGE 2795170.