As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATB TO ATL DUE TO A RIGHT ENGINE EEC CONTROL MESSAGE. MTC FOUND FADEC FAULT 155-23 FMV DISAGREE ON RIGHT EEC. CREW CONTACTED DISPATCH AND MC AND DECISION WAS MADE TO RETURN TO ATL. MTC REPLACED EEC AND HMU. PERFORMED ENGINE RUNS WITH NO FAULTS. A/C RTS.