As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLT - ON CLIMBOUT FROM CLT, EN ROUTE TO CUN, CREW RECEIVED A NR 2 ENGINE DUAL FIRE LOOP FAULT (A & B LOOP) ON THE FIRE CONTROL PANEL. FLIGHT RETURNED TO FIELD AT CLT AND LANDED WITHOUT FURTHER INCIDENT. NO EMERGENCY WAS DECLARED. MAINTENANCE COULD NOT DUPLICATE FAULT. REMOVED AND REPLACED FIRE OVERHEAT MODULE AS A PRECAUTIONARY PER MM 26-10-01-404-002/004-002. OPERATIONAL TEST NORMAL.