As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED, ON TAKEOFF RECEIVED A BRAKE OVERTEMP MESSAGE ON THE EICAS. THE CREW DECLARED AN EMERGENCY AND RETURNED TO FIELD. THE AIRCRAFT LANDED WITHOUT INCIDENT. FIRE RESCUE USED THERMAL IMAGING TO DETERMINE THE BRAKE TEMPERATURES AND IT WAS DETERMINED THAT THE AIRCRAFT WAS SAFE FOR TAXI TO THE GATE. MAINTENANCE FOUND TO LEFT OUTBOARD BRAKE TEMPERATURE SENSOR TO BE ERRATIC. THE ITEM WAS DEFERRED. THE DEFERRAL WAS CLEARED ON 10/03/2012 WHEN MAINTENANCE REPLACED THE NUMBER 1 BRAKE TEMPERATURE INDICATION SENSOR. OPERATIONAL CHECKS WERE GOOD WITH NO FURTHER DEFECTS NOTED.