What was found
FLIGHT ADVISED FLIGHT DISPATCH THAT THEY HAD A BRAKE TEMPERATURE INDICATION PROBLEM, AND THE WERE RETURNING BACK TO STATION. JUST AFTER LIFTOFF HAD A ECAM BRAKE HOT. NR 1 BRAKE TEMP INCREASED TO 1,000 DEGREES C. GEAR SELECTED DOWN WITH NO EFFECT. EVENTUALY COOLED TO 300+ DEGREE C THAN ROSE AGAIN TO 450 DEGREE C. CREW DECLARED AN EMERGENCY WITH ATC, AND THE ACFT LANDED OVERWEIGHT. FOUND THE NR 1 BRAKE TEMP SENSOR INOP. FIX: BSCU REPLACED. NR1 BRAKE TEMP SENSOR REPLACED IAW AMM 32-00-00. CKD SERV, THE FOLLOWING PARTS HAVE BEEN IDENTIFIED. BRAKE TEMP SENSOR: MPN C20229001, BSCU PN C202163392E34, SN 378.