What was found
BOS FLT 312 EN-ROUTE, FLL TO BOS. WHILE THE FLIGHT WAS DESCENDING, AND GOING FROM FLAPS 10 TO FLAPS 15, THERE WAS A FLAP DISAGREEMENT. THE FLAPS INDICATED SPLIT BETWEEN 10 AND 15 DEGREES, BUT WITH NO ASSOCIATED ROLL. THE FLIGHT DID A GO-AROUND WHILE RETRACTING THE FLAPS TO 10 DEGREES PER THE CHECKLIST. FLIGHT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE TRAILING EDGE FLAP INDICATOR. OPERATIONALLY CHECKS OK.