What was found
INSPECTION TYPE:NA DIVERSION, SUPPLEMENTAL SDR. NO EMERG DECLARED, ENG 2 LOOP B IN FLT PERF ECAM INSTRUCT (ENG & WING A/I ON) THEN SEVERAL INTERMIT ENG 2 LOOP ECAM MSG & NO ENG FIRE DET MSG. SWAPPED FD CONT UNITS (11WD &12WD T/S - NO FAULTS ON LOOP B DURING ENG RUN W/ A/I ON. SWAPPED ENG FCDU BACK TO ORIG POS. DEFRD MEL 26-12-01-1 AMM 26-12-11 & 26-12-00. REPLACED NR 2 ENGINE FIRE DETECTION UNIT IAW AMM 26-12-11-0401. OPS CK GOOD. PLACARD REMOVED.