What was found
FIRE LOOP B, FAULT DISPLAYED ON UPPER ECAM SCREEN. REPLACED NR 2 FDU. INTERMITTENT FAULT. CHECKED AND CLEANED FAN AND CORE LOOPS. REPOSITIONED MULTIPLE POINTS OF LOOP CONTACTING STRUCTURE. FOUND CORE LOOP CONNECTOR LOOSE. AS PRECAUTION, REPLACED CORE LOOP, RE MM26-12-34. ENGINE IDLE RUN OK.