What was found
POSSIBLE FUEL QTY INDICATION MALFUNCTION. FUEL CONFIGURATION EICAS MESSAGE DISPLAYED. FUEL DISAGREE PROG 2 ON FMC. AIR TURNBACK. PERFORMED FIM 28-41 FAULT TREE 847, WITH NO FAULT FOUND. INSPECTED AND CLEANED LEFT BUSS CONNECTOR, NO DEFECTS NOTED. REMOVED PROCESSOR AND CHECKED CONNECTOR WITH NO DEFECTS, REINSTALLED PROCESSOR. SUMP FUEL TANKS WITH NO EVIDENCE OF WATER. PERFORMED ENGINE RUN, BITE PROCESSOR AND NO FAULTS FOUND. MOVED FUEL VIA TRANSFER VALVES AND ALL OPS NORMAL. ALL OPS CHECK GOOD IAW AMM 28-41-00. OK FOR SERVICE.