As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INITIALLY SHOWED A NR 800 LB DIFFERENCE IN FUEL QUANTITY BETWEEN THE FUEL TOTALIZER AND THE FMC FUEL QUANTITY. THE LT, RT, AND CENTER QUANTITY ADDED UP TO EQUAL THE FUEL TOTALIZER QUANTITY OF 18.4. HOWEVER THE FMC ACTUAL FUEL SHOWED 17.6. ACFT GROUNDED. CYCLED PWR FOR CMU IAW MM 23-27-33 NO HISTORY, OPS NORMAL.