As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
JUST PRIOR TO DEPLETING CENTER TANK, THE RT MAIN TANK INDICATION DROPPED TO 7.24. FUEL USED AND FUEL FLOWS WERE VIRTUALLY EQUAL BETWEEN LT AND RT ENGINES. WHEN CENTER PUMPS WERE SHUTDOWN THE RT INDICATION RETURNED TO 8.53 AND HAS OPERATED NORMALLY SINCE THEN. ACFT GROUNDED. ACCOMPLISHED FQIS BITE TEST AND FOUND FAULT MESSAGE 28-41389, PROCESSOR FAILED. R & R FUEL QTY PROCESSOR UNIT AND OPS CHECKED GOOD REF AMM 28-41-81.