As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER CENTER PUMPS WERE TURNED OFF, LEFT TANK INDICATION DROPPED ABOUT 1100LBS AND IMBAL CAUTION LIGHT ILLUMINATED. RAN IMBAL QRH, NO LEAKS SUSPECTED (FUEL USED PLUS FUEL REMAINING EQUALED DEPARTURE FUEL) IMBALANCE GRADUALLY REDUCED TO 600LBS (LEFT LOW) AT LANDING. GROUNDED - YES. ACCOMPLISHED FQIS BITE REF B737-900 AMM 28-41 TASK 801. NO HISTORY FOR PAST 120 DAYS OK FOR SERVICE.