As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FUEL IMBALANCE AMBER CAS: IN CRUISE AT FL 400 LEFT TANK WAS 440 LBS LOWER THAN RIGHT. FUEL FLOWS WERE SAME. CROSSFED RIGHT TO LEFT TO BALANCE TANK. TOOK CROSSFEED OFF AND THEN FUEL WAS ONLY. IRNING OUT OF RIGHT TANK. IT GOT TO 300 INBALANCE AND I CROSSFED AGAIN TO BALANCE IT AGAIN. CORRECTIVE ACTION: REPLACED FUEL PROBE. OPS CHECK GOOD. IAW 680A AMM 28-40-25.