As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TROUBLESHOOTING THE FUEL CONFIG LIGHT PROBLEM THE LT OR RT TANK SHOWED NO TRANSFER WITH BOOST PUMP PRESSURE ON. AFTER DEFUELING RT & CTR TANK & NO PUMP PRESSURE FOUND LT TANK MOVING FUEL TO CTR WITH LT DEFUEL VLV OPEN. POSSIBLE LT TANK SUCTION CHECK VLV RELEASING FUEL INTO THE FEED MANIFOLD. REPLACED LT MAIN TANK FUEL BOOST PUMP BYPASS VLV SUCTION CHECK VALVE IAW AMM 28-22-04.