What was found
ACFT WAS LOADED WITH 30.1 FUEL, SHORTLY AFTER T/O GOT ECAM ALERT, BOTH CTR FUEL TANKS FAULT- DIRECTED US TO TURN OFF BOTH CTR FUEL PUMPS. TOTAL FUEL DROPPED TO 17.0 AND LT OUTER TANK INDICATED 2.1. TURNED BACK TO DEPARTURE, LOWEST FUEL TOTAL WAS 15- WITH A DASH FOR A DIGIT AND LOWEST LT OUTER TANK 1.6-WITH A DASH. CRASH TRUCKS SAID NO FUEL LEAK. ON THE GROUND, BOTH DASHES IN TOTAL AND LAT TANK WENT AWAY AND FUEL QTY TOTAL JUMPED TO 20.0- LT OUTER TANK WENT FROM 1.6 TO 8.0 WITHOUT A DIGIT. WERE BELOW MAX LANDING WT WHEN LANDED. FAULT CODE SHOWN 321 LT OUTER COMP DRAINED TANK, CHECKED TANK CAP AND RESISTANCES FROM FQIC AND FROM TANK SPAR CONNECTORS ALL READINGS WITHIN LIMITS REF MM 28-42-00-5. MEGGED WIRING FROM FQIC TO SPAR CONNECTORS 563VC A AND 5073VC A NO FAULTS FOUND CHECKED EXCITATION VOLTAGE AT SPAR CONNECTORS FOUND OK. CHECKED RETURN VOLTAGE AT FQIC FOUND OK. TANK INDICATION IS NORMAL AND NO CURRENT FAULTS.