What was found
AIRCRAFT WS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT DIVERTED TO SLC DUE TO A FUEL IMBALANCE WARNING, 2700LBS LOW IN LEFT WING TANK. FLIGHT CREW FOLLOWED QRH FOR BALANCING. UPON BALANCE, FUEL RETURNED TO LEFT WING, CAUSING AN IMBALANCE IN THE RIGHT WING. BALANCED AGAIN; ECAM SHOWED BOTH LEFT AND RIGHT OUTER TANKS UNUSABLE.THE AIRCRAFT LANDED SAFELY AT SLC WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE FUEL QUANITY INDICATION COMPUTER PER AMM 28-42-34 AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK.