What was found
LEFT CENTER FUEL PUMP "LOW PRESSURE" LIGHT ILLUMINATED WITH 1000 LBS OF FUEL IN CENTER TANK. BOTH PUMPS WERE OFF DURING CLIMB DUE TO LIGHT FUEL LOAD IN CENTER TANKS. WHEN WE TURNED THE FUEL PUMPS ON AT CRUISE, ONLY THE RIGHT PUMP TURNED ON. THE LEFT FUEL PUMP "LOW PRESSURE" LIGHT REMAINED ILLUMINATED. GROUNDED-YES. REMOVED AND REPLACED LEFT CENTER TANK FUEL PUMP, REF B737-900 AMM 28-22-41 STEPS A(1) - H 27. PERFORMED LEAK CHECK AND OPERATIONS CHECK ON LT CENTER FUEL PUMP ASSEMBLY. OPERATIONS CHECK GOOD, LEAK CHECK GOOD. NO FURTHER DEFECTS NOTED.