As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 415 BOS-SAN, HAD AN AIR RETURN TO BOSTON DUE TO CENTER TANK PUMP 1 FAILED AFTER SLAT RETRACTED. PERFORMED OPS CHECK OF NR 1 CENTER TANK PUMP PER AMM 28-21-51. OPS CHECK NORMAL. SUSPECT IMPROPER CONFIGURATION OF AIRCRAFT DUE TO MEL 28-21-02 CONDITION 1 BEING APPLIED TO THE NR 2 CENTER TANK PUMP.