What was found
THE 'FUEL PUMP LT AFT' EICAS MSG DISPLAYED AND LOW PRESS LIGHT ON THE SW. FOUND NO POWER AT PUMP CONNECTOR ON PIN 4 (PHASE B1) SUSPECT RELAY K28123 INOP. REPLACED RELAY K28123 NO HELP. FOUND C PHASE SHORTED TO GROUND, SUSPECT WIRING OR PUMP. T-S BY REMOVING K28123 & CK DK28123 PIN B1 TO PUMP(DM28102) PIN 4 FOR OPEN OR SHORT. POSS BAD CONN DM28102. CHECKED FOR 115 VAC AT DM2 8102 PINS 2,4,6. FOUND NO DISCREPANCIES, SUSPECT L AFT FUEL BOOST PUMP. REPLACED LT MAIN TANK FUEL BOOST PUMP HOUSING. AFTER LEAK AND OPERATIONAL CHECK, NO LEAKS NOTED, OPS GOOD, NO EICAS MESSAGE.