What was found
CREW RETURNED TO THE FIELD FOR A STRONG ELECTRICAL ODOR COMING FROM THE VENTS LOCATED FROM BACK OF FIRST CLASS TO MIDDLE OF THE ACFT. NO ELECTRICAL SMELLS NOTED THROUGHOUT AIRCRAFT. RAN APU WITH PACKS ON & ALL RECIRC FANS OPERATING. NO LOAD SHED OF LAV/GALLEY FANS OR CARGO FWD EXHAUST FAN. FOLLOWED THE FIM DMC B787-A21-20-F5-72A-421A-A TO ITS ENTIRELY ,CHECK CABINS ,GALLEYS & LAVS, ALSO INSIDE THE CREW REST AREA , NO ODOR NOTED. LAVATORY/GALLEY FAN 1 THE LAV/GALLEY VENT FAN 1 FAILURE. OR LAV/GALLEY VENT FAN 1 FAILURE. THIS MESSAGE WILL BE INHIBITED BY A FAILURE OF RDC 7 UN LESS THE MESSAGE IS ACTIVE BEFORE RDC 7 FAILS. DB 24 BPCU GATEWAY OPS (RIGHT) DB 24 BPCU GATEWAY OPS (LEFT) UNIT, BUS POWER OFF 78-2422-9-0002 0954 ON 0000 UNIT, BUS POWER OFF 78-2422-9-0002 0954 ON 78-2422-9-0002 2548 FOUND MX MSG 24-19317 & 24-19351 IN PRESENT LEG FAULTS. BPCU OPS SHED GROUP 17 & 51 LOADS. REF FIM 24-40-F1-N4A-421A-A & 24-40-F1-R8A-421A-A NO MX ACTION NECESSARY. ALSO NOTED HISTORY OF MX MSG 24-12752. REF FIM 24-20-F8-56A-421A-A. REPLACED RT BPCU