As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON RIGHT ENGINE START UP HAD FOLLOWING ELECTRICAL SYSTEM INDICATIONS RT AC BUSS OFF EICAS ON OVERHEAD R BUS TIE ISLN RBUS OFF AND RT GENERATOR CONTROL OFF. BIT BPCU FAULT WAS DP TRIP MAIN BUSS/OVERLAP ZONE. REPLACED BPCU AND RT GCU. RAN ENG NO HELP. REINSTALLED ORIGINALS. SAME MSG ON NEW BPCU. CLEARED FAULTS. FOUND RT ENG GENERATOR FEEDER LEADS PHASE A AND B SWAPPED. SWAPPED LEADS AND RAN ENG. OPS NML NO MSGS.