As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BTB ETOPS SIGNIFICANT SYSTEM - RIGHT AFTER ENGINE START AND BEFORE COMMENCING TAXI RECEIVED EICAS AMBER MESSAGE -UNABLE RNP- FOLLOWED SHORTLY BY EICAS AMBER MESSAGE -L GPS- CHECK POS PAGE 3, CONFIRMED GPS FUNCTION WAS SWITCHED ON; NO GPS POSITIONS SHOWN. RESEATED C/B NO HELP, BITE L-MMR AND CKD NO FAULTS RESEATED BOX AND CKD OK FOR SERVICE PER AMM 34-58-00.