As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER ENGINE START, SWITCH SELECTED TO GROUND LT & RT UTILITY BUSS AND LT HYD SYSTEM PRESSURE EICAS MESSAGE. PERFORMED NR 2 ENGINE IDLE START PROCEDURES AND RUNS IAW AMM 72-00-00 OPS CHECKED GOOD, NO DEFECTS NOTED. REMOVED AND REPLACED C904 & BTB AS PRECAUTION. SYSTEM CHECKED NORMAL IAW MM 24-23-03.