As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE NR 2 WILL NOT GO ONLINE. REPLACED RIGHT GCB C903 PER AMM. UNIT INSTALLED IS MR24227-397 OFF -384 ON. ENGINE NR 2 WILL GO ONLINE. IF RIGHT GENERATOR IS SELECTED OFF RIGHT GENERATOR STAYS POWERED. SUSPECT RIGHT GENERATOR CONTROL SWITCH ON P5 PANEL FAULTING. NO EICAS MSG'S DISPLAYED. REPLACED RIGHT GEN CONTROL SWITCH ON P5 PANEL. OPERATED ENGINES; RIGHT GENERATOR WILL NOW FOLLOW COMMANDED SWITCH POSITION.