As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE FLIGHT CREW REPORTED RECEIVING AN ENGINE CONTROL FAULT DURING START-UP WITH THE LEFT ENGINE. THE MAINTENANCE VENDOR TROUBLESHOT AND DOWNLOADED THE ENGINE COMPUTER AND DETERMINED AN OVERSPEED CIRCUIT FAULT. THE FUEL CONTROL UNIT WAS REMOVED AND AN OVERHAULED FCU WAS INSTALLED. FAULT CLEARED. COMPLETED GROUND RUNS AND LEAK CHECKS WITH NO DEFECTS. THE AIRCRAFT WAS RETURNED TO SERVICE