As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: GEAR DOORS WILL NOT OPEN USING GROUND OPERATION ARM AND OPEN SWITCHES. "ALT GEAR EXTEND" STATUS MESSAGE ON EICAS. REMOVED AND REPLACED GROUND OPERATION ARM OPEN SWITCHES. PER AMM32-00-40-860-802. OPERATIONAL CHECKED GOOD.