As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"RUDDER RATIO SNGL" EICAS MESSAGE. PERFORMED WIRING CHECK OF WIRING BETWEEN RUDDER RATIO ACTUATOR AND YSM PER IFIM TASK 27-21-00-810-844 AND WDM 27-21-31. NO FAULTS NOTED. RUDDER RATIO ACTUATOR REPLACED IAW B747 AMM 27-21-12/401, OPS CHECK GOOD. RUDDER RATIO L & R GROUND TEST GOOD IAW B747 AMM 27-21-00-720-810.