As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI AFTER ENGINE START " RUDDER RATIO" EICAS MESSAGE DISPLAYED.A/C RETURNED TO GATE (BTB) AND MTX GROUNDED A/C MTX THEN COMPLIED WITH FIM-21-27 FT804, NO FAULTS NOTED AT THIS TIME, OPS TEST OF RUDDER AND RUDDER TRIM CONTROL SYSTEM GOOD IAW AMM.27-21-00 NO FAULTS NOTRD AT THIS TIME. MTX RETURNED A/C TO SERVICE