As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ENGINE VIBRATION INDICATIONS WENT BLANK ON SECONDARY ENGINE DISPLAY. USING TROUBLESHOOTING INFORMATION FROM THE FIM, THE AIRBORNE VIBRATION MONITORING SIGNAL CONDITIONER WAS FOUND INOPERATIVE. REPLACED THE AVM SIGNAL CONDITIONER AND ENGINE VIBRATION INDICATIONS WERE DISPLAYED CORRECTLY.