As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI STEERING TILLER BECAME DIFFICULT TO TURN. NOSE WHEEL WAS UNCONTROLLABLE. HYD PUMP RAN NORMALLY WHEN DEPRESSED AND HYD WAS OK. AFTER EXCERSIZING TILLER IT BEGAN WORKING FOR A SHORT TIME. REMOVED AND REPLACED NOSE WHEEL STEERING SERVO ACTUATOR IAW 32-50-25. OPS CHECK GOOD. (M)