As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK, CLIMBING THRU FL 180, EXPERIENCED A LARGE SIGNIFICANT CONTROL BUMP --RT ELEVATOR IND PARTIALLY DOWN LT ELEVATOR INDICATED ON THE MARK AIRFRAME VIBRATION NOTED. DFDR REMOVED TO AVI FOR READ, C/W FIM 27-31-00 FIG 104 ELE POSITION INDICATION READINGS WITHIN LIMITS. CLEANED C/P ON POSITION INDICATOR. TROUBLESHOOTING IN PROGRESS.