What was found
(CAN) DURING CLIMB OUT PITCH TRIM CAUTION LIGHT ILLUMINATED, AUTO TRIM FAIL MESSAGE ON PFD & TRIM INDICATOR FULLY NOSE UP. FAULTS LOGGED IN CDS: 67,E7,63,E3,ED,EE. SPEED APPROX 185 KTS. FLT OPERATED MANUALLY. UNEVENTFUL APPROACH & LANDING. TROUBLESHOOTING REVEALED GIVEN FAULTS LOGGED IN CDS SUGGEST PITCH TRIM RUNAWAY & FULLY NOSE UP INDICATOR. ON ELEVATOR TRIM INDICATOR SHOWS THAT LEFT PITCH TRIM ACTUATOR FAILED. INSPECTION OF THIS, NO SUBSEQUENT FAULTS HAVE OCCURRED ON SYS & INCID. IS THEREFORE REGARDED AS ONE-TIME EVENT, PROBABLY CAUSED BY MOISTURE IN LVDT PLUG FOR LT PITCH TRIM UNIT OR PLUG ON FCECU FROM LT PITCH TRIM UNIT. A/C RETURNED TO SERVICE.