What was found
(CAN) AIRCRAFT TOOK OFF NORMALLY, BUT WHEN THE LG WAS SELECTED UP, A GEAR DISAGREE CAUTION MSG WAS TRIGGERED, WITH ALL 3 GEARS STILL SHOWING DOWN & LOCKED. ACFT TURNED AROUND & THE LANDING WAS UNEVENTFUL. UPON INVESTIGATION, IT WAS DISCOVERED THAT THE LG CONTROL HANDLE CONNECTOR S125 HAD 1 WIRE NOT POSITIVELY LOCKED IN SOCKET 2E. UPON DISASSEMBLY, IT WAS DISCOVERED THAT THE WRONG PIN HAD BEEN INSTALLED ON THIS WIRE. THE PROPER TERMINATION WAS INSTALLED & THE ACFT WAS RETURNED TO SERVICE.