i know this is a little old but, the solenoid should only have power when the trans control unit sends power to activate the solenoid. there is also a switch mounted on the column that is a two position one is for 1st gear only high speed lockout and the other turns on the ( auto ) feature by allowing the computer to send signal based on the speed sensor input. you defiantly have a wiring issue if your trans controller is new. the wire schematics are a little lacking as is the service manual on how the system functions.