Touch Select 2-4 Switch
WARNING: This page is about a different car, the 2002 Toyota Tundra and 2001 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
Touch select 2-4 switch sends a request signal to the 4WD control ECU, which activates the corresponding actuator(s). This switch is part of the integration and control panel, located in the front of the floor console.