Power Source Mode does not Change to ON (IG): Description
WARNING: This page is about a different car, the 2008 Lexus IS 350. However, it is still accessible from the selected car via links, so may be relevant.
When the engine switch is pushed with the electrical key in the cabin, the power source control ECU receives signals to switch the power source mode.
HINT:
To allow use of Techstream to inspect the smart access system with push-button start when the engine switch is off, repeat opening and closing any of the doors. Opening and closing a door establishes communication between Techstream and the power source control ECU. (Opening and closing a door can also be simulated by operating a door courtesy light switch.)