Circuit Description
WARNING: This page is about a different car, the 2002 Lexus LX 470. However, it is still accessible from the selected car via links, so may be relevant.
When the ignition switch is turned to the ON position, battery positive voltage is applied to the terminal No. 13 (IG) of the wireless door lock ECU. See Fig 1. Furthermore, power supplied from the terminal No. 13 (IG) of the ECU is used as power for the wireless door lock buzzer.