Circuit Description
WARNING: This page is about a different car, the 2005 Toyota Sienna. However, it is still accessible from the selected car via links, so may be relevant.
The un-lock warning switch turns ON when the key is inserted in the ignition key cylinder. The courtesy lamp switch turns ON when the driver side door is opened. These 2 switches are monitored by the body ECU. In order to prevent the key from being locked in, the body ECU controls door locking operation according to the conditions of these switches so that the doors are not locked.