FixVault

System Diagram

WARNING: This page is about a different car, the 2008 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Power Door Lock Control System Diagram
G05161024Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Communication table: 

COMMUNICATION TABLE

Sender Receiver Signal Line
ECM Main Body ECU Park/Neutral Position Switch CAN