System Diagram

WARNING: This page is about a different car, the 2006 Lexus IS 350 and 2006 Lexus IS 250. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Identifying Pre-Collision System Diagram

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Communication table:

COMMUNICATION TABLE

Sender ECU	Receiver	Signal	Line
Distance Control ECU	Seat Belt Control ECU	Relative vehicle speed signal Vehicle-to-vehicle distance signal Seat belt operation signal	CAN
Skid Control ECU	Seat Belt Control ECU	Seat belt operation signal Sudden braking signal VSC control signal	CAN
Center Airbag Sensor Assembly	Seat Belt Control ECU	Buckle switch malfunction signal Driver seat belt buckle switch signal	CAN
Seat Belt Control ECU	Combination Meter	Pre-collision safety malfunction signal	CAN - BEAN
Distance Control ECU	Skid Control ECU	Brake assist standby signal	CAN