System Diagram

WARNING: This page is about a different car, the 2008 Scion xB. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: CAN Communication System Diagram (1 Of 2)

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Fig 2: CAN Communication System Diagram (2 Of 2)

HINT:

The ABS and traction actuator (skid control ECU) detects and stores steering sensor and yaw rate sensor DTCs and performs DTC communication by receiving information from the steering sensor and yaw rate sensor.
The power steering ECU and the center airbag sensor assembly uses the conventional communication line (SIL) to perform DTC communication