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System Diagram

Fig 1: Smart Key System Diagram (1 Of 2)

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Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: Smart Key System Diagram (2 Of 2)

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Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Sender	Receiver	Signal	Line
Main body ECU	Certification ECU	Back door courtesy light switch signal	CAN
Main body ECU	ECM	IG signal ACC signal Inside illumination control signal for entry Door courtesy light switch signal (driver and passenger doors) Vehicle type handle signal	CAN
Certification ECU	Main body ECU	Back door lock signal Entry lock switch signal	CAN
Certification ECU	Main body ECU	Immobiliser ID entry required signal Key code check signal	CAN / LIN
Steering lock ECU	Certification ECU	Encryption code signal Encryption code finish signal Encryption calculate fixed number memory requirement signal During entry control signal	LIN
ID code box	Certification ECU	DTC (B2791) signal Matching request random number signal	LIN