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System Diagram

Fig 1: Immobilizer System Diagram

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Communication table:

COMMUNICATION CHART

Transmitting ECU (Transmitter)	Receiving ECU (Receiver)	Signals	Communication method
Certification ECU	Front multiplex network door ECU LH Front multiplex network door ECU RH	Double lock fail-safe unset signal Security indicator light flash signal Security indicator light illumination signal Engine immobilizer system set/unset signal	LIN
Certification ECU	Main body ECU (driver side junction block)	Engine start signal Transponder valid signal Steering unlock demand signal Steering lock demand signal
Main body ECU (driver side junction block)	Certification ECU	Key code recognition signal Engine start operation signal ACC relay activation signal IG relay activation signal
ID code box	Certification ECU	Matching request random number signal EFI code reception signal Engine start permission demand reception signal S code verification result signal L code verification result signal Steering unlock demand reception signal Steering lock demand reception signal
ID code box	Steering lock ECU	Steering lock release signal Matching request random number signal
Steering lock ECU	Certification ECU	L code verification signal