System Diagram

Fig 1: Engine Immobilizer System Diagram

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COMMUNICATION TABLE

Transmitting ECU (Transmitter)	Receiving ECU (Receiver)	Signal	Communication Method
Certification ECU (smart key ECU assembly)	Main body ECU	Engine immobilizer system set/unset signal Engine start signal Transponder valid signal Steering unlock demand signal Steering lock demand signal	LIN
Main body ECU	Certification ECU (smart key ECU assembly)	Key code recognition signal Engine start operation signal ACC relay activation signal IG relay activation signal
ID code box (immobilizer code ECU)	Certification ECU (smart key 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 (immobilizer code ECU)	Steering lock ECU	Steering lock release signal Matching request random number signal
Steering lock ECU	Certification ECU (smart key ECU)	L code verification signal