April 5, 2026: LEMON Manuals is launched! Read the announcement.

System Diagram

Fig 1: Identifying Smart Key System Diagram (For Entry Function) (1 Of 2)

GTY221864

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Fig 2: Identifying Smart Key System Diagram (For Entry Function) (2 Of 2)

GTY215921

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

COMMUNICATION TABLE

Sender	Receiver	Signal	Line
Main Body ECU	Certification ECU	Front door courtesy light switch LH signal Front door courtesy light switch RH signal Rear door courtesy light switch LH signal Rear door courtesy light switch RH signal Back door courtesy light switch signal Steering wheel location information (vehicle type) signal Door lock position signal Back door control switch signal	CAN
Power Management Control ECU	Certification ECU	IG signal ACC signal Engine switch signal	LIN
Combination Meter Assembly	Certification ECU Main Body ECU	Vehicle speed signal	CAN
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	Matching request random number signal	LIN
Certification ECU	Combination Meter Assembly	Inside key existence warning signal Low key battery warning signal Shift position warning signal Meter buzzer request signal Door open indicate signal Steering lock warning signal	CAN
Certification ECU	Main Body ECU	Entry door lock signal Entry door unlock signal Door lock/unlock standby control signal Wireless door lock buzzer sound signal	CAN
Certification ECU	Power Management Control ECU	Immobilizer ID entry required signal Key code check signal	LIN
Certification ECU	ID Code Box	Replay ID code signal	LIN
Multiplex Network Door ECU (Back Door P/W)	Main Body ECU	Back door control switch signal	LIN