System Diagram

WARNING: This page is about a different car, the 2021 Nissan Rogue. However, it is still accessible from the selected car via links, so may be relevant.

Courtesy of NISSAN NORTH AMERICA, INC.

Component	Function
Door switch	Door switch detects door open/close condition and then transmits door switch signal to BCM.
IPDM E/R	IPDM E/R operates horns with horn request signal received from BCM. IPDM E/R operates headlamps with high beam request signal received from BCM via CAN communication.
BCM	BCM controls VEHICLE SECURITY SYSTEM. BCM transmits horn request signal intermittently to IPDM E/R via CAN communication. BCM transmits high beam request signal intermittently to IPDM E/R via CAN communication.
Push-button ignition switch	Push-button ignition switch has push switch inside which detects that push-button ignition switch is pressed, and then transmits the signal to Intelligent Key unit. Intelligent Key unit changes the ignition switch position with the operation of push-button ignition switch. Intelligent Key unit maintains the ignition switch position status while push-button ignition switch is not operated.
Intelligent Key	The Intelligent Key system is a system that makes it possible to lock and unlock the door locks (door lock/unlock function) by carrying the Intelligent Key, which operates based on the results of electronic ID verification using two-way communication between the Intelligent Key and the vehicle (Intelligent Key unit).
Outside key antenna	Outside key antenna detects whether Intelligent Key is within the detection area or not, and then transmits signal to Intelligent Key unit.
Door request switch	Door request switch transmits door lock/unlock request signal to Intelligent Key unit.
Hood switch	Refer to Hood Switch .
Horn	Theft warning alarm function activates horns intermittently when BCM detects that any door or hood is opened by unauthorized means, while the system is in the ARMED state. Panic alarm function activates horns intermittently when operating a cellular phone using the Telematics system function.
Intelligent Key unit	Intelligent Key unit performs the ID verification between Intelligent Key unit and Intelligent Key when the Intelligent Key is carried into the detection area of NATS antenna amp., and push-button ignition switch is pressed. If the ID verification result is OK, ignition switch operation is available.
TCU	TCU transmits panic alarm request signal to BCM when panic alarm request is received from Infiniti Connection ^TM date center.
Headlamp	Panic alarm function activates headlamps intermittently when operating a cellular phone using the Telematics system function.
Hands free sensor control unit	Hands free sensor control unit judges user operation by detecting the hands free sensor.
Hands free sensor	Hands free sensor detects when the user performs kick motion toward rear bumper.