System Description

SYSTEM DIAGRAM

Courtesy of NISSAN

OUTLINE

BCM incorporates a power saving control function that reduces the power consumption according to the vehicle status.
BCM switches the status (control mode) by itself with the power saving control function. It performs the sleep request to each unit (IPDM E/R and combination meter) that operates with the ignition switch OFF. Normal mode (wake-up)
- CAN communication is normally performed with other units
- Each control with BCM is operating properly
CAN communication sleep mode (CAN sleep)
- CAN transmission is stopped
- Control with BCM only is operating
Low power consumption mode (BCM sleep)
- Low power consumption control is active
- CAN transmission is stopped

INPUT SIGNAL AND OUTPUT SIGNAL

Major signal transmission between each unit via communication lines is shown in the following table.

Component parts	Signal description
IPDM E/R	Each unit transmits the sleep-ready signal (ready) to BCM when all of the CAN sleep conditions are fulfilled. Each unit transmits the wake up signal to BCM when all of the CAN sleep conditions are fulfilled. Each unit receives the sleep wake up signal (sleep) from BCM via CAN communication. Each unit receives the sleep wake up signal (wake up) from BCM via CAN communication.
Combination meter
BCM	BCM transmits the sleep wake up signal (sleep) to each unit when all of the CAN sleep conditions are fulfilled. BCM transmits the sleep wake up signal (wake up) to each unit when all of the CAN sleep conditions are fulfilled. BCM receives the sleep-ready signal (ready) from each unit via CAN communication. BCM receives the wake up signal from each unit via CAN communication.

LOW POWER CONSUMPTION CONTROL WITH BCM

BCM reduces the power consumption with the following operation in the low power consumption mode:

The reading interval of the each switches changes from 10 ms interval to 60 ms interval.

Sleep mode activation

BCM receives the sleep-ready signal (ready) from IPDM E/R and combination meter via CAN communication.
BCM transmits the sleep wake up signal (sleep) to each unit when all of the CAN sleep conditions are fulfilled.
Each unit stops the transmission of CAN communication with the sleep wake up signal. BCM is in CAN communication sleep mode.
BCM is in the low power consumption mode and perform the low power consumption control when all of the BCM sleep conditions are fulfilled with CAN sleep condition.

Sleep condition

CAN sleep condition	BCM sleep condition
Receiving the sleep-ready signal (ready) from all units Ignition switch: OFF Vehicle security system alarm and panic alarm: No operation Warning lamp: No operation Intelligent Key warning buzzer: No operation Trunk lamp switch status: No change Stop lamp switch: OFF Turn signal indicator lamp: No operation Exterior lamp: OFF Door lock status: No change CONSULT communication status: No communication Meter display signal: Non-transmission Door switch status: No change Rear window defogger: OFF	Interior room lamp battery saver: Time out RAP system: OFF Power window switch LIN communication: No transmission Push-button ignition switch illumination: OFF NATS: No operation Remote keyless entry receiver communication status: No communication TPMS system: Stop

CAN sleep condition

BCM sleep condition

Wake-up operation

BCM transmits the sleep wake up signal (wake up) to each unit when any of the CAN wake-up conditions is fulfilled. It changes from the low power consumption mode or the CAN communication sleep mode to the normal mode.
Each unit starts the transmission of CAN communication with the sleep wake up signal. In addition, the combination meter transmits the wake up signal to BCM via CAN communication to report the CAN communication start.

Wake-up condition

BCM wake-up condition	CAN wake-up condition
Door unlock sensor: OFF→ON, ON→OFF Front door lock assembly LH: Lock or unlock Door lock switch: OFF→ON Door unlock switch: OFF→ON Trunk lid opener switch: OFF→ON Power window LIN communication: Receiving Remote keyless entry receiver: Receiving valid key fob	Receiving the sleep-ready signal (Not-ready) from any units Ignition switch: OFF→ON Hazard switch: OFF→ON PASSING switch: OFF→ON, ON→OFF TAIL LAMP switch: OFF→ON Front door switch LH: OFF→ON, ON→OFF Front door switch RH: OFF → ON, ON → OFF Trunk lamp switch: OFF→ON, ON→OFF Front door request switch LH: OFF→ON Front door request switch RH: OFF→ON Trunk opener request switch: OFF→ON Stop lamp switch signal: ON Remote keyless entry receiver: Receiving valid key fob

BCM wake-up condition

CAN wake-up condition