Infiniti QX56 (Z62). Manual - part 970

PCS-36

< SYSTEM DESCRIPTION >

[POWER DISTRIBUTION SYSTEM]

COMPONENT PARTS

BCM compares following status comparing.
• Ignition relay-1 control signal, and power supply position judged by BCM
• Ignition relay (inside IPDM E/R) control request, and Ignition relay (inside IPDM E/R) status

Accessory Relay

INFOID:0000000006220193

BCM turns ON the accessory relays to supply accessory power supply or ignition switch ACC signal to each
ECU when the ignition switch is turned ACC or ON.
BCM compares status of accessory relay control signal, and power supply position judged by BCM.

Blower Relay

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BCM turns ON the following relays to supply ignition power supply or ignition switch ON signal to each ECU
when the ignition switch is turned ON.
• Ignition relay-1
• Ignition relay (inside IPDM E/R)
• Blower relay
BCM compares status of blower relay control signal, and power supply position judged by BCM.

Push-Button Ignition Switch

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BCM transmits the change in the power supply position with the push-button ignition switch to IPDM E/R via
CAN communication line. IPDM E/R transmits the power supply position status via CAN communication line to
BCM.

PCS

SYSTEM

PCS-37

< SYSTEM DESCRIPTION >

[POWER DISTRIBUTION SYSTEM]

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SYSTEM

POWER DISTRIBUTION SYSTEM

POWER DISTRIBUTION SYSTEM : System Diagram

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POWER DISTRIBUTION SYSTEM : System Description

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SYSTEM DESCRIPTION

• PDS (POWER DISTRIBUTION SYSTEM) is the system that BCM controls with the operation of the push-

button ignition switch and performs the power distribution to each power circuit. This system is used instead
of the mechanical power supply changing mechanism with the operation of the conventional key cylinder.

• The push-button ignition switch can be operated when Intelligent Key is in the following condition. Refer to

Engine Start Function for details.

- Intelligent Key is in the detection area of the inside key antenna.
- Intelligent Key backside is contacted to push-button ignition switch.
• The push-button ignition switch operation is input to BCM as a signal. BCM changes the power supply posi-

tion according to the status and operates the following relays to supply power to each power circuit.

- Ignition relay (inside IPDM E/R)
- Ignition relay-1
- ACC relay
- Blower relay

NOTE:
The engine switch operation changes due to the conditions of brake pedal, selector lever and vehicle speed.

• The power supply position can be confirmed with the lighting of the indicators near the push-button ignition

switch.

BATTERY SAVER SYSTEM

When all the following conditions are met for 60 minutes, the battery saver system will cut off the power supply
to prevent battery discharge.
• The ignition switch is in the ACC position
• All doors are closed
• Selector lever is in the P position

Reset Condition of Battery Saver System

In order to prevent the battery from discharging, the battery saver system will cut off the power supply when all
doors are closed, the selector lever is on P position and the ignition switch is left on ACC position for 1 hour. If
any of the following conditions are met the battery saver system is released and the steering will change auto-
matically to lock position from OFF position.
• Opening any door
• Operating with door request switch on door lock
• Operating with Intelligent Key on door lock
Press push-button ignition switch and ignition switch will change to ACC position from OFF position.

JMMIA0444GB

PCS-38

< SYSTEM DESCRIPTION >

[POWER DISTRIBUTION SYSTEM]

SYSTEM

STEERING LOCK OPERATION

Steering is locked by steering lock unit when ignition switch is in the OFF position, selector lever is in the P
position and any of the following conditions are met.
• Opening door
• Closing door
• Door is locked with door request switch
• Door is locked with Intelligent Key

POWER SUPPLY POSITION CHANGE TABLE BY PUSH-BUTTON IGNITION SWITCH OPERA-
TION

The power supply position changing operation can be performed with the following operations.
NOTE:
• When an Intelligent Key is within the detection area of inside key antenna and when Intelligent Key backside

is contacted to push-button ignition switch, it is equivalent to the operations below.

• When starting the engine, the BCM monitors under the engine start conditions,
- Brake pedal operating condition
- Selector lever position
- Vehicle speed

Vehicle speed: less than 4 km/h (2.5 MPH)

Vehicle speed: 4 km/h (2.5 MPH) or more

Emergency stop operation

• Press and hold the push-button ignition switch for 2 seconds or more.

• Press the push-button ignition switch 3 times or more within 1.5 seconds.

Power supply position

Engine start/stop condition

Push-button ignition switch 

operation frequency

Selector lever position

Brake pedal operation condition

LOCK 

→

 ACC

—

Not depressed

1

LOCK 

→

 ACC 

→

 ON

—

Not depressed

2

LOCK 

→

 ACC 

→

 ON 

→

 

OFF

—

Not depressed

3

LOCK 

→

 START

ACC 

→

 START

ON 

→

 START

P or N position

Depressed

1

Engine is running 

→

 OFF

—

—

1

Power supply position

Engine start/stop condition

Push-button ignition switch 

operation frequency

Selector lever position

Brake pedal operation condition

Engine is running 

→

 ACC 

—

—

Emergency stop operation

Engine stall return operation 
while driving 

N position

Not depressed

1

PCS

DIAGNOSIS SYSTEM (BCM)

PCS-39

< SYSTEM DESCRIPTION >

[POWER DISTRIBUTION SYSTEM]

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DIAGNOSIS SYSTEM (BCM)

COMMON ITEM

COMMON ITEM : CONSULT-III Function (BCM - COMMON ITEM)

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APPLICATION ITEM

CONSULT-III performs the following functions via CAN communication with BCM.

SYSTEM APPLICATION

BCM can perform the following functions for each system.
NOTE:
It can perform the diagnosis modes except the following for all sub system selection items.

×

: Applicable item

*: This item is indicated, but not used.

FREEZE FRAME DATA (FFD)

The BCM records the following vehicle condition at the time a particular DTC is detected, and displays on
CONSULT-III.

Diagnosis mode

Function Description

Work Support

Changes the setting for each system function.

Self Diagnostic Result

Displays the diagnosis results judged by BCM. Refer to 

BCS-57, "DTC Index"

.

CAN Diag Support Monitor

Monitors the reception status of CAN communication viewed from BCM. Refer to CONSULT-III opera-
tion manual.

Data Monitor

The BCM input/output signals are displayed.

Active Test

The signals used to activate each device are forcibly supplied from BCM.

Ecu Identification

The BCM part number is displayed.

Configuration

• Read and save the vehicle specification.
• Write the vehicle specification when replacing BCM.

System

Sub system selection item

Diagnosis mode

Work Support

Data Monitor

Active Test

Door lock

DOOR LOCK

×

×

×

Rear window defogger

REAR DEFOGGER

×

×

Warning chime

BUZZER

×

×

Interior room lamp timer

INT LAMP

×

×

×

Exterior lamp

HEAD LAMP

×

×

×

Wiper and washer

WIPER

×

×

×

Turn signal and hazard warning lamps

FLASHER

×

×

×

—

AIR CONDITONER*

×

×

• Intelligent Key system
• Engine start system

INTELLIGENT KEY

×

×

×

Combination switch

COMB SW

×

Body control system

BCM

×

IVIS

IMMU

×

×

×

Interior room lamp battery saver

BATTERY SAVER

×

×

×

Back door

TRUNK

×

Vehicle security system

THEFT ALM

×

×

×

RAP system

RETAINED PWR

×

Signal buffer system

SIGNAL BUFFER

×

×