2009 INFINITI QX56 ECU

AV-154
< ECU DIAGNOSIS >[AUDIO SYSTEM]
DVD PLAYER
17
(R) 18
(G) DVD audio signal RH Output Ignition
switch ON With DVD player operation
21
(Y) Ground Battery power
Input ——Battery voltage
22
(R/L) Ground Illumination power
Input —With instrument illumination
ON Battery voltage
23
(P/B) Ground CAN communication
Input/
Output Ignition
switch
ON —0
V
24
(V) Ground ACC power
InputIgnition
switch
ACC or
ON —
Battery voltage
25
(BR) Ground Video monitor power Output Ignition
switch ON With DVD player operation
Battery voltage
26
(B/Y) Ground Video monitor ground Input Ignition
switch ON With instrument illumination
ON 0V
28
(B/W) Ground Video out
InputIgnition
switch
ACC or
ON —
30 — Shield — — ——
32
(BR) — Data transmit
Output ———
Terminal
(Wire color) Description
ConditionReference value
(Approx.)
+ – Signal nameInput/
Output
SKIB3609E
SKIB2251J
Revision: December 20092009 QX56

AV
NORMAL OPERATING CONDITIONAV-157
< SYMPTOM DIAGNOSIS > [AUDIO SYSTEM]
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NORMAL OPERATING CONDITION
DescriptionINFOID:0000000003776899
AUDIO SYSTEM
The majority of the audio troubles are the result of outside causes (bad CD, electromagnetic interference,
etc.).
Noise
The following noise results from variations in field strength, such as fading noise and multi-path noise, or
external noise from trains and other sources. It is not a malfunction.
• Fading noise: This noise occurs because of variations in the field strength in a narrow range due to moun-
tains or buildings blocking the signal.
• Multi-path noise: This noise results from the waves sent directly from the broadcast station arriving at the antenna at a different time from the waves which reflect off mountains or buildings.
The vehicle itself can be a source of noise if noise prevention parts or electrical equipment is malfunctioning.
Check if noise is caused and/or changed by engine speed, ignition switch turned to each position, and opera-
tion of each piece of electrical equipment, and determine the cause.
NOTE:
The source of the noise can be found easily by listening to the noise while removing the fuses of electrical
components, one by one.
Type of Noise and Possible Cause
NAVIGATION SYSTEM
Basic Operation
Vehicle Mark
Occurrence condition Possible cause
Occurs only when engine is ON. A continuous growling noise occurs. The speed of
the noise varies with changes in the engine speed. • Ignition components
The occurrence of the noise is linked with the operation of the fuel pump. • Fuel pump condenser
Noise only occurs when various
electrical components are oper-
ating. A cracking or snapping sound occurs with the op-
eration of various switches.
• Relay malfunction, audio unit malfunction
The noise occurs when various motors are operat-
ing. • Motor case ground
•Motor
The noise occurs constantly, not just under certain conditions. • Rear defogger coil malfunction
• Open circuit in printed heater
• Poor ground of antenna feeder line
A cracking or snapping sound occurs while the vehicle is being driven, especially when
it is vibrating excessively. • Ground wire of body parts
• Ground due to improper part installation
• Wiring connections or a short circuit
Symptom
Cause Remedy
No image is shown. Display brightness adjustment is set fully to DARK
side. Adjust the display brightness.
No guide sound is heard.
Audio guide volume is too low or
too high. Volume control is set to OFF, MIN or MAX. Adjust the audio guide volume.
Audio guidance is not available while the vehicle is
driving on a dark pink route.
System is not malfunctioning.
Screen is too dark.
Motion of the image is too slow. Temperature inside the vehicle is low.
Wait until the temperature inside the vehicle
reaches the proper temperature.
Small black or bright spots appear
on the screen. Symptom peculiar to a liquid crystal display (dis-
play unit). System is not malfunction.
Revision: December 20092009 QX56

BCS-2
COMB SW .................................................................24
COMB SW : CONSULT-III Function (BCM -
COMB SW) .............................................................
24
IMMU ...................................................................... ...25
IMMU : CONSULT-III Function (BCM - IMMU) .......25
BATTERY SAVER ................................................. ...25
BATTERY SAVER : CONSULT-III Function (BCM
- BATTERY SAVER) ........................................... ...
25
TRUNK ................................................................... ...26
TRUNK : CONSULT-III Function (BCM - TRUNK) ...26
RETAINED PWR .................................................... ...26
RETAINED PWR : CONSULT-III Function (BCM -
RETAINED PWR) ...................................................
26
SIGNAL BUFFER ................................................... ...26
SIGNAL BUFFER : CONSULT-III Function (BCM
- SIGNAL BUFFER) ................................................
26
AIR PRESSURE MONITOR ................................... ...27
AIR PRESSURE MONITOR : Diagnosis Descrip-
tion ..........................................................................
27
AIR PRESSURE MONITOR : CONSULT-III Func-
tion ..........................................................................
28
THEFT ALM ........................................................... ...29
THEFT ALM : CONSULT-III Function (BCM -
THEFT ALM) ..........................................................
29
COMPONENT DIAGNOSIS ........................30
U1000 CAN COMM CIRCUIT ......................... ...30
Description ........................................................... ...30
DTC Logic ...............................................................30
Diagnosis Procedure ..............................................30
U1010 CONTROL UNIT (CAN) .........................31
DTC Logic ............................................................ ...31
Diagnosis Procedure ..............................................31
Special Repair Requirement ...................................31
POWER SUPPLY AND GROUND CIRCUIT .....32
Diagnosis Procedure ............................................ ...32
COMBINATION SWITCH INPUT CIRCUIT .......33
Diagnosis Procedure ............................................ ...33
Special Repair Requirement ...................................34
COMBINATION SWITCH OUTPUT CIRCUIT ...35
Diagnosis Procedure ...............................................35
Special Repair Requirement ...................................35
COMBINATION SWITCH ..................................36
Description ........................................................... ...36
Diagnosis Procedure ...............................................36
ECU DIAGNOSIS .......................................38
BCM (BODY CONTROL MODULE) ............... ...38
Reference Value .................................................. ...38
Terminal Layout ......................................................40
Physical Values .......................................................40
Wiring Diagram .......................................................46
Fail Safe .................................................................50
DTC Inspection Priority Chart ...............................51
DTC Index ..............................................................51
SYMPTOM DIAGNOSIS ............................53
COMBINATION SWITCH SYSTEM SYMP-
TOMS .............................................................. ...
53
Symptom Table .................................................... ...53
PRECAUTION ............................................54
PRECAUTIONS .............................................. ...54
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
54
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ..................................
54
ON-VEHICLE REPAIR ...............................56
BCM (BODY CONTROL MODULE) ............... ...56
Removal and Installation ...................................... ...56
Revision: December 20092009 QX56

BCS
BODY CONTROL SYSTEMBCS-5
< FUNCTION DIAGNOSIS > [BCM]
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FUNCTION DIAGNOSIS
BODY CONTROL SYSTEM
System DescriptionINFOID:0000000003776377
OUTLINE
 BCM (Body Control Module) controls
the various electrical components. It inputs the information required to
the control from CAN communication and the si gnal received from each switch and sensor.
 BCM has combination switch reading function for reading the operation status of combination switches (light,
turn signal, wiper and washer) in addition to a function fo r controlling the operation of various electrical com-
ponents. It also has the signal transmission function as the passed point of signal and the power consump-
tion control function that reduces the power consumption with the ignition switch OFF.
 BCM is equipped with the diagnosis function that perfo rms the diagnosis with CONSULT-III and various set-
tings.
BCM control function list
System Refer to
Combination switch reading system BCS-7, "System Diagram"
Signal buffer systemBCS-12, "System Diagram"
Power consumption control systemBCS-13, "System Diagram"
Auto light systemEXL-11, "System Diagram"
Turn signal and hazard warning lamp systemEXL-15, "System Diagram"
Headlamp systemEXL-7, "System Diagram"
Front fog lamp systemEXL-14, "System Diagram"
Daytime running light systemEXL-9, "System Diagram"
Interior room lamp control systemINL-6, "System Diagram"
Step lamp systemINL-6, "System Diagram"
Interior room lamp battery saver systemINL-6, "System Diagram"
Front wiper and washer systemWW-4, "System Diagram"
Rear wiper and washer systemWW-8, "System Diagram"
Warning chime systemWCS-4, "WARNING CHIME SYSTEM : System Diagram"
Door lock systemDLK-14, "DOOR LOCK AND UNLOCK SWITCH : System Diagram"
(NATS) Nissan anti-theft system SEC-11, "System Diagram"
Vehicle security systemSEC-15, "System Diagram"
Rear window defogger systemDEF-4, "System Diagram"
Intelligent Key systemSEC-7, "System Diagram"
Power window systemPWC-5, "System Diagram"
RAP (retained accessory power) systemBCS-26, "RETAINED PWR : CONSULT-
III Function (BCM - RETAINED PWR)"
TPMS (tire pressure monitoring system) BCS-28, "AIR PRESSURE MONITOR : CONSULT-III Function"
Revision: December 20092009 QX56

BCS-14
< FUNCTION DIAGNOSIS >[BCM]
POWER CONSUMPTION CONTROL SYSTEM
Sleep condition
Wake-up operation
 BCM transmits sleep wake up signal (wake up) to eac
h unit when any condition listed below is established,
and then goes into normal mode from low power consumption mode.
 Each unit starts transmissions with CAN communication by receiving sleep wake up signals. Each unit trans-
mits wake up signals to BCM with CAN communication to convey the start of CAN communication.
Wake-up condition
CAN sleep condition B CM sleep condition
 Receiving the sleep-ready signal (ready) from all units
 Ignition switch: OFF
 Vehicle security system alarm: No operation
 Warning lamp: No operation
 Warning chime: No operation
 Stop lamp switch: OFF
 Key switch status: No change for 2 seconds
 Hazard warning lamp: No operation
Exterior lamp: OFF
 Door lock status: No change for 2 seconds
 CONSULT-III communication status: No communication
 Door switch status: No change for 2 seconds The controls only BCM are completed.
(Interior room lamp battery saver: Time out etc.)
BCM wake-up condition
 Ignition switch: OFF → ACC or ON
 Stop lamp switch: ON (Depress brake pedal)
 Any door switch: OFF → ON
 Lighting switch: OFF → 1ST or PASS
 Hazard switch: OFF → ON
 Back door opener switch OFF → ON
 Remote keyless entry receiver: Receiving
 Intelligent Key unit: Receiving
Revision: December 20092009 QX56

BCS-16
< FUNCTION DIAGNOSIS >[BCM]
DIAGNOSIS SYSTEM (BCM)
DIAGNOSIS SYSTEM (BCM)
COMMON ITEM
COMMON ITEM : CONSULT-III Fu
nction (BCM - COMMON ITEM)INFOID:0000000003776387
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.
BCM
BCM : CONSULT-III Function (BCM - BCM)INFOID:0000000003776388
WORK SUPPORT
Diagnosis mode Function Description
WORK SUPPORT Changes the setting for each system function.
SELF-DIAG RESULTS Displays the diagnosis results judged by BCM. Refer to BCS-51, "DTC Index"
.
CAN DIAG SUPPORT MNTR Monitors the reception status of CAN communication viewed from BCM.
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  Enables to read and save the vehicle specification.
 Enables to write the vehicle specification when replacing BCM.
System Sub system selection item Diagnosis mode
WORK SUPPORT DATA MONITOR ACTIVE TEST
BCM BCM ×
Door lock DOOR LOCK ×××
Rear window defo gger REAR DEFOGGER ×
Warning chime BUZZER ××
Interior room lamp timer INT LAMP ×××
Remote keyless entry system MULTI REMOTE ENT ××
Exterior lamp HEAD LAMP ×××
Wiper and washer WIPER ×××
Turn signal and hazard warning lamps FLASHER ××
Air conditioner AIR CONDITONER ×
Intelligent Key system INTELLIGENT KEY ×
Combination switch COMB SW ×
Immobilizer IMMU ××
Interior room lamp battery saver BATTERY SAVER ×××
Back door open TRUNK ××
RAP (retained accessory power) RETAINED PWR ×××
Signal buffer system SIGNAL BUFFER ××
TPMS (tire pressure monitoring sys-
tem) AIR PRESSURE MONITOR
×××
Vehicle security system PANIC ALARM ×
Revision: December 20092009 QX56

BCS
DIAGNOSIS SYSTEM (BCM)BCS-25
< FUNCTION DIAGNOSIS > [BCM]
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IMMU
IMMU : CONSULT-III Function (BCM - IMMU)INFOID:0000000003776399
DATA MONITOR
ACTIVE TEST
BATTERY SAVER
BATTERY SAVER : CONSULT-III Function (BCM - BATTERY SAVER)INFOID:0000000003776400
WORK SUPPORT
*: Initial setting
DATA MONITOR
FR WIPER LOW
[OFF/ON]
Displays the status of the FR WIPER LOW switch in combination switch judged by BCM with the combination
switch reading function
FR WIPER INT
[OFF/ON] Displays the status of the FR WIPER INT switch in combination switch judged by BCM with the combination
switch reading function
FR WASHER SW
[OFF/ON] Displays the status of the FR WASHER switch in combination switch judged by BCM with the combination
switch reading function
INT VOLUME
[1 - 7] Displays the status of wiper intermittent dial position judged by BCM with the combination switch reading
function
RR WIPER ON
[OFF/ON] Displays the status of the RR WIPER switch in combination switch judged by BCM with the combination
switch reading function
RR WIPER INT
[OFF/ON] Displays the status of the RR WIPER INT switch in combination switch judged by BCM with the combination
switch reading function
RR WASHER SW
[OFF/ON] Displays the status of the RR WASHER switch in combination switch judged by BCM with the combination
switch reading function
Monitor Item
[Unit] Description
Monitor Item
[Unit] Description
IGN ON SW [ON/OFF] Indicates condition of ignition switch in ON position.
Test Item Description
THEFT IND This test is able to check security indicator operation [ON/OFF].
Work Item Setting Item Setting
ROOM LAMP TIMER SET MODE 1* 15 min.
Sets the interior room lamp battery saver timer operating
time.
MODE 2 30 min.
Monitor Item
[Unit] Description
IGN ON SW [ON/OFF] Ignition switch (ON) status judges from IGN signal (ignition power supply)
KEY ON SW [ON/OFF] The switch status input from key switch
DOOR SW-DR [ON/OFF] The switch status input from front door switch (driver side)
DOOR SW-AS [ON/OFF] The switch status input from front door switch (passenger side)
DOOR SW-RR [ON/OFF] The switch status input from rear door switch RH
DOOR SW- RL [ON/OFF] The switch status input from rear door switch LH
BACK DOOR SW [ON/OFF] The switch status input from back door switch
KEY CYL LK-SW [ON/OFF] Lock switch status input from door key cylinder switch
Revision: December 20092009 QX56

BCS
DIAGNOSIS SYSTEM (BCM)BCS-29
< FUNCTION DIAGNOSIS > [BCM]
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ID Read
The registered ID number is displayed.
ID Regist
Refer to
WT-6, "ID Registration Procedure".
SELF-DIAG RESULTS MODE
Operation Procedure
Refer to WT-12, "Self-Diagnosis (With CONSULT-III)".
DATA MONITOR MODE
Screen of data monitor mode is displayed. Refer to WT-11, "CONSULT-III Function (BCM)".
NOTE:
When malfunction is detected, CONSUL T-III perform REAL-TIME DIAGNOSIS.
Also, any malfunction detected while in this mode will be displayed at real time.
ACTIVE TEST MODE
NOTE:
Before performing the self-diagnosis, be sure to register the ID, or else the actual malfunction may be different
from that displayed on CONSULT-III.
TEST ITEM LIST
THEFT ALM
THEFT ALM : CONSULT-III Function (BCM - THEFT ALM)INFOID:0000000003776406
WORK SUPPORT
Test item Content
WARNING LAMP This test is able to check to make sure that the warning lamp turns on.
ID REGIST WARNING This test is able to check to make sure that the buzzer sounds or the warning lamp turns on.
FLASHER This test is able to check to make sure that each turn signal lamp turns on.
HORN This test is able to check to make sure that the horn sounds.
Work Item Description
SECURITY ALARM SET Vehicle security function mode can be changed in this mode.
 ON: Vehicle security function is ON.
 OFF: Vehicle security function is OFF.
Revision: December 20092009 QX56