2008 INFINITI QX56 ESP

FOREWORD
This manual contains maintenance and repair procedure for the 2008
INFINITI QX56.
In order to assure your safety and the efficient functioning of the vehicle,
this manual should be read thoroughly. It is especially important that the
PRECAUTIONS in the GI section be completely understood before starting
any repair task.
All information in this manual is based on the latest product information
at the time of publication. The right is reserved to make changes in specifi-
cations and methods at any time without notice.
IMPORTANT SAFETY NOTICE
The proper performance of service is essential for both the safety of
the technician and the efficient functioning of the vehicle.
The service methods in this Service Manual are described in such a
manner that the service may be performed safely and accurately.
Service varies with the procedures used, the skills of the technician
and the tools and parts available. Accordingly, anyone using service
procedures, tools or parts which are not specifically recommended
by NISSAN must first be completely satisfied that neither personal
safety nor the vehicle’s safety will be jeopardized by the service
method selected.

AV
DIAGNOSIS SYSTEM (AV CONTROL UNIT)AV-23
< FUNCTION DIAGNOSIS > [AUDIO SYSTEM]
C
D
E
F
G H
I
J
K L
M B A
O P
OPERATION PROCEDURE
1. Start the engine.
2. Turn the audio system off.
3. While pressing the “SETTING” button, turn the volume control dial counterclockwise 30 clicks or more.
CONFIRMATION/
ADJUSTMENT Display diagnosis
Color spectrum bar Color tone of the screen can be checked by the display of a color bar.
Gradation bar Shading of the screen can be checked by the display of a gray scale.
Touch panel
• Touch panel calibration
• Touch panel response check
Vehicle signals The following vehicle signals are analyzed: Vehicle speed signal, park-
ing brake signal, light signal, ignition switch signal, and reverse signal.
Speaker test Connection can be checked by sending a test tone to each speaker.
Navigation Steering angle ad-
justment
Confirm/adjust the steering angle when there is a difference between
the displayed vehicle mark turning angle and actual.
Speed calibration Confirm/adjust the speed calibration when there is a difference between
the displayed vehicle mark location and actual.
XM SAT subscrip-
tion status Check the subscription status of the XM NAV Traffic subsription.
Error history Diagnosis results previously stored in the memory are displayed in this
mode.
Synchronize FES clock Turns FES (Familly Entertainment System) clock synchronization func-
tion ON/OFF.
Vehicle CAN diagnosis The transmitting/receiving of CAN communication can be monitored.
AV COMM diagnosis The transmitting/receiving of AV communication can be monitored.
Handsfree phone Handsfree volume
adjustment
Adjust handsfree volume (low, medium, high).
Voice microphone
test Test microphone operation.
Delete handsfree
memory Erase handsfree system memory.
Bluetooth Confirm/Change
passkey
Confirm and change the Bluetooth passkey
Confirm/Change
device name Confirm and change a device name stored in Bluetooth.
SAT Change channel
Any necessary channels required to recieve traffic information from the
satellite radio system can be set.
Change applica-
tion ID Any application ID’s required to recieve traffic information from the sat-
ellite radio system can be set.
Diag Not used.
Delete unit connection log Erase the error history and connection history of the unit.
Initialize settings All audio settings are reset to default levels.
Mode
Description
ALNIA0446GB
Revision: March 2010 2008 QX56

AV
NORMAL OPERATING CONDITIONAV-153
< SYMPTOM DIAGNOSIS > [AUDIO SYSTEM]
C
D
E
F
G H
I
J
K L
M B A
O P
NORMAL OPERATING CONDITION
DescriptionINFOID:0000000001696149
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: March 2010
2008 QX56

BCS
COMBINATION SWITCH READING SYSTEMBCS-9
< FUNCTION DIAGNOSIS > [BCM]
C
D
E
F
G H
I
J
K L
B A
O P
N
- The voltage waveform of INPUT corresponding to the
formed circuit changes according to the operation of
the transistor on OUTPUT side if any (1 or more) switches are ON.
- It reads this change of the voltage as the status signal of the combination switch.
Operation Example
In the following operation example, the combination of t he status signals of the combination switch is replaced
as follows: INPUT 1 - 5 to “1 - 5” and OUTPUT 1 - 5 to “A - E”.
Example 1: When a switch (TURN RH switch) is turned ON
• The circuit between INPUT 1 and OUTPUT 5 is formed when the TURN RH switch is turned ON.
• BCM detects the combination switch status signal “1 E” when the signal of OUTPUT 5 is input to INPUT 1.
• BCM judges that the TURN RH switch is ON when the signal “1E” is detected.
Example 2: When some switches (turn RH s witch, front wiper LO switch) are turned ON
JPMIA0068GB
ALMIA0260GB
Revision: March 2010 2008 QX56

C1178, C1181, C1184, C1189 ABS ACTIVE BOOSTER
BRC-73
< COMPONENT DIAGNOSIS > [VDC/TCS/ABS]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
C1178, C1181, C1184, C1189 ABS ACTIVE BOOSTER
DescriptionINFOID:0000000001686340
The active brake booster consists of a vacuum boos ter, an active booster control group and a delta stroke
sensor. If a brake booster system malfunction occurs due to loss of vacuum, the delta stroke sensor will signal
the ABS actuator and electric unit (control unit) that a booster malfunction has occurred. The active booster
then applies supplemental force to the master cylinder re lative to the amount of force exerted on the brake
pedal.
DTC LogicINFOID:0000000001686341
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-73, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001686342
INSPECTION PROCEDURE
1.CONNECTOR INSPECTION
1. Turn the ignition switch OFF.
2. Disconnect the active booster connector E49 and ABS ac tuator and electric unit (control unit) connector
E125 and inspect the terminals for deforma tion, disconnection, looseness, or damage.
Is the inspection result normal?
YES >> GO TO 2
NO >> Repair connector.
2.ACTIVE BOOSTER CIRCUIT INSPECTION
DTC Display item Malfunction detected condition Possible cause
C1178 ABS ACTIVE BOOSTER SV
NG Active booster solenoid is malfunctioning, or signal line of
active booster servo is open or shorted.
• Harness or connector
• Active booster
• ABS actuator and electric unit (control unit)
C1181
ABS ACTIVE BOOSTER RE-
SPONSE NG Active booster response is malfunctioning, or signal line
of active booster response is open or shorted.
C1184 ABS BRAKE RELEASE SW
NG Brake release switch is malfunctioning, or signal line of
brake release switch is open or shorted.
C1189 ABS BRAKE BOOSTER DE-
FECT Brake booster is defective or malfunctioning.
Self-diagnosis results
ABS ACTIVE BOOSTER SV NG
ABS ACTIVE BOOSTER RESPONSE NG ABS BRAKE RELEASE SW NG
ABS BRAKE BOOSTER DEFECT
Revision: March 2010 2008 QX56

BRC-78
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1185 ICC UNIT
C1185 ICC UNIT
DescriptionINFOID:0000000001691164
When the force applied to brake pedal exceeds a certain level, the brake assist is activated and generates a
greater braking force than that of a convent
ional brake booster, even with light pedal force.
When the ICC preview function identifies the need to apply the sudden brake by sensing the vehicle ahead in
the same lane and the distance and relative speed from it, it applies the brake pre-pressure before driver
depresses the brake pedal and improves brake response by reducing its free play.
DTC LogicINFOID:0000000001691165
DTC DETECTION LOGIC
DTC CONFIRMATION PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Check the self-diagnosis results.
Is above displayed on the self-diagnosis display?
YES >> Proceed to diagnosis procedure. Refer to BRC-78, "Diagnosis Procedure".
NO >> Inspection End
Diagnosis ProcedureINFOID:0000000001691166
INSPECTION PROCEDURE
1.SELF-DIAGNOSIS RESULT CHECK
Perform self-diagnosis of ICC unit.
Are self-diagnosis result items displayed?
YES >> After checking and repairing the applicable item, perform ICC unit self-diagnosis again.
NO >> GO TO 2
2.CONNECTOR INSPECTION
Disconnect the ABS actuator and electric unit (contro l unit) connector and the ICC unit connector and check
the terminals for deformation, disconnection, looseness or damage.
Is the inspection result normal?
YES >> GO TO 3
NO >> Repair or replace as necessary.
3.ICC UNIT CIRCUIT INSPECTION
DTC Display item Malfunction detected condition Possible cause
C1185 ABS ACC CU INTERNAL NG ICC cont rol unit internal malfunction.• Harness or connector
• ICC unit
• ABS actuator and electric unit
(control unit)
Self-diagnosis results
ABS ACC CU INTERNAL NG
Revision: March 2010 2008 QX56

ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)BRC-101
< ECU DIAGNOSIS > [VDC/TCS/ABS]
C
D
E
G H
I
J
K L
M A
B
BRC
N
O P
C1145 YAW RATE SENSOR
BRC-40, "Description"C1146SIDE G-SEN CIRCUIT
C1155 BR FLUID LEVEL LOW BRC-64, "
Description"
C1156ST ANG SEN COM CIR BRC-67, "Description"
C1160DECEL G SEN SET BRC-68, "Description"
C1163ST ANGL SEN SAFE BRC-69, "Description"
C1164CV1
BRC-70, "
Description"C1165CV2
C1166 SV1
C1167 SV2
C1170 VARIANT CORDING BRC-37, "
DTC Logic"
C1178ABS ACTIVE BOOSTER SV NG BRC-73, "Description"
C1179ABS DELTA S SEN NG BRC-76, "Description"
C1181ABS ACTIVE BOOSTER RESPONSE NG
BRC-73, "Description"C1184ABS BRAKE RELEASE SW NG
C1185 ABS ACC CU INTERNAL NG BRC-78, "
Description"
C1189ABS BRAKE BOOSTER DEFECT BRC-73, "Description"
U1000CAN COMM CIRCUIT BRC-80, "Description"
DTCItems (CONSULT screen terms) Reference
Revision: March 2010 2008 QX56

BRC-108
< SYMPTOM DIAGNOSIS >[VDC/TCS/ABS]
VEHICLE JERKS DURING VDC/TCS/ABS CONTROL
VEHICLE JERKS DURING
VDC/TCS/ABS CONTROL
Diagnosis ProcedureINFOID:0000000001686380
1.SYMPTOM CHECK
Check if the vehicle jerks during VDC/TCS/ABS control.
Is the inspection result normal?
YES >> Normal.
NO >> GO TO 2
2.CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis of ABS actuator and electric unit (control unit). Refer to \
BRC-24, "
CONSULT-III Func-
tion (ABS)".
Are self-diagnosis results indicated?
YES >> Check corresponding items, make repairs, and perform ABS actuator and electric unit (control
unit) self-diagnosis.
NO >> GO TO 3
3.CHECK CONNECTOR
• Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector and check
terminal for deformation, disconnection, looseness, etc.
• Securely connect connectors and perform ABS actuator and electric uni t (control unit) self-diagnosis.
Are self-diagnosis results indicated?
YES >> If poor contact, damage, open or short circuit of connector terminal is found, repair or replace.
NO >> GO TO 4
4.CHECK ECM AND TCM SELF-DIAGNOSIS RESULTS
Perform ECM and TCM self-diagnosis.
Are self-diagnosis results indicated?
YES >> Check the corresponding items. • ECM: Refer to EC-63, "
CONSULT-III Function (ENGINE)".
• TCM: Refer to TM-32, "
CONSULT-III Function (TRANSMISSION)".
NO >> Replace ABS actuator and electric unit (control unit). Refer to BRC-116, "
Removal and Installa-
tion".
Revision: March 2010 2008 QX56