2008 INFINITI QX56 power steering

BRC-36
< COMPONENT DIAGNOSIS >[VDC/TCS/ABS]
C1109 POWER AND GROUND SYSTEM
5. Check continuity between ABS actuator and electric unit (control
unit) harness connector terminals and ground.
Is the inspection result normal?
YES >> Check battery for terminal looseness, low voltage, etc. If any malfunction is found, repair malfunc-
tioning parts.
NO >> Repair or replace malfunctioning components.
Special Repair RequirementINFOID:0000000001691102
1.ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL POSITION
Always perform neutral position adjustment for the st eering angle sensor when replacing the ABS actuator
and electric unit (control unit). Refer to BRC-8, "
ADJUSTMENT OF STEERING ANGLE SENSOR NEUTRAL
POSITION : Description".
>> GO TO 2
2.CALIBRATION OF DECEL G SENSOR
Always perform calibration of decel G sensor when replac ing the ABS actuator and electric unit (control unit).
Refer to BRC-9, "
CALIBRATION OF DECEL G SENSOR : Description".
>> END
ABS actuator and electric unit (control unit) —Contin u it y
Connector Terminal
E125 16, 47 Ground Yes
AWFIA0016ZZ
Revision: March 2010 2008 QX56

BRC-110
< PRECAUTION >[VDC/TCS/ABS]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint Syst
em (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004873045
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004873055
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56

CCS
INTELLIGENT CRUISE CONTROL SYSTEMCCS-13
< FUNCTION DIAGNOSIS >
C
DE
F
G H
I
J
K L
M B
N P A
INTELLIGENT CRUISE CONTROL SYSTEM
System DiagramINFOID:0000000001731809
System DescriptionINFOID:0000000001731810
• The Intelligent Cruise Control (ICC) system automatic ally maintains a selected distance from the vehicle
ahead according to that vehicle's speed, or at the set speed, if the road ahead is clear.
• The ICC function has two cruise control modes and brake assist (with preview function).
• To activate or deactivate the ICC system and set the vehicle speed and vehicle-to-vehicle distance, use the
ICC steering switch.
• The operation status of the ICC system is indicated on the ICC system display of the combination meter.
VEHICLE-TO-VEHICLE DISTANCE CONTROL MODE
• Vehicle-to-vehicle distance control mode, the vehicle can maintain the same speed as other vehicles without
the constant need to adjust the set speed as the dr iver would with a normal cruise control system.
• The system is intended to enhance the operation of the v ehicle when following the vehicle traveling in the
same lane and direction.
• If the ICC sensor integrated unit detects a slow er moving vehicle ahead, the system will reduce speed so
that the vehicle ahead can be followed at the selected distance.
• The system automatically controls the throttle and applies the brakes (up to 25% of vehicle braking power) if necessary.
• The detection range of the sensor is approximately 390 ft (120 m) ahead.
• Refer to Owner's Manual for Intelligent Cr uise Control System operating instructions.
CONVENTIONAL (FIXED SPEED) CRUISE CONTROL MODE
• Conventional (fixed speed) cruise control mode is cruising at preset speeds.
• Refer to Owner's Manual for Intelligent Cruise Control System operating instructions.
BRAKE ASSIST (WITH PREVIEW FUNCTION)
• 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 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.
• Refer to Owner's Manual for BRAKE ASSIST (WITH PREVIEW FUNCTION) operating instructions.
WKIA1976E
Revision: March 2010 2008 QX56

CCS
DIAGNOSIS SYSTEM (ICC SENSOR INTEGRATED UNIT)
CCS-17
< FUNCTION DIAGNOSIS >
C
D E
F
G H
I
J
K L
M B
N P A
DIAGNOSIS SYSTEM (ICC SENSOR INTEGRATED UNIT)
Diagnosis DescriptionINFOID:0000000001731813
The ICC system includes the on board self-diagnosis functi on that allows the technician to check for any trou-
ble codes on the ICC system display by operating the ICC steering switch.
ON BOARD SELF-DIAGNOSIS OPERETION PROCEDURE
1. Turn ignition switch OFF.
2. Start engine.
3. From 5 seconds through 15 seconds after start engine, press
RESUME/ACCELERATE switch 5 times, and SET/COAST
switch 5 times.
NOTE:
• Never turn the MAIN switch ON.
• When operation above is not completed from 5 secondsthrough 15 seconds, start again from above go to 1.
4. When the on board self-diagnosis starts up, the ICC system display shows DTC No. (1) at the set vehicle speed indicator. Refer to CCS-55, "
Diagnostic Trouble Code (DTC) Chart".
NOTE:
• DTC will disappear after 5 minutes.
• When more than one malfunction is detected, a maxi mum of 3 code numbers can be stored; the latest
malfunction will be displayed first.
WHEN ON BOARD SELF-DIAGNOSIS WILL NOT START UP
If the on board self-diagnosis does not start up, check the following items.
PKIB8371E
JSOIA0008GB
Assumed abnormal point Inspection item
ICC steering switch malfunction. Perform the inspection for DTC 46 OPERATION SW CIRC. Refer to CCS-30, "
DTC
46 OPERATION SW CIRC" .
Harness malfunction between ICC
steering switch and ECM.
ECM malfunction.
ICC unit malfunction. • Inspect the ICC sensor power and ground circuits. Refer to
CCS-25, "
DTC 31
POWER SUPPLY CIR1, DTC 34 POWER SUPPLY CIR2"
• Perform the self-diagnosis for the ICC unit with CONSULT-III, and check the diag-
nosis results. Refer to CCS-55, "
Diagnostic Trouble Code (DTC) Chart".
Revision: March 2010 2008 QX56

CCS
DIAGNOSIS SYSTEM (ICC SENSOR INTEGRATED UNIT)
CCS-19
< FUNCTION DIAGNOSIS >
C
D E
F
G H
I
J
K L
M B
N P A
• Last five cancel (system cancel) causes are displayed.
• “CAUSE OF AUTO-CANCEL” displays times of ignition switch ON/OFF up to 254 maximum. 254 is kept though the number exceeds 254. The num ber returns to 0 when detecting the same cancellation causes.
SELF DIAGNOSTIC RESULT
For details, refer to CCS-55, "Diagnostic Trouble Code (DTC) Chart".
NOTE:
“DTC RESULTS” and “TIME” are indicated on “Self Diagnostic Result”. “TIME” is used as a reference data of
diagnosis. It shows when malfunction is detected.
“TIME” shows the following.
• 0: malfunction is detected at present (from malfunction detection to ignition switch OFF).
CAN communication ([U1000], [U1010])
• 1 ~ 39: Displays when it is normal at present and finds malfunction in the past. It increases like
0→ 1→ 2...38→ 39 after returning to the normal condition whenever IGN OFF→ ON. If it is over 39, it is fixed to
39 until the self-diagnostic results are erased. It retu rns to 0 when malfunction is detected again in the pro-
cess.
Other than CAN communication (other than [U1000], [U1010])
• 1 ~ 49: Displays when it is normal at present and finds malfunction in the past. It increases like 0→ 1→ 2...48→ 49 after returning to the normal condition whenever IGN OFF→ ON. If it is over 49, it is fixed to
49 until the self-diagnostic results are erased. It retu rns to 0 when malfunction is detected again in the pro-
cess.
DATA MONITOR
× : Applicable
VDC/TCS OFF SW ×VDC OFF switch was pressed.
WHEEL SPD UNMATCH ××Wheel speed became different from A/T vehicle speed.
TIRE SLIP ××Wheel slipped.
IGN LOW VOLT ××Power supply voltage became low.
NO RECORD ××—
Monitored Item [unit]MAIN
SIGNALS SELECTION
FROM
MENU Description
VHCL SPEED SE
[km/h] or [mph] ××Indicates vehicle speed calculated from ICC sensor integrated unit through
CAN communication [ABS actuator and electric unit (control unit) transmits
vehicle speed signal (wheel speed) through CAN communication].
SET VHCL SPD
[km/h] or [mph] ××
Indicates set vehicle speed memorized in ICC sensor integrated unit.
THRTL OPENING
[%] ××Indicates throttle position read from ICC sensor integrated unit through CAN
communication (ECM transmits accelerator pedal position signal through
CAN communication).
THRTL SENSOR
[deg] ××NOTE:
This item is displayed, but cannot monitor.
SET DISTANCE
[SHOR/MID/LONG] ××
Indicates set distance memorized in ICC sensor integrated unit.
MAIN SW
[On/Off] ××
Indicates [On/Off] status as judged from ICC steering switch signal (ECM
transmits ICC steering switch signal through CAN communication).
SET/COAST SW
[On/Off] ××Indicates [On/Off] status as judged from ICC steering switch signal (ECM
transmits ICC steering switch signal through CAN communication).
CANCEL SW
[On/Off] ××Indicates [On/Off] status as judged from ICC steering switch signal (ECM
transmits ICC steering switch signal through CAN communication).
RESUME/ACC SW
[On/Off] ××
Indicates [On/Off] status as judged from ICC steering switch signal (ECM
transmits ICC steering switch signal through CAN communication).
DISTANCE SW
[On/Off] ×Indicates [On/Off] status as judged from ICC steering switch signal (ECM
transmits ICC steering switch signal through CAN communication).
CRUISE OPE
[On/Off] ××
Indicates whether controlling or not (ON means “controlling”).
Revision: March 2010 2008 QX56

CCS
ICC UNITCCS-55
< ECU DIAGNOSIS >
C
DE
F
G H
I
J
K L
M B
N P A
Diagnostic Trouble Code (DTC) ChartINFOID:0000000001757410
× :Applicable
DTC
No. CONSULT-III screen terms ICC sys-
tem
warning lamp Fail-safe
Malfunctions detected where... Refer-
ence
page
Veh ic le-
to-vehi-cle dis-
tance
control mode Conven-
tional
(fixed
speed) cruise
control mode Brake as-
sist (with
preview
function)
11 CONTROL UNIT ×××× • ICC unit internal malfunctionCCS-22
12 VDC CONTROL UNIT ×××× • VDC malfunction
• Brake booster signal harness is
open or shorted CCS-23
20 CAN COMM CIRCUIT
×××× • ICC unit detected CAN communi-
cation malfunction CCS-24
31 POWER SUPPLY CIR1
×××× • ICC unit power supply voltage is
excessively low (less than 8V) CCS-25
34 POWER SUPPLY CIR2
×××× • ICC unit power supply voltage is
excessively high. CCS-25
41 VHCL SPEED SE CIRC
×××× • Wheel sensor malfunction
• ABS actuator and electric unit
(control unit) malfunction
• A/T vehicle speed sensor mal-
function
•TCM malfunction CCS-26
43 VDC/TCS/ABS CIRC
×××× • VDC/TCS/ABS system malfunc-
tion CCS-27
45 BRAKE SW/ STOP L SW
×××× • ICC brake switch or stop lamp
switch harness is open or shorted
• ICC brake switch or stop lamp switch is stuck to OFF
• ICC brake switch or stop lamp switch is stuck to ON CCS-28
46 OPERATION SW CIRC
××× • ICC steering switch harness or
spiral cable is open or shorted
• ICC steering switch malfunction CCS-30
74 LASER BEAM OFF CNTR
××ו Laser beam of ICC sensor is off
the aiming point CCS-31
90 STOP LAMP RLY FIX
××ו Normally open terminal of stop
lamp relay is stuck CCS-32
92 ECM CIRCUIT
×××× •ECM malfunction
• Accelerator pedal position sensor
malfunction
• ICC unit malfunction CCS-37
96 NP RANGE
××× • Transmission range switch har-
ness is open or shorted
• Transmission range switch mal- function
•TCM malfunction CCS-38
97 AT CIRCUIT
××× •TCM malfunctionCCS-39
98 GEAR POSITION ××× •TCM malfunction
• A/T input speed sensor malfunc-
tion
• A/T vehicle speed sensor mal- function CCS-40
Revision: March 2010
2008 QX56

CHG
CHG-1
ELECTRICAL & POWER CONTROL
C
DE
F
G H
I
J
K L
B
SECTION CHG
A
O P
N
CONTENTS
CHARGING SYSTEM
PRECAUTION .......
........................................2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Precaution for Power Generation Variable Voltage
Control System ..........................................................
3
PREPARATION ............................................4
PREPARATION .............................................. .....4
Special Service Tool ........................................... ......4
Commercial Service Tool ..........................................4
BASIC INSPECTION ....................................5
DIAGNOSIS AND REPAIR WORKFLOW ..... .....5
Work Flow ........................................................... ......5
FUNCTION DIAGNOSIS ...............................8
CHARGING SYSTEM ..................................... .....8
System Diagram .................................................. ......8
System Description ...................................................8
Component Description ............................................8
POWER GENERATION VOLTAGE VARI-
ABLE CONTROL SYSTEM .................................
9
System Diagram .................................................. ......9
System Description ...................................................9
Component Description .............................................9
COMPONENT DIAGNOSIS .........................10
CHARGING SYSTEM PRELIMINARY IN-
SPECTION ....... .................................................
10
Inspection Procedure ........................................... ....10
POWER GENERATION VOLTAGE VARI-
ABLE CONTROL SYSTEM OPERATION IN-
SPECTION ........................................................
11
Inspection Procedure ........................................... ....11
B TERMINAL CIRCUIT .....................................13
Description ...............................................................13
Diagnosis Procedure ...............................................13
L TERMINAL CIRCUIT .....................................14
Description ...............................................................14
Diagnosis Procedure ...............................................14
S TERMINAL CIRCUIT .....................................15
Description ...............................................................15
Diagnosis Procedure ...............................................15
CHARGING SYSTEM .......................................16
Wiring Diagram ........................................................16
SYMPTOM DIAGNOSIS ..............................21
CHARGING SYSTEM .......................................21
Symptom Table ................................................... ....21
ON-VEHICLE REPAIR .................................22
GENERATOR ....................................................22
Removal and Installation ..................................... ....22
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... ...
23
GENERATOR ....................................................23
Generator ............................................................ ....23
Revision: March 2010 2008 QX56

CHG-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004857596
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004857595
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56