2011 INFINITI QX56 wheel torque

COMPONENT PARTSBRC-143
< SYSTEM DESCRIPTION > [BRAKE ASSIST (WITH PREVIEW FUNCTION)]
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Component DescriptionINFOID:0000000006248457
× : Applicable
13. Steering angle sensor
Refer to BRC-10, "
Component Parts
Location"
14. ADAS control unit
Refer to DAS-13, "
Component Parts
Location"
A. Back side of engine room (RH) B. Front bumper (center) C. Upper side of brake pedal
D. Under side of instrument lower driver
panel
Component Function
Description
Vehicle-to-vehicle distance control mode
Conventional (fixed speed) cruise control mode Intelligent Brake Assist (IBA)
Brake Assist (with preview function)
ADAS control unit ×××× ADAS control unit calculates a target distance between vehicles
and a target speed, based on signals received from each sensor
and switch to transmit an engine torque command value to ECM
and a brake fluid pressure cont rol signal to ABS actuator and
electric unit (control unit) via CAN communication
 ADAS control unit transmits buzzer output signal to combination
meter via CAN communication
ICC sensor ×××× ICC sensor detects light reflected from a vehicle ahead by irra-
diating laser forward and calculates a distance from the vehicle
ahead and a relative speed, based on the detected signal
 ICC sensor transmits the presence/absence of vehicle ahead and the distance from the vehicle to ADAS control unit via ITS
communication
ECM ×××× ECM transmits the accelerator pedal position signal, ICC brake
switch signal, stop lamp switch signal, ICC steering switch sig-
nal, etc. to ADAS control unit via CAN communication
 ECM controls the electric throttle control actuator based on the engine torque demand received from the ADAS control unit via
CAN communication
ABS actuator and electric unit
(control unit) ×××× ABS actuator and electric unit (c
ontrol unit) transmits the vehicle
speed signal (wheel speed), stop lamp signal and VDC/TCS/
ABS system operation condition to ADAS control unit via CAN
communication
 ABS actuator and electric unit (c ontrol unit) controls the brake,
based on a brake fluid pressure control signal received from the
ADAS control unit via CAN communication
BCM ×BCM transmits the front wiper request signal to ADAS control unit
via CAN communication
TCM ××TCM transmits the signal related to A/T control to ADAS control
unit via CAN communication
Revision: 2010 May2011 QX56

BRC-150
< SYSTEM DESCRIPTION >[INTELLIGENT BRAKE ASSIST]
COMPONENT PARTS
Component Description
INFOID:0000000006248459
× : Applicable
13. Steering angle sensor
Refer to BRC-10, "
Component Parts
Location"
14. ADAS control unit
Refer to DAS-13, "
Component Parts
Location"
A. Back side of engine room (RH) B. Front bumper (center) C. Upper side of brake pedal
D. Under side of inst rument lower driver
panel
Component Function
Description
Vehicle-to-vehicle distance control mode
Conventional (fixed speed) cruise control mode Intelligent Brake Assist (IBA)
Brake Assist (with preview function)
ADAS control unit ×××× ADAS control unit calculates a target distance between vehicles
and a target speed, based on signals received from each sensor
and switch to transmit an engine torque command value to ECM
and a brake fluid pres sure control signal to ABS actuator and
electric unit (control unit) via CAN communication
 ADAS control unit transmits buzzer output signal to combination
meter via CAN communication
ICC sensor ×××× ICC sensor detects light reflected from a vehicle ahead by irra-
diating laser forward and calculates a distance from the vehicle
ahead and a relative speed, based on the detected signal
 ICC sensor transmits the presence/absence of vehicle ahead and the distance from the vehicle to ADAS control unit via ITS
communication
ECM ×××× ECM transmits the accelerator pedal position signal, ICC brake
switch signal, stop lamp switch signal, ICC steering switch sig-
nal, etc. to ADAS control unit via CAN communication
 ECM controls the electric throttle control actuator based on the engine torque demand received from the ADAS control unit via
CAN communication
ABS actuator and electric unit
(control unit) ×××× ABS actuator and electric unit (control unit) transmits the vehicle
speed signal (wheel speed), stop lamp signal and VDC/TCS/
ABS system operation condition to ADAS control unit via CAN
communication
 ABS actuator and electric unit (control unit) controls the brake, based on a brake fluid pressure control signal received from the
ADAS control unit via CAN communication
BCM ×BCM transmits the front wiper request signal to ADAS control unit
via CAN communication
TCM ××TCM transmits the signal related to A/T control to ADAS control
unit via CAN communication
Revision: 2010 May2011 QX56

CCS-10
< SYSTEM DESCRIPTION >[ICC]
COMPONENT PARTS
Component Description
INFOID:0000000006224266
× : Applicable
13. Steering angle sensor
Refer to BRC-10, "
Component Parts
Location"
14. ADAS control unit
Refer to DAS-13, "
Component Parts
Location"
A. Back side of engine room (RH) B. Front bumper (center) C. Upper side of brake pedal
D. Under side of inst rument lower driver
panel
Component Function
Description
Vehicle-to-vehicle distance control mode
Conventional (fixed speed) cruise control mode Intelligent Brake Assist (IBA)
Brake Assist (with preview function)
ADAS control unit ×××× ADAS control unit calculates a target distance between vehicles
and a target speed, based on signals received from each sensor
and switch to transmit an engine torque command value to ECM
and a brake fluid pres sure control signal to ABS actuator and
electric unit (control unit) via CAN communication
 ADAS control unit transmits buzzer output signal to combination
meter via CAN communication
ICC sensor ×××× ICC sensor detects light reflected from a vehicle ahead by irra-
diating laser forward and calculates a distance from the vehicle
ahead and a relative speed, based on the detected signal
 ICC sensor transmits the presence/absence of vehicle ahead and the distance from the vehicle to ADAS control unit via ITS
communication
ECM ×××× ECM transmits the accelerator pedal position signal, ICC brake
switch signal, stop lamp switch signal, ICC steering switch sig-
nal, etc. to ADAS control unit via CAN communication
 ECM controls the electric throttle control actuator based on the engine torque demand received from the ADAS control unit via
CAN communication
ABS actuator and electric unit
(control unit) ×××× ABS actuator and electric unit (control unit) transmits the vehicle
speed signal (wheel speed), stop lamp signal and VDC/TCS/
ABS system operation condition to ADAS control unit via CAN
communication
 ABS actuator and electric unit (control unit) controls the brake, based on a brake fluid pressure control signal received from the
ADAS control unit via CAN communication
BCM ×BCM transmits the front wiper request signal to ADAS control unit
via CAN communication
TCM ××TCM transmits the signal related to A/T control to ADAS control
unit via CAN communication
Revision: 2010 May2011 QX56

DLN-1
TRANSMISSION & DRIVELINE
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CONTENTS
DRIVELINE
TRANSFER: ATX90A
PRECAUTION ................ ...............................
6
PRECAUTIONS .............................................. .....6
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
6
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect .....................................
6
Service Notice or Precautions for Transfer ...............7
PREPARATION ............................................8
PREPARATION .............................................. .....8
Special Service Tools .......................................... ......8
Commercial Service Tools ........................................8
SYSTEM DESCRIPTION .............................10
COMPONENT PARTS ................................... ....10
Component Parts Location .................................. ....10
Component Description ...........................................11
Transfer Control Unit ...............................................11
Transfer Control Actuator ........................................11
Transfer Hi-Lo Position Sensor ...............................12
Transfer Rotary Position Sensor .............................12
Transfer Lock Position Sensor ................................12
Transfer Fluid Temperature Sensor ........................12
STRUCTURE AND OPERATION .......................13
Sectional View ..................................................... ....13
Torque Split Mechanism .........................................13
SYSTEM .............................................................18
4WD SYSTEM ...........................................................18
4WD SYSTEM : System De scription ......................18
4WD SYSTEM : Fail-Safe ......................... ..............20
DIAGNOSIS SYSTEM (TRANSFER CON-
TROL UNIT) .................................................... ....
21
CONSULT-III Function ........................................ ....21
ECU DIAGNOSIS INFORMATION ..............24
TRANSFER CONTROL UNIT ...........................24
Reference Value .................................................. ....24
Fail-Safe ..................................................................28
DTC Inspection Priority Chart ..................................29
DTC Index ...............................................................29
WIRING DIAGRAM ......................................31
4WD SYSTEM .. ................................ .................31
Wiring Diagram .................................................... ....31
BASIC INSPECTION ...................................38
DIAGNOSIS AND REPAIR WORK FLOW .......38
Work Flow ............................................................ ....38
Diagnostic Work Sheet ............................................39
ADDITIONAL SERVICE WHEN REPLACING
TRANSFER CONTROL UNIT ...........................
41
Description ...............................................................41
Work Procedure .......................................................41
ADDITIONAL SERVICE WHEN REPLACING
TRANSFER ASSEMBLY ..................................
42
Description ...............................................................42
Work Procedure .......................................................42
TRANSFER LOCK POSITION SENSOR
LEARNING ....................................... .................
44
Description ........................................................... ....44
Work Procedure .......................................................44
TRANSFER ROTARY POSITION SENSOR
LEARNING ....................................... .................
46
Description ........................................................... ....46
Work Procedure .......................................................46
TRANSFER FLUID VISCOSITY LEARNING ....47
Description ...............................................................47
Revision: 2010 May2011 QX56

PRECAUTIONSDLN-7
< PRECAUTION > [TRANSFER: ATX90A]
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5. When the repair work is completed, re-connect both battery cables. With the brake pedal released, turn
the push-button ignition switch from ACC position to ON position, then to LOCK position. (The steering
wheel will lock when the push-button ignition switch is turned to LOCK position.)
6. Perform self-diagnosis check of a ll control units using CONSULT-III.
Service Notice or Precautions for TransferINFOID:0000000006222211
CAUTION:
 Use Genuine NISSAN Transfer Fluid. Refer to MA-10, "
Fluids and Lubricants".
 Never reuse transfer fluid, once it has been drained.
 Check the fluid level or repl ace the fluid only with the vehicle parked on level ground.
 During removal or installati on, keep inside of transfer clear of dust or dirt.
 Replace all tires at the same time. Always use tir es of the proper size and the same brand and pat-
tern. Fitting improper size and unusually worn tires applies excessive force to vehicle mechanism
and can cause longitudinal vibration.
 Disassembly should be done in a clean work area, it is preferable to work in dustproof area.
 Before proceeding with disassembly, thoroughly clean the transfer. It is important to prevent the
internal parts from becoming contamin ated by dirt or other foreign matter.
 All parts should be carefully cl eaned with a general purpose, non-flammable solvent before inspec-
tion or reassembly.
 Check for the correct installation status prior to removal or disassembly. If matching marks are
required, be certain they do not interfere wit h the function of the parts when applied.
 Check appearance of the disassembled parts for damage, deformation, and unusual wear. Replace
them with a new ones if necessary.
 Gaskets, seals and O-rings should be replaced any time the transfer is disassembled.
 In principle, tighten bolts or nu ts gradually in several steps workin g diagonally from inside to out-
side. If tightening sequence is specified, use it.
 Observe the specified torque when assembling.
 Clean and flush the parts su fficiently and blow-dry them.
 Be careful not to damage sliding surfaces and mating surfaces.
 Clean inner parts with lint-free cloth or towels . Do not use cotton work gloves and rags to prevent
adhering fibers.
Revision: 2010 May2011 QX56

DLN-14
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
STRUCTURE AND OPERATION
DESCRIPTION
 Ball ramp lever operates in the direction of main shaft axis according to rotation of actuator shaft and
presses piston. Pressure is applied to each clutch and torque is transmitted.
 Shift fork operates in the direction of main shaft axis according to rotation of actuator shaft and performs
engagement and disengagement to Hi-Lo sleeve and lock sleev e of main shaft. Mode is switched between
4H ⇔4L.
AUTO MODE
 The optimum torque distribution is electronically performed for front and rear wheels according to road con-
ditions.
 Stable start without wheel spin is possible on slippery road conditions, such as on a snowy road.
 When road condition does not require 4WD driving, the st atus becomes close to rear wheel drive, which
results in better fuel efficiency and prov ides FR-like steering characteristics.
 The vehicle cornering status is judged according to information from each sensor, and the optimum torque is
distributed to front wheels for prev enting tight-corner braking symptom.
NOTE:
When there is a difference of revolution speed between the front and rear wheel the shift occasionally changes
to direct 4-wheel driving conditions aut omatically. This is not a malfunction.
4H MODE
 Torque distribution for front and rear wheels is fixed and stable start is achieved while driving on an rough,
sandy or snowy road.
4L MODE
 Large traction force is obtained due to low gear. High running ability and escaping ability are achieved.
 Switching from 4H mode to 4L mode is not possible w hen the vehicle is not stopped and A/T shift selector is
not in the neutral position.
TORQUE DISTRIBUTION DIAGRAM
JPDIE0256GB
Revision: 2010 May2011 QX56

DLN-16
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
STRUCTURE AND OPERATION
1. Transfer control unit supplies command current to transfer motor.
2. Transfer motor operates and actuator shaft rotates clockwise.
3. Shift fork operates according to rotation of actuator shaft. Sun gear and Hi-Lo sleeve are engaged.
4. Ball ramp lever operates in axial direction via cam fixed on actuator shaft according to traction torque of
transfer motor, presses piston, and thrusts multiple plate clutch.
5. Torque is transmitted to front wheels according to thrusting pressure of multiple plate clutch. NOTE:
Torque transmitted to the front wheel is determined according to the command current.
4L MODE
1. Main shaft 2. Ball lamp lever 3. Piston
4. Clutch 5. Hi-Lo sleeve 6. Sun gear
7. Shift fork 8. Actuator shaft 9. Transfer control actuator
JPDIE0278GB
Revision: 2010 May2011 QX56

DLN-20
< SYSTEM DESCRIPTION >[TRANSFER: ATX90A]
SYSTEM
4WD Warning Lamp
 Turns ON when there is a malfunction in 4WD system. 4W
D warning lamp indicates the vehicle is in fail-safe
mode.
 Also turns ON when ignition switch is turned ON, fo r the purpose of lamp check. Turns OFF approximately
for 1 second after the engine starts if system is normal.
ATP Warning Lamp
When the A/T shift selector is in P position, the vehicle may move if the transfer case in neutral. ATP warning
lamp is turned on to indicate this condition to the driver.
CONDITION FOR OPERATE WARNING BUZZER
For preventing an incorrect operation during 4H ⇔4L switching, warning buzzer sounds from inside of transfer
control unit and warns the driver, when certain conditions are satisfied.
4WD SYSTEM : Fail-SafeINFOID:0000000006303692
 If any malfunction occurs in 4WD electrical system, and control unit detects the malfunction, 4WD warning
lamp on combination meter turns ON to indicate system malfunction.
 When 4WD warning lamp is ON, vehicle changes to rear-wheel drive or shifts to 4-wheel drive (front-wheels
still have some driving torque).
Condition 4WD warning lamp
Lamp check Turns ON when ignition switch is turned ON. Turns OFF ap-
prox. 1 second after the engine start.
4WD system malfunction ON
Protection function is activated due to heavy load to transfer assem-
bly. (4WD system is not malfunctioning.) Quick blinking: 2 times/second
(Blinking in approx. 1 minute and then turning OFF)
Large difference in diameter of front/rear tires Slow blinking: 1 time/2 seconds
(Continuing to blink until turning ignition switch OFF)
Other than above (system normal) OFF
Condition Warning buzzer
4WD shift status A/T shift selector Engine speed
4H⇔4L N range 350
− 1.600 rpm OFF
Under 350 rpm or over 1.600 rpm ON
Except N range Always
Revision: 2010 May2011 QX56