2011 INFINITI QX56 steering

SB-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006369606
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 severi ty 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 “SRS AIR BAG” and “SEAT BELT” of this
Service Manual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision that would result in air bag inflation, all maintenance must be performed by
an authorized NISS AN/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 “SRS AIR BAG”.
 Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied 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 Air Bag Diagnosis Sensor Unit or other Air Bag System sensors with the ignition ON or engine running, DO NOT use air or electric 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:0000000006369607
NOTE:
 Before removing and installing any control units, first tu rn the push-button ignition switch to the LOCK posi-
tion, then disconnect bot h battery cables.
 After finishing work, confirm that all control unit connectors are connected properly, then re-connect both
battery cables.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If a DTC is detected, perform trouble diagnos is according to self-diagnosis results.
For vehicle with steering lock unit, if the battery is disconnected or discharged, the steering wheel will lock and
cannot be turned.
If turning the steering wheel is required with the bat tery disconnected or discharged, follow the operation pro-
cedure below before starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Turn the push-button ignition switch to ACC position. (At this time, the steering lock will be released.)
3. Disconnect both battery cables. The steering lock wi ll remain released with both battery cables discon-
nected and the steering wheel can be turned.
4. Perform the necessary repair operation.
Revision: 2010 May2011 QX56

PRECAUTIONSSB-3
< PRECAUTION >
C
DE
F
G
I
J
K L
M A
B
SB
N
O P
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.
Precaution for Seat Belt ServiceINFOID:0000000006217608
CAUTION:
 Before removing the front seat belt pre-tensioner assembly, turn the ignition switch off, disconnect
battery negative terminal and wait at least 3 minutes.
 Never use electrical test equipment for front seat belt pre-tensioner connector.
 After replacing or reinstalling front seat belt pre-tensioner assembly, or reconnecting front seat belt
pre-tensioner connector, check th e system function. Refer to SRC-14, "
Description".
 Never use disassembled buckle or seat belt assembly.
 Replace anchor bolts if th ey are deformed or worn out.
 Never oil tongue and buckle.
 If any component of seat belt assembly is questiona ble, do not repair. Replace the entire seat belt
assembly.
 If webbing is cut, frayed or damaged, replace seat belt assembly.
 When replacing seat belt assembly, u se a genuine NISSAN seat belt assembly.
AFTER A COLLISION
WARNING:
Inspect all seat belt assemblies including retractors and attached hardware after any collision.
NISSAN recommends that all seat belt assemblies in u se during a collision be replaced unless the col-
lision was minor and the belts show no damage a nd continue to operate properly. Failure to do so
could result in serious personal injury in an accide nt. Seat belt assemblies not in use during a colli-
sion should also be replaced if either damage or im proper operation is noted. Seat belt pre-tensioners
should be replaced even if the seat belts are not in use during a frontal collision in which the air bags
are deployed.
Replace any seat belt assembly (including anchor bolts) if:
 The seat belt was in use at the time of a collision (except for minor collisions and the belts, retractors and
buckles show no damage and continue to operate properly).
 The seat belt was damaged in an accident (i.e. torn webbing, bent retractor or guide).
 The seat belt attaching point was damaged in an accident. Inspect the seat belt attaching area for damage or distortion and repair as necessary before installing a new seat belt assembly.
 Anchor bolts are deformed or worn out.
 The front seat belt pre-tensioner should be replaced even if the seat belts are not in use during the collision
in which the air bags are deployed.
Revision: 2010 May2011 QX56

COMPONENT PARTSSBC-5
< SYSTEM DESCRIPTION >
C
DE
F
G
I
J
K L
M A
B
SBC
N
O P
SYSTEM DESCRIPTION
COMPONENT PARTS
Component Parts LocationINFOID:0000000006237875
1. BCM Refer to BCS-4, "
BODY CONTROL
SYSTEM : Componen t Parts Loca-
tion". 2. Combination meter
Refer to MWI-6, "
METER SYSTEM :
Component Parts Location". 3. ABS actuator and electric unit (con-
trol unit)
Refer to BRC-149, "Component
Parts Location".
4. Brake pedal stroke sensor 5. Steering angle sensor Pre-crash 6. Pre-crash seat belt control unit (driver side)
7. ADAS control unit Refer to DAS-13, "
Component Parts
Location". 8. Air bag diagnosis sensor unit
Refer to SRC-8, "
Component Parts
Location". 9. Seat belt control unit (passenger
side)
10. Seat belt buckle switch
JMHIA1582ZZ
Revision: 2010 May2011 QX56

SBC-6
< SYSTEM DESCRIPTION >
COMPONENT PARTS
Component Description
INFOID:0000000006237876
A. View with instrument driver lower cov- er removed B. Combination switch C. View with center pillar lower garnish
removed (driver side)
D. View with center pillar lower garnish re- moved (passenger side)
Component Function
ABS actuator and electric unit (control unit) ABS operation signal is rece
ived from ABS actuator and el ectric unit (control unit)
via CAN communication.
ADAS control unit Intelligent brake assistance operation signal is received from ADAS control unit
via CAN communication.
Air bag diagnosis sensor unit  Detects a collision and supplies power supply for deployment to air bag module
and pre-tensioner seat belt.
 Performs the deploy judgement of passenger air bag based on the information from Occupant Detection System control unit
BCM Ignition ON signal, sleep/wake up signal, and door switch signal are received
from BCM via CAN communication.
Brake pedal stroke sensor  It changes voltage according to brake pedal depressed amount and sends the
signal to pre-crash seat belt control unit.
 There are 2 signals (brake pedal stroke sensor 1 and 2) sent from the brake
pedal stroke sensor. Pre-crash seat belt control unit judges the stroke amount
and the speed of the brake pedal according to the voltage of the signal sent by
each side.
Combination meter  Transmits vehicle speed signal to pre-crash seat belt control unit (driver side).
 Turns the seat belt warning lamp ON when the seat belt is unfastened.
Occupant detection system control unit Judges the passenger seat condition based on the information from occupant de-
tection unit.
Pre-crush seat belt control unit (driver side)  Total control of pre-crash seat belt system is operated according to transmit sig-
nal.
 Driver seat belt retractor integrates pre-crash seat belt control unit (driver side), driver seat belt motor, and tension reducer.
 Seat belt motor operates each operation of pull, return, and hold.
Pre-crush seat belt control unit (passenger side)  Control of passenger pre-crash seat belt is operated according to transmit sig-
nal.
 Passenger seat belt retractor integrates pre-crash seat belt control unit (driver seat), driver seat belt motor, and tension reducer.
 Seat belt motor operates each operation of pull, return, and hold.
Seat belt buckle switch (driver side)  Fastening or not fastening of seat belt is judged. This judgment is used for con-
trol of driver pre-crash seat belt system.
 Seat belt warning lamp on combination meter turns ON when seat belt is not fastened while ignition switch is ON.
 The seat belt buckle switch is installed in the seat belt buckle.
Seat belt buckle switch (passenger side)  Fastening or not fastening of seat belt is judged. This judgment is used to con-
trol passenger pre-crash seat belt system.
 The seat belt buckle switch is installed in the seat belt buckle.
Steering angle sensor Steering angle sensor signal, steering angle speed signal, steering angle sensor
neutral position adjustment completion signal, and steering angle sensor mal-
function signal are received via CAN communication.
Revision: 2010 May2011 QX56

SYSTEMSBC-7
< SYSTEM DESCRIPTION >
C
DE
F
G
I
J
K L
M A
B
SBC
N
O P
SYSTEM
PRE-CRASH SEAT BELT SYSTEM
PRE-CRASH SEAT BELT SYSTEM : System DiagramINFOID:0000000006237877
PRE-CRASH SEAT BELT SYSTEM : System DescriptionINFOID:0000000006237878
 Pre-crash seat belt system integrates control unit and motor in driver and passenger seat belt retractors.
 Provides a sense of ease when pre-crash seat belt c ontrol unit judges the emergency braking operation, the
intelligent brake assistance operating status, the c ontinuous ABS operating status, the emergency steering
wheel operation, the excessive vehicle inclination stat us, or the lateral slippage status during cornering.
The motor immediately retracts the seat belt and suppresses change in occupant posture.
 Even in a situation where a collision is unavoidable, effe cts of other safety devices, like the air bag, are max-
imized and damages are reduced.
 Motor retracts seat belt when unfastening and extrac ts seat belt when fastening to reduce the feeling of
pressure. (comfort function)
FUNCTION DESCRIPTION
Pre-crash seat belt system operat es under the following conditions.
 During emergency brake operation
 When ABS continuously operates
 When intelligent brake assistance operates
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
JMHIA1565GB
Revision: 2010 May2011 QX56

SBC-8
< SYSTEM DESCRIPTION >
SYSTEM
 When the vehicle inclined excessively
 When comfort function operates
OPERATION CONDITION
Operation while driving
 Operation start and stop conditions of pre-crash seat belt system are as shown in the following table.
 The activation and deactivation conditions of pre-crush seat belt are as per the following.
NOTE:
For details of intelligent brake assist system.Refer to BRC-152, "
INTELLIGENT BRAKE ASSIST : System
Description".
Comfort function
 Seat belt is retracted and the looseness is reduced in the state as shown in the following table.
 Operation start and stop conditions of pre-crash seat belt system are as shown in the following table.
Operation Prohibition Condition
Pre-crash seat belt system does not operate in the following conditions.
 When seat belt is not fastened (only the seat belt that is not fastened does not operate)
 When motor is overheat due to contentious operation*1
 When the system is in fail-safe mode *1: System operation is temporarily deactivated to av oid overheating, when comfort function is continuously
operated (18 times or more) during a short period of time by fastening and unfastening seat belts or opening
and closing doors.
MALFUNCTION WARNING
When system malfunction is detected, comfort function is deactivated to warn customer of system malfunc-
tion.
Operation item Operation start condition Operation stop condition
During emergency brake operation  Vehicle speed is 15 km/h (9 MPH) or more
 Emergency braking status is detected
 During acceleration
 When stopped
When ABS continuously operates  ABS continuously operates for 2 seconds or
more
 Brake pedal is in depressed state
When intelligent brake assistance oper-
ates System detects that intelligent brake assistance is
in operating status
2 seconds after operation start
When lateral slippage during cornering
occurs  Vehicle speed is 30 km/h (19 MPH) or more
 System detects that the vehicle is in lateral slip-
page state
 System detects that the vehicle is driving on a curve  Vehicle stopped
 1 second or more after maintaining
steering wheel angle in straight driv-
ing state
When steering wheel is rotated for emer-
gency  Vehicle speed is 60 km/h (36 MPH) or more
 Steering wheel angle is 90 degrees or more
 System detects that steering wheel is rotated for
emergency
When the vehicle inclined excessively  Vehicle speed is 30 km/h (19 MPH) or more
 System detects that the vehicle inclined exces-
sively  During acceleration
 Vehicle stopped
Operation item Activating condition Deactivating condition
Door open  Seat belt is in not fastened state
 Door is operated to open from closed
 Vehicle stopped  Seat belt retract is complete
 13 seconds after start retracting
Seat belt is fastened  When door is closed
 Seat belt is fastened  Seat belt is unfastened
 1 second after operation
Seat belt is release Seat belt is unfastened  Seat belt retract is complete
 10 seconds after start retracting
Revision: 2010 May2011 QX56

SYSTEMSBC-9
< SYSTEM DESCRIPTION >
C
DE
F
G
I
J
K L
M A
B
SBC
N
O P
PRE-CRASH SEAT BELT SYSTEM : Fail SafeINFOID:0000000006237879
 When a system malfunction is detected, deactivates a part of the system or all functions depending on the
malfunctioning part.
 When the malfunction condition recovers to the norma l condition, the system returns to the normal opera-
tion.
*1: The deactivation mode differs depending on the internal malfunctioning condition of control unit Display contents of CONSULT-III Fail-safe
U0126 STRG ANG SEN SIG Stops the operation in the conditions as per the following.
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 A part of comfort function
U0428 STRG ANGL CAL Stops the operation in the conditions as per the following.
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 A part of comfort function
U1000 CAN communication circuit Stops the operation in the conditions as per the following. *
1
 During emergency brake operation
 When ABS continuously operates
 When lateral slippage during cornering occurs
 When Intelligent brake assistance operates
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2451 SEAT BLT MTR DR CIRC Fully deactivates the whole operation.
B2452 SEAT BLT MTR AS CIRC Deactivate s a part of comfort function.
B2453 BR_STROKE_SEN_CIRC Stops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuously operates
 A part of comfort function
B2454 SEAT BLT PWR DR CIRC Fully deactivates the whole operation.
B2455 CONTROL UNIT DR Stops the operation in the conditions as per the following. *
1
 During emergency brake operation
 When ABS continuously operates
 When lateral slippage during cornering occurs
 When Intelligent brake assistance operates
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 A part or the whole comfort function
B2456 SEAT BLT PWR AS Deactivates a part of comfort function.
B2457 CONTROL UNIT AS Deactivates a part of comfort function.
B2458 LOCAL COMM Deactivates a part of comfort function.
B2461 VHCL SPEED SIGNAL Stops the operation in the conditions as per the following.
 During emergency brake operation
 When ABS continuously operates
 When lateral slippage during cornering occurs
 When steering wheel is rotated for emergency
 When the vehicle inclined excessively
 When comfort function operates
B2463 ROLLOVER SIGNAL Stops the operation in the conditions as per the following.
 When the vehicle inclined excessively
 A part or the whole comfort function
B2466 DR/AS CONTROL UNIT Deactivates a part of comfort function.
B2470 SYS HEAT PROTC DR  Fully deactivates the whole operation.
 Operation return
- 1 time operation becomes possible after approximately 30 seconds
- Returns to the initial condition after approximately 8 minutes
Revision: 2010 May2011 QX56

DIAGNOSIS SYSTEM (PRE-CRASH SEAT BELT)SBC-11
< SYSTEM DESCRIPTION >
C
DE
F
G
I
J
K L
M A
B
SBC
N
O P
DIAGNOSIS SYSTEM (P RE-CRASH SEAT BELT)
CONSULT-III FunctionINFOID:0000000006237882
Diagnosis for pre-crash seat belt syst em can be performed using CONSULT-III.
APPLICATION ITEM
SELF-DIAGNOSIS RESULTS
Refer to SBC-16, "DTC Index".
CAUTION:
When malfunctions are detect ed in several systems, includin g CAN communication [U1000], trouble-
shoot CAN communication [U1000].
A malfunction of system may be disp layed when battery voltage is low (when 7 to 8 V is continued for
approximately 2 seconds) even though the system is not malfunctioning. Erase DTC memory and
never replace any parts after making sure that the syst em is normal, especially if the malfunctions are
displayed after replacing battery.
ERASING SELF-DIAGNOSIS RESULTS
 SELF-DIAGNOSIS RESULTS Current “SELF-DIAG RESULTS” are displayed. (If all suspect circuits have been repaired, “NO DTC” is dis-
played.)
DATA MONITOR
Part to be diagnosed Diagnosis Mode Function description
Pre-crash seat belt Self-diagnosis Results
 Displays data recorded when a malfunction is de-
tected.
 Erases DTC recorded in memory.
Data Monitor Displays input data for pre-crash seat belt control
unit in real time.
Work Support Changes the setting for each system function.
CAN DIAG SUPPORT MNTR Monitors communication status of CAN communi-
cation.
Ecu Identification Displays pre-crash seat belt control unit part num-
ber.
Monitor item Contents
BUCKLE SW RH Indicates [ON/OFF] condition of seat belt buckle switch (RH).
BUCKLE SW LH Indicates [ON/OFF] condition of seat belt buckle switch (LH).
VEHICLE DISTANCE Indicates [ON/OFF] condit ion of intelligent brake assist signal.
IGN SW Indicates [ON/OFF] condition of ignition switch.
FR DOOR SW RH Indicates [Close/Open] condition of front door switch (RH).
FR DOOR SW LH Indicates [Close/Open] condition of front door switch (LH).
ABS ACTIVATING Indicates [ON/OFF] co ndition of ABS operation signal.
VHCL SPEED Indicates [Km/h] vehicle speed signal.
BRK PEDAL SNSR1 Indicates [V] voltage of brake pedal stroke sensor 1 signal.
BRK PEDAL SNSR2 Indicates [V] voltage of brake pedal stroke sensor 2 signal.
STRG ANGLE Indicates [deg] steering angle signal.
STRG ANGLE SPEED Indicates [deg/s] steering angle speed signal.
INCLINATION JDMT Indicates [ON/OFF] condition of pre roll over signal.
PRE-TEN ACTIVTN Indicates [ON/OFF] condition of pre-tensioner operated signal.
HEAT PROTC RH Indicates [ON/OFF] condition of heat protection (RH).
HEAT PROTC LH Indicates [ON/OFF] condition of heat protection (LH).
Revision: 2010 May2011 QX56