2011 INFINITI QX56 sensor

RSU-16
< REMOVAL AND INSTALLATION >
FRONT LOWER LINK
2. Hook spring balance (A) at groove. Confirm spring balancemeasurement value is within specifications when ball stud
begins moving.
 If swing torque exceeds the standard range, replace front lower link.
Rotating Torque Inspection
1. Move the ball joint at least ten times by hand to check for smooth movement.
2. Check that rotating torque is within the specifications.
 If rotating torque exceeds the standar d range, replace front lower link.
Axial End Play Inspection
1. Move the ball joint at least ten times by hand to check for smooth movement.
2. Move tip of ball stud in axial direction to check for looseness.
 If axial end play exceeds the standard range, replace front lower link.
INSPECTION AFTER INSTALLATION
1. Check wheel alignment. Refer to RSU-6, "Inspection".
2. Adjust neutral position of steering angle sensor. Refer to BRC-64, "
Work Procedure".
Swing torque : Refer to
RSU-20, "
Ball Joint".
JPEIA0005ZZ
Rotating torque : Refer to RSU-20, "Ball Joint".
Axial end play : Refer to RSU-20, "
Ball Joint".
Revision: 2010 May2011 QX56

RSU-18
< UNIT REMOVAL AND INSTALLATION >
REAR SUSPENSION MEMBER
UNIT REMOVAL AND INSTALLATION
REAR SUSPENSION MEMBER
Exploded ViewINFOID:0000000006225676
Removal and InstallationINFOID:0000000006225677
REMOVAL
1. Reduce system pressure. (With HBMC) Refer to SCS-18, "Work Procedure".
CAUTION:
Inadvertent piping removal causes fluid to splatter.
2. Remove tires with power tool. Refer to WT-64, "
Removal and Installation".
3. Remove emergency tires.
4. Remove front tube and main muffler. Refer to EX-5, "
Removal and Installation".
5. Remove caliper assembly. Hang caliper assembly in a place where it will not interfere with work. Refer to BR-43, "
BRAKE CALIPER ASSEMBLY : Removal and Installation".
CAUTION:
Avoid depressing brake pedal wh ile brake caliper is removed.
6. Remove disc rotor. Refer to RAX-7, "
Removal and Installation".
7. Remove wheel sensor harness from rear suspension member. Refer to BRC-135, "
REAR WHEEL SEN-
SOR : Removal and Installation".
8. Remove height sensor from rear lower link (right side). Refer to EXL-136, "
Removal and Installation".
9. Remove vehicle height sensor from rear lower link (left side). Refer to SCS-98, "
Removal and Installa-
tion".
10. Remove parking brake cable mounting bolt and separa te parking brake cable from vehicle and rear sus-
pension member. Refer to PB-5, "
Removal and Installation".
11. Remove shock absorber mounting bolt (lower side).
12. Remove stabilizer bar. (Without HBMC). Refer to RSU-17, "
Removal and Installation".
13. Remove rear lower link and coil spring. Refer to RSU-8, "
Removal and Installation".
14. Remove drive shaft. Refer to RAX-11, "
Removal and Installation".
15. Remove propeller shaft. Refer to DLN-137, "
Removal and Installation" (2WD), DLN-144, "Removal and
Installation" (4WD).
1. Rear suspension member
Refer to GI-4, "
Components" for symbols in the figure.
JPEIB0218GB
Revision: 2010 May2011 QX56

REAR SUSPENSION MEMBERRSU-19
< UNIT REMOVAL AND INSTALLATION >
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16. Remove final drive. Refer to DLN-201, "Removal and Installation".
17. Remove rear tube assembly A and rear tube assembly B. (With HBMC) Refer to SCS-44, "
REAR TUBE
ASSEMBLY : Removal and Installation".
18. Set suitable jack under rear suspension member.
19. Slowly lower jack, then remove rear suspension member, suspension arm, front lower link, wheel hub and housing from vehicle as a unit.
20. Remove mounting bolts and nuts, then remove suspension arm, front lower link, wheel hub and housing from rear suspension member.
21. Perform inspection after removal. Refer to RSU-19, "
Inspection and Adjustment".
INSTALLATION
Note the following, and install in the reverse order of the removal.
 Perform the final tightening of each of parts under unladen conditions, which were removed when removing
rear suspension assembly.
 Perform inspection after installation. Refer to RSU-19, "
Inspection and Adjustment".
 Perform adjustment after installation. (With HBMC) Refer to RSU-19, "
Inspection and Adjustment".
Inspection and AdjustmentINFOID:0000000006225678
INSPECTION AFTER REMOVAL
Check rear suspension member for deformation, cracks, or any other damage. Replace if necessary.
INSPECTION AFTER INSTALLATION
1. Adjust parking brake operation (stroke). Refer to PB-3, "Inspection and Adjustment".
2. Check wheel alignment. Refer to RSU-6, "
Inspection".
3. Adjust neutral position of steering angle sensor. Refer to BRC-64, "
Work Procedure".
4. Adjust levelizer adjustment of height sensor. Refer to EXL-61, "
LEVELIZER ADJUSTMENT : Special
Repair Requirement".
5. Check standard vehicle height setting of vehicle height sensor. Refer to SCS-67, "
Work Procedure".
6. Check wheel sensor harness for proper connection. Refer to BRC-135, "
REAR WHEEL SENSOR :
Exploded View"
ADJUSTMENT AFTER INSTALLATION (WITH HBMC)
Bleed air from the HBMC. Refer to SCS-18, "Work Procedure".
Revision: 2010 May2011 QX56

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

SBC-2
DTC Logic ...............................................................38
Diagnosis Procedure ..............................................38
Component Inspection ............................................39
B2454 SEAT BLT PWR DR CIRC .....................41
DTC Logic ............................................................ ...41
Diagnosis Procedure ..............................................41
B2455 CONTROL UNIT DR ..............................42
DTC Logic ............................................................ ...42
Diagnosis Procedure ..............................................42
B2456 SEAT BLT PWR AS ...............................43
DTC Logic ............................................................ ...43
Diagnosis Procedure ..............................................43
B2457 CONTROL UNIT AS ...............................44
DTC Logic ............................................................ ...44
Diagnosis Procedure ..............................................44
B2458 LOCAL COMM .......................................45
DTC Logic ............................................................ ...45
Diagnosis Procedure ..............................................45
B2461 VHCL SPEED SIGNAL ..........................47
Description ........................................................... ...47
DTC Logic ...............................................................47
Diagnosis Procedure ..............................................47
B2463 ROLLOVER SIGNAL .............................48
Description ........................................................... ...48
DTC Logic ...............................................................48
Diagnosis Procedure ..............................................48
B2466 DR/AS CONTROL UNIT ........................49
DTC Logic ............................................................ ...49
Diagnosis Procedure ..............................................49
B2470 SYS HEAT PROTC DR ..........................50
Description ........................................................... ...50
DTC Logic ...............................................................50
Diagnosis Procedure ..............................................50
B2471 SYS HEAT PROTC AS ..........................51
Description ........................................................... ...51
DTC Logic ...............................................................51
Diagnosis Procedure ............................................ ...51
POWER SUPPLY AND GROUND CIRCUIT .....52
Diagnosis Procedure ............................................ ...52
SEAT BELT BUCKLE SWITCH (DRIVER
SIDE) ..................................................................
53
Component Function Check ................................ ...53
Diagnosis Procedure ...............................................53
Component Inspection [Seat Belt Assembly (Driv-
er Side)] ..................................................................
54
SEAT BELT BUCKLE SWITCH (PASSEN-
GER SIDE) .........................................................
55
Component Function Check ................................ ...55
Diagnosis Procedure ...............................................55
Component Inspection [Seat Belt Assembly (Pas-
senger Side)] ...........................................................
56
SEAT BELT WARNING LAMP CIRCUIT ..........57
Component Function Check ................................ ...57
Diagnosis Procedure ...............................................57
Component Inspection [Seat Belt Assembly (Pas-
senger Side)] ...........................................................
58
SYMPTOM DIAGNOSIS ............................60
PRE-CRASH SEAT BELT DOSE NOT OPER-
ATE ................................................................. ...
60
Diagnosis Procedure ............................................ ...60
SEAT BELT WARNING LAMP DOES NOT
TURN OFF .........................................................
61
Diagnosis Procedure ............................................ ...61
SEAT BELT WARNING LAMP DOES NOT
TURN ON ...........................................................
62
Diagnosis Procedure ............................................ ...62
REMOVAL AND INSTALLATION ..............63
BRAKE PEDAL STROKE SENSOR .............. ...63
Exploded View ..................................................... ...63
Removal and Installation .........................................63
Revision: 2010 May2011 QX56

PRECAUTIONSSBC-3
< PRECAUTION >
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006237873
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 whether 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 inoper ative, which could increase the risk of personal injury or death in
the event of a collision that would result in air ba g 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 unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SRS AIR BAG”.
 Do not use electrical test equipm ent 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 minutes before performing any service.
Precaution for Seat Belt ServiceINFOID:0000000006237874
CAUTION:
 Before removing the seat belt pre-tensioner assembly, turn the ignition switch off, disconnect the
both battery cables and wait at least 3 minutes.
 Do not use electrical test equipment for seat belt pre-tensioner connector.
 After replacing or reinstalling seat belt pre-tens ioner assembly, or reconnecting front seat belt pre-
tensioner connector, check the system function. Refer to SRC-11, "
System Diagram".
 Do not use disassemble 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 questio nable, do not repair. Replace the whole 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 attaching 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-tensioner
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:
Revision: 2010 May2011 QX56

COMPONENT PARTSSBC-5
< SYSTEM DESCRIPTION >
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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