INFINITI QX56 2011 Factory Service Manual

SB-16
< REMOVAL AND INSTALLATION >
SECOND SEAT BELT
SEAT BELT BUCKLE : Re moval and Installation
INFOID:0000000006217626
REMOVAL
1. Remove the second seat assembly from vehicle. Refer to SE-125, "Removal and Installation".
2. Remove the seat cushion and seat cushion under cover from seat cushion frame. Refer to SE-130, "
SEAT
CUSHION : Disassembly and Assembly".
3. Remove the seat belt buckle mounting anchor bolt and then remove the center and outer seat belt buckle.
INSTALLATION
Install in the reverse order of removal.
1. Anchor bolt 2. Seat belt adjuster 3. Retaining washer
4. Shoulder anchor 5. Anchor nut 6. Second seat belt retractor RH
7. Outer anchor cover 8. Outer anchor 9. Spacer
10. Retaining washer 11. Second seat belt retractor LH 12. Seat belt buckle RH
13. Seat belt buckle LH
Refer to GI-4, "
Components" for symbols in the figure.
JMHIA1496GB
Revision: 2010 May2011 QX56

THIRD SEAT BELTSB-17
< REMOVAL AND INSTALLATION >
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THIRD SEAT BELT
SEAT BELT RETRACTOR
SEAT BELT RETRACTOR : InspectionINFOID:0000000006217627
AFTER A COLLISION
WARNING:
Inspect all seat belt assemblies in cluding retractors and attached hardware after any collision.
NISSAN/INFINITI recommends that all seat belt assemblies in use during a collision be replaced
unless the collision was minor and th e belts show no damage and continue to operate properly. Fail-
ure to do so could result in serious personal inju ry in an accident. Seat belt assemblies not in use dur-
ing a collision should also be replaced if either da mage or improper operation was noted. Seat belt
pre-tensioners should be replaced even if the seat be lts were not in use during a frontal collision in
which the air bags were deployed.
Replace any seat belt assembly (including anchor bolts) if:
 The seat belt is in use at the time of a collision (exc ept for minor collisions and the belts, retractors and buck-
les show no damage and continue to operate properly).
 The seat belt is damaged in an accident (i.e. to rn webbing, bent retractor or guide, etc.).
 The seat belt attaching point is damaged in an accident . Inspect the seat belt attaching area for damage or
distortion and repair if necessary before installing a new seat belt assembly.
 Anchor bolts are deformed or worn out.
 The seat belt pre-tensioners must be replaced even if t he seat belts were not in use during the collision in
which the air bags were deployed.
PRELIMINARY CHECKS
1. Check that the seat belt retractor, seat belt anchor and buckle bolts are tightened firmly.
2. Check retractor operation:
a. Fully extend the seat belt webbing and check for twists, tears or other damage.
b. Allow the seat belt to retract. Check that webbing retu rns smoothly and completely into the retractor. If the
seat belt does not return smoothly, wipe the inside of t he loops with a clean paper cloth. Dirt build-up in the
loops of that upper anchors can cause the seat belts to retract slowly.
c. Fasten the seat belt. Check that seat belt returns sm oothly and completely to the retractor. If the webbing
does not return smoothly, the cause may be an accu mulation of dust or dirt. Use the “SEAT BELT TAPE
SET” and perform the following steps.
3. Repeat steps above if necessary to check the other seat belts.
SEAT BELT RETRACTOR ON-VEHICLE CHECK
Emergency Locking Retractors (ELR) and Automatic Locking Retractors (ALR)
NOTE:
All seat belt retractors are Emergency Locking Retr actors (ELR) type. In an emergency (sudden stop) the
retractor will lock and prevent the webbing from extendi ng any further. All 3-point type seat belt retractors
except the driver seat belt also have an Automati c Locking Retractors (ALR) mode. The ALR mode (also
called child restraint mode) is used when installing child seats. The ALR mode is activated when the seat belt
is fully extended. When the webbing is then retracted part ially, the ALR mode automatically locks the seat belt
in a specific position so the webbi ng cannot be extended any further. To c ancel the ALR mode, allow the seat
belt to fully wind back into the retractor.
Check the seat belt retractors with the following test(s ) to determine if a retractor assembly is operating prop-
erly.
ELR Function Stationary Check
Grasp the shoulder webbing and pull forward quickly. The retractor should lock and prevent the belt from
extending further.
ALR Function Stationary Check
1. Pull out the entire length of seat bel t from retractor until a click is heard.
2. Retract the webbing partially. A clicking noise should be heard as the webbing retracts indicating that the
retractor is in the Automatic Locking Retractors (ALR) mode.
Revision: 2010 May2011 QX56

SB-18
< REMOVAL AND INSTALLATION >
THIRD SEAT BELT
3. Grasp the seat belt and try to pull out the retractor. The webbing must lock and not extend any further. If it
does not operate normally, replace the retractor assembly.
4. Allow the entire length of the webbing to re tract to cancel the automatic locking mode.
ELR Function Moving Check
WARNING:
Perform the following test in a safe, open area clear of other vehicles and obstructions (for example, a
large, empty parking lot). Road surface must be p aved and dry. Never perform the following test on
wet or gravel roads or on public streets and highw ays. This could result in an accident and serious
personal injury. The driver and passenger must be prepared to brace themselves in the event that the
retractor does not lock.
1. Fasten driver seat belt. Buckle a passenger in to the seat for the belt that is to be tested.
2. Proceed to the designated safe area.
3. Drive the vehicle at approximately 16 km/h ( 10 MPH). Notify any passengers of a pending sudden stop
and the driver and passenger must be prepared to brace themselves in the event that the retractor does
not lock. Apply brakes firmly and make a very hard stop.
During stopping, seat belts should lock and not be extended. If the seat belt retractor assembly does not lock,
perform the retractor off-vehicle check.
SEAT BELT RETRACTOR OFF-VEHICLE CHECK
1. Remove the third seat belt retractor. Refer to SB-19, "SEAT BELT RETRACTOR : Removal and Installa-
tion".
2. Slowly pull out webbing while tilting the retracto r assembly forward from the mounted position without
twisting the retractor assembly as shown in the figure.
a. Outer seat belt retractor  The webbing can be pulled out when the angle (A) is 15degrees or less.
 The webbing cannot be pulled out when the angle (B) is 27
degrees or more.
b. Center seat belt retractor  The webbing can be pulled out when the angle (A) is 15
degrees or less.
 The webbing cannot be pulled out when the angle (B) is 27
degrees or more.
3. Replace the seat belt assembly if it does not operate normally.
A and B : Tilting angles : Vehicle front
JMHIA1064ZZ
A and B : Tilting angles: Vehicle front
JMHIA0522ZZ
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THIRD SEAT BELTSB-19
< REMOVAL AND INSTALLATION >
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SEAT BELT RETRACTOR : Exploded ViewINFOID:0000000006217628
SEAT BELT RETRACTOR : Removal and InstallationINFOID:0000000006217629
REMOVAL
THIRD SEAT BELT RETRACTOR
1. Operate rear seat lever or reclining lever to releas e seat lock assembly lock and to fold seat forward.
2. Remove the third seat assembly from vehicle. Refer to SE-138, "
Removal and Installation".
3. Remove the outer anchor. 1. Remove outer anchor cover.
2. Remove the outer anchor mounting anchor bolt.
1. Retaining washer 2. Spacer 3. Shoulder anchor
4. Rear seat belt finisher 5. Anchor bolt 6. Seat belt retractor (RH side)
7. Outer anchor 8. Outer anchor cover 9. Seat belt retractor (LH side)
10. Seat belt center retractor 11. Seat belt guide plate 12. Seat belt buckle (RH side)
13. Seat belt center buckle 14. Anchor nut 15. Seat belt anchor plate
16. Seat belt buckle (LH side) 17. Connector buckle
Refer to GI-4, "
Components" for symbols in the figure.
JMHIA1567GB
Revision: 2010 May2011 QX56

SB-20
< REMOVAL AND INSTALLATION >
THIRD SEAT BELT
4. Remove the rear kicking plate inner. Refer to INT-20, "KICKING PLATE INNER : Removal and Installa-
tion".
5. Remove the luggage side lower finisher (LH/RH). Refer to INT-36, "
LUGGAGE SIDE LOWER FINISHER :
Removal and Installation".
6. Remove the roof garnish. Refer to INT-29, "
Removal and Installation".
7. Remove the back pillar garnish (LH/RH). Refer to INT-37, "
BACK PILLAR GARNISH : Removal and
Installation".
8. Remove the shoulder anchor mounting anchor bolt and then remove the shoulder anchor.
9. Remove the seat belt retractor mounting anchor bolt and then remove the third seat belt retractor.
THIRD SEAT BELT CENTER RETRACTOR
1. Remove the roof garnish. Refer to INT-29, "Removal and Installation".
2. Remove headlining assembly rear clips. Refer to INT-29, "
Removal and Installation".
3. Slightly lower the headlining assembly rear and secure work space.
4. Remove the seat belt guide plate anchor bolt.
5. Remove the center seat belt retractor mounting anchor bolt and screw and then remove the center seat
belt retractor.
INSTALLATION
Install in the reverse order of removal.
SEAT BELT BUCKLE
SEAT BELT BUCKLE : InspectionINFOID:0000000006217630
AFTER A COLLISION
WARNING:
Inspect all seat belt assemblies in cluding retractors and attached hardware after any collision.
NISSAN/INFINITI recommends that all seat belt assemblies in use during a collision be replaced
unless the collision was minor and th e belts show no damage and continue to operate properly. Fail-
ure to do so could result in seri ous personal injury in an accident. Seat belt assemblies not in use dur-
ing a collision should also be re placed if either damage or improper operation was noted. Seat belt
pre-tensioners should be replaced even if the seat be lts were not in use during a frontal collision in
which the air bags were deployed.
Replace any seat belt assembly (including anchor bolts) if:
 The seat belt is in use at the time of a collision (e xcept for minor collisions and the belts, retractors and buck-
les show no damage and continue to operate properly).
 The seat belt is damaged in an accident. (i.e. to rn webbing, bent retractor or guide, etc.)
 The seat belt attaching point is damaged in an accident . Inspect the seat belt attaching area for damage or
distortion and repair if necessary before installing a new seat belt assembly.
 Anchor bolts are deformed or worn out.
 The seat belt pre-tensioner must be replaced even if t he seat belts were not in use during the collision in
which the air bags are deployed.
PRELIMINARY CHECKS
1. Check that the seat belt retractor, s eat belt anchor and buckle bolts are tightened firmly.
2. Repeat step above if necessary to check the other seat belts.
Revision: 2010 May2011 QX56

THIRD SEAT BELTSB-21
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SEAT BELT BUCKLE : Exploded ViewINFOID:0000000006398358
SEAT BELT BUCKLE : Removal and InstallationINFOID:0000000006217632
REMOVAL
Remove the center and outer seat belt buckle.
 Place seatback (LH/RH) in the folded position.
 Remove the seat belt buckle mounting anchor bolt.
INSTALLATION
Install in the reverse order of removal.
1. Retaining washer 2. Spacer 3. Shoulder anchor
4. Rear seat belt finisher 5. Anchor bolt 6. Seat belt retractor (RH side)
7. Outer anchor 8. Outer anchor cover 9. Seat belt retractor (LH side)
10. Seat belt center retractor 11. Seat belt guide plate 12. Seat belt buckle (RH side)
13. Seat belt center buckle 14. Anchor nut 15. Seat belt anchor plate
16. Seat belt buckle (LH side) 17. Connector buckle
Refer to GI-4, "
Components" for symbols in the figure.
JMHIA1567GB
Revision: 2010 May2011 QX56

SB-22
< REMOVAL AND INSTALLATION >
LATCH SYSTEM FOR CHILDREN
LATCH SYSTEM FOR CHILDREN
Exploded ViewINFOID:0000000006217633
Removal and InstallationINFOID:0000000006217634
REMOVAL
CAUTION:
Replace anchor bolts if they are deformed or worn out.
1. Remove the luggage rear plate. Refer to INT-35, "
LUGGAGE REAR PLATE : Removal and Installation".
2. Remove anchor bolt, and then remove LATCH (Low er Anchor and Tether for Children) system.
INSTALLATION
Install in the reverse order of removal.
1. Anchor bolt 2. Anchor plate 3. Retaining washer
: Vehicle front
Refer to GI-4, "
Components" for symbols in the figure.
JMHIA1484GB
Revision: 2010 May2011 QX56

SBC-1
RESTRAINTS
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SECTION SBC
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CONTENTS
SEAT BELT CONTROL SYSTEM
PRECAUTION ................ ...............................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution for Seat Belt Service ...............................3
SYSTEM DESCRIPTION ..............................5
COMPONENT PARTS ................................... .....5
Component Parts Location .................................. ......5
Component Description .............................................6
SYSTEM ..............................................................7
PRE-CRASH SEAT BELT SYSTEM ...........................7
PRE-CRASH SEAT BELT SYSTEM : System Di-
agram .................................................................. ......
7
PRE-CRASH SEAT BELT SYSTEM : System De-
scription .....................................................................
7
PRE-CRASH SEAT BELT SYSTEM : Fail Safe ........9
SEAT BELT WARNING LAMP SYSTEM ..................10
SEAT BELT WARNING LAMP SYSTEM : System
Diagram ............................................................... ....
10
SEAT BELT WARNING LAMP SYSTEM : System
Description ..............................................................
10
DIAGNOSIS SYSTEM (PRE-CRASH SEAT
BELT) .................................................................
11
CONSULT-III Function ........................................ ....11
ECU DIAGNOSIS INFORMATION ..............13
PRE-CRASH SEAT BELT CONTROL UNIT
(DRIVER SIDE) ............................................... ....
13
Reference Value ................................................. ....13
Fail Safe ..................................................................14
DTC Index ...............................................................16
PRE-CRASH SEAT BELT CONTROL UNIT
(PASSENGER SIDE) ........................................
17
Reference Value .................................................. ....17
Fail Safe ..................................................................17
WIRING DIAGRAM ......................................19
PRE-CRASH SEAT BELT SYSTEM .................19
Wiring Diagram .................................................... ....19
SEAT BELT WARNING SYSTEM ....................26
Wiring Diagram ........................................................26
BASIC INSPECTION ...................................31
DIAGNOSIS AND REPAIR WORKFLOW ........31
Work Flow ............................................................ ....31
DTC/CIRCUIT DIAGNOSIS .........................33
U0126 ST ANG SEN SIG ..................................33
Description ........................................................... ....33
DTC Logic ................................................................33
Diagnosis Procedure ...............................................33
U0428 STRG ANGL CAL ..................................34
Description ...............................................................34
DTC Logic ................................................................34
Diagnosis Procedure ...............................................34
U1000 CAN COMM CIRCUIT ...........................35
Description ...............................................................35
DTC Logic ................................................................35
B2451 SEAT BLT MTR DR CIRC .....................36
DTC Logic ................................................................36
Diagnosis Procedure ...............................................36
B2452 SEAT BLT MTR AS CIRC .....................37
DTC Logic ................................................................37
Diagnosis Procedure ...............................................37
B2453 BR STROKE SEN CIRC ........................38
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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
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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