2011 INFINITI QX56 sensor

REAR DISC BRAKEBR-41
< REMOVAL AND INSTALLATION >
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REAR DISC BRAKE
BRAKE PAD
BRAKE PAD : Exploded ViewINFOID:0000000006222495
BRAKE PAD : Removal and InstallationINFOID:0000000006222496
REMOVAL
WARNING:
Clean any dust from the brake caliper assembly an d brake pads with a vacuum dust collector. Never
blow with compressed air.
CAUTION:
 Never depress the brake pedal while removing th e brake pads because the piston may pop out.
 If the brake fluid or grease adheres to the brake cal iper assembly and disc rotor, quickly wipe it off.
1. Remove tires with power tool.
2. Remove upper sliding pin bolt.
3. Suspend the cylinder body with suitable wire so that the brake hose will not stretch. Then remove the
brake pads from the torque member.
CAUTION:
 Never deform the pad retainer when removing the pad retainer from the torque member.
 Never damage the piston boot.
 Never drop the brake pads and shims.
 Remember each position of the removed brake pads.
4. Perform inspection after removal. Refer to BR-42, "
BRAKE PAD : Inspection".
INSTALLATION
WARNING:
Clean any dust from the brake caliper assembly an d brake pads with a vacuum dust collector. Never
blow with compressed air.
CAUTION:
 Never depress the brake pedal while removing th e brake pads because the piston may pop out.
 If the brake fluid or grease adheres to the brake cal iper assembly and disc rotor, quickly wipe it off.
1. Cylinder body 2. Inner shim 3. Inner pad (with pad wear sensor)
4. Pad retaining 5. Torque member 6. Outer pad
7. Outer shim
: Apply PBC (Poly Butyl Cuprysil) grease or silicone-based grease.
Refer to GI-4, "
Components" for symbols not described on the above.
JPFIA0734GB
Revision: 2010 May2011 QX56

BRC-1
BRAKES
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CONTENTS
BRAKE CONTROL SYSTEM
WITH VDC
PRECAUTION ................ ...............................
5
PRECAUTIONS .............................................. .....5
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
5
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect .....................................
5
Precaution for Procedure without Cowl Top Cover ......6
Precaution for Brake System ....................................6
Precaution for Brake Control System ........................6
Precaution for Harness Repair ..................................7
PREPARATION ............................................9
PREPARATION .............................................. .....9
Commercial Service Tools .................................. ......9
SYSTEM DESCRIPTION .............................10
COMPONENT PARTS ................................... ....10
Component Parts Location .................................. ....10
Component Description ...........................................13
ABS Actuator and Electric Unit (Control Unit) .........14
Wheel Sensor and Sensor Rotor ............................14
Stop Lamp Switch ...................................................15
Steering Angle Sensor ............................................15
Yaw Rate/Side/Decel G sensor ...............................15
Brake Fluid Level Switch .........................................15
Parking Brake Switch ..............................................15
VDC OFF Switch .....................................................15
SYSTEM .............................................................16
System Description ............................................. ....16
Fail-safe ..................................................................25
Protection Function .................................................28
VDC FUNCTION .................................................... ....28
VDC FUNCTION : System Description ...................28
TCS FUNCTION ..................................................... ....31
TCS FUNCTION : System Description ....................31
ABS FUNCTION .................................................... ....32
ABS FUNCTION : System Description ....................33
EBD FUNCTION .................................................... ....34
EBD FUNCTION : System Description ....................34
HILL START ASSIST FUNCTION ......................... ....36
hill start assist FUNCTION : System Description ....36
BRAKE LIMITED SLIP DIFFERENTIAL (BLSD)
FUNCTION ............................................................. ....
37
BRAKE LIMITED SLIP DIFFERENTIAL (BLSD)
FUNCTION : System Description ............................
37
DIAGNOSIS SYSTEM [ABS ACTUATOR
AND ELECTRIC UNIT (CONTROL UNIT)] .......
40
CONSULT-III Function ............................................40
ECU DIAGNOSIS INFORMATION ..............45
ABS ACTUATOR AND ELECTRIC UNIT
(CONTROL UNIT) .............................................
45
Reference Value .................................................. ....45
Fail-safe ...................................................................47
Protection Function ..................................................50
DTC Inspection Priority Chart ..................................50
DTC Index ...............................................................51
WIRING DIAGRAM ......................................53
BRAKE CONTROL SYSTEM ...........................53
Wiring Diagram .................................................... ....53
BASIC INSPECTION ...................................60
DIAGNOSIS AND REPAIR WORK FLOW .......60
Work Flow ............................................................ ....60
Diagnostic Work Sheet ............................................61
Revision: 2010 May2011 QX56

BRC-2
ADDITIONAL SERVICE WHEN REPLACING
ABS ACTUATOR AND ELECTRIC UNIT
(CONTROL UNIT) ..............................................
63
Description ........................................................... ...63
ADJUSTMENT OF STEERING ANGLE SEN-
SOR NEUTRAL POSITION ...............................
64
Description ........................................................... ...64
Work Procedure ......................................................64
CALIBRATION OF DECEL G SENSOR ...........66
Description ........................................................... ...66
Work Procedure ......................................................66
DTC/CIRCUIT DIAGNOSIS ...................... ...68
C1101, C1102, C1103, C1104 WHEEL SEN-
SOR ................................................................. ...
68
DTC Logic ............................................................ ...68
Diagnosis Procedure ..............................................68
C1105, C1106, C1107, C1108 WHEEL SEN-
SOR ....................................................................
70
DTC Logic ............................................................ ...70
Diagnosis Procedure ..............................................70
C1109 POWER AND GROUND SYSTEM .........72
Description ........................................................... ...72
DTC Logic ...............................................................72
Diagnosis Procedure ..............................................72
C1111 PUMP MOTOR .......................................75
DTC Logic ............................................................ ...75
Diagnosis Procedure ..............................................75
C1115 WHEEL SENSOR ...................................77
DTC Logic ............................................................ ...77
Diagnosis Procedure ..............................................77
C1116 STOP LAMP SWITCH ............................79
DTC Logic ............................................................ ...79
Diagnosis Procedure ..............................................79
Component Inspection (Stop lamp Switch) ............85
Component Inspection (Stop Lamp Relay) .............86
C1118 TRANSFER CONTROL UNIT ................87
DTC Logic ............................................................ ...87
Diagnosis Procedure ..............................................87
C1120, C1122, C1124, C1126 ABS IN VALVE
SYSTEM .......................................................... ...
88
DTC Logic ............................................................ ...88
Diagnosis Procedure ..............................................88
C1121, C1123, C1125, C1127 ABS OUT
VALVE SYSTEM ................................................
90
DTC Logic ............................................................ ...90
Diagnosis Procedure ..............................................90
C1130 ENGINE SIGNAL ...................................92
DTC Logic ............................................................ ...92
Diagnosis Procedure ............................................ ...92
C1140 ACTUATOR RELAY SYSTEM ..............93
DTC Logic ............................................................ ...93
Diagnosis Procedure ...............................................93
C1142 PRESS SENSOR ...................................95
DTC Logic ............................................................ ...95
Diagnosis Procedure ...............................................95
C1143 STEERING ANGLE SENSOR ...............97
DTC Logic ............................................................ ...97
Diagnosis Procedure ...............................................97
C1144 INCOMPLETE STEERING ANGLE
SENSOR ADJUSTMENT ..................................
99
DTC Logic ............................................................ ...99
Diagnosis Procedure ...............................................99
C1145, C1146 YAW RATE/SIDE/DECEL G
SENSOR ...........................................................
100
DTC Logic ............................................................ .100
Diagnosis Procedure .............................................100
C1155 BRAKE FLUID LEVEL SWITCH ..........103
DTC Logic ............................................................ .103
Diagnosis Procedure .............................................103
Component Inspection ..........................................104
C1160 DECEL G SEN SET ..............................105
DTC Logic ............................................................ .105
Diagnosis Procedure .............................................105
C1164, C1165 CV SYSTEM .............................106
DTC Logic ............................................................ .106
Diagnosis Procedure .............................................106
C1166, C1167 SV SYSTEM .............................108
DTC Logic ............................................................ .108
Diagnosis Procedure .............................................108
C1170 VARIANT CODING ...............................110
DTC Logic ............................................................ .110
Diagnosis Procedure .............................................110
C118E ACCUMULATOR ..................................111
DTC Logic ............................................................ .111
Diagnosis Procedure .............................................111
U1000 CAN COMM CIRCUIT ...........................112
Description ........................................................... .112
DTC Logic .............................................................112
Diagnosis Procedure .............................................112
POWER SUPPLY AND GROUND CIRCUIT ....113
Description ........................................................... .113
Diagnosis Procedure .............................................113
PARKING BRAKE SWITCH .............................117
Component Function Check ................................ .117
Diagnosis Procedure .............................................117
Component Inspection ..........................................118
Revision: 2010 May2011 QX56

BRC-3
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VDC OFF SWITCH ......................................... ..119
Component Function Check ................................ ..119
Diagnosis Procedure .............................................119
Component Inspection ..........................................120
ABS WARNING LAMP ................................... ..122
Component Function Check ................................ ..122
Diagnosis Procedure .............................................122
BRAKE WARNING LAMP ...............................123
Component Function Check ................................ ..123
Diagnosis Procedure .............................................123
VDC WARNING LAMP .....................................125
Component Function Check ................................ ..125
Diagnosis Procedure .............................................125
VDC OFF INDICATOR LAMP ..........................126
Component Function Check ................................ ..126
Diagnosis Procedure .............................................126
SYMPTOM DIAGNOSIS ............................127
EXCESSIVE OPERATION FREQUENCY ...... ..127
Description .......................................................... ..127
Diagnosis Procedure .............................................127
UNEXPECTED BRAKE PEDAL REACTION ...128
Description .......................................................... ..128
Diagnosis Procedure .............................................128
THE BRAKING DISTANCE IS LONG ..............129
Description .......................................................... ..129
Diagnosis Procedure .............................................129
DOES NOT OPERATE .....................................130
Description .......................................................... ..130
Diagnosis Procedure .............................................130
BRAKE PEDAL VIBRATION OR OPERA-
TION SOUND OCCURS ...................................
131
Description .......................................................... ..131
Diagnosis Procedure .............................................131
VEHICLE JERKS DURING ..............................132
Description .......................................................... ..132
Diagnosis Procedure .............................................132
NORMAL OPERATING CONDITION ...............133
Description .......................................................... ..133
REMOVAL AND INSTALLATION .............134
WHEEL SENSOR ........................................... ..134
FRONT WHEEL SENSOR ..................................... ..134
FRONT WHEEL SENSOR : Exploded View .........134
FRONT WHEEL SENSOR : Removal and Instal-
lation ......................................................................
134
REAR WHEEL SENSOR ....................................... ..135
REAR WHEEL SENSOR : Exploded View ...........135
REAR WHEEL SENSOR : Removal and Installa-
tion ....................................................................... ..
135
SENSOR ROTOR ............................................136
FRONT SENSOR ROTOR ..................................... ..136
FRONT SENSOR ROTOR : Removal and Instal-
lation ......................................................................
136
REAR SENSOR ROTOR ....................................... ..136
REAR SENSOR ROTOR : Removal and Installa-
tion .........................................................................
136
ABS ACTUATOR AND ELECTRIC UNIT
(CONTROL UNIT) ...........................................
137
Removal and Installation .......................................137
YAW RATE/SIDE/DECEL G SENSOR ...........138
Exploded View .......................................................138
Removal and Installation .......................................138
STEERING ANGLE SENSOR .........................139
Removal and Installation .......................................139
VDC OFF SWITCH ..........................................140
Removal and Installation .......................................140
BRAKE ASSIST (WITH PREVIEW FUNC-
TION)
PRECAUTION ............... .............................
141
PRECAUTIONS ...............................................141
Precautions for Preview Function Service ........... ..141
SYSTEM DESCRIPTION ...........................142
COMPONENT PARTS ....................................142
Component Parts Location .................................. ..142
Component Description .........................................143
SYSTEM ..........................................................145
BRAKE ASSIST (WITH PREVIEW FUNCTION) ... ..145
BRAKE ASSIST (WITH PREVIEW FUNCTION) :
System Description ................................................
145
DTC/CIRCUIT DIAGNOSIS .......................146
BRAKE ASSIST (WITH PREVIEW FUNC-
TION) ...............................................................
146
Diagnosis Procedure ........................................... ..146
SYMPTOM DIAGNOSIS ............................147
NORMAL OPERATING CONDITION .............147
Description ........................................................... ..147
INTELLIGENT BRAKE ASSIST
PRECAUTION ............... .............................
148
PRECAUTIONS ...............................................148
Precautions for IBA System Service .................... ..148
Revision: 2010 May2011 QX56

PRECAUTIONSBRC-5
< PRECAUTION > [WITH VDC]
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006228174
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 Necessary for Steering Wh eel Rotation after Battery Disconnect
INFOID:0000000006228175
NOTE:
 Before removing and installing any control units, first tu rn the push-button ignition switch to the LOCK posi-
tion, then disconnect both 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 batte ry 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 wil l 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

PRECAUTIONSBRC-7
< PRECAUTION > [WITH VDC]
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and tires installed on the vehicle are the specified si ze and parts. Brake performance and controllability may
be negatively affected when other parts than the specified are installed.
 Brake stopping distance may become longer and steering stability may be negatively affected, when tires in
different size and combination or other parts than the specified are used.
 When a radio (including wiring), antenna and antenna lead line are located near ABS actuator and electric
unit (control unit), a malfunction or improper operation ma y occur for the control of VDC function, TCS func-
tion, ABS function, EBD function, hill start assist func tion or brake limited slip differential (BLSD) function.
 When the following items are replaced by other parts than genuine parts or modified, ABS warning lamp, brake warning lamp and VDC warning lamp may turn ON, and the control may not operate normally for VDC
function, TCS function, ABS function, EB D function, hill start assist function or brake limited slip differential
(BLSD) function.
- Suspension component parts (shock absorber, spring, bushing and others)
- Tire and wheel (other than the specified size)
- Brake component parts (brake pad, disc rotor, brake caliper and others)
- Engine component parts (ECM, muffler and others)
- Body reinforcement component parts (rollover bar, tower bar and others)
 When suspension, tire and brake component parts are excessively worn or deteriorated and the vehicle is
driven, ABS warning lamp, brake warning lamp and VDC warning lamp may tu\
rn ON, and the control may
not operate normally for VDC function, TCS function, ABS function, EBD function, hill start assist function or
brake limited slip differential (BLSD) function.
 ABS warning lamp, brake warning lamp and VDC warning lamp may turn ON, when only front wheel or rear wheel is rotated using a free roller. This is not a ma lfunction, because it is caused by wheel speed difference
between wheel that is rotated and wheel that is not rota ted. In this case, perform self-diagnosis, check self-
diagnosis results, and erase memory.
 When power supply voltage is not normal, ABS warning lamp, brake warning lamp and VDC warning lamp
turn ON. ABS actuator and electric unit (control unit) st ops control for VDC function, TCS function, ABS func-
tion, EBD function, hill start assist function or brake limited slip differential (BLSD) function. Ordinary brake
operates. After power supply returns to normal, ABS warning lamp, brake warning lamp and VDC warning
lamp turn OFF. The control becomes operative for VD C function, TCS function, ABS function, EBD function,
hill start assist function or brake li mited slip differential (BLSD) function.
 VDC warning lamp may turn ON and VDC function or TCS function may not normally operate, when driving
on a special road the is extremely slanted (bank in a circ uit course). This is not a malfunction if the status
returns to normal for VDC function or TCS function after the engine is started again. In this case, perform
self-diagnosis, check self-diagnosis results, and erase memory.
 A malfunction in yaw rate/side/decel G sensor syste m may be detected when the vehicle sharply turns dur-
ing a spin turn, acceleration turn or drift driving while VDC function or TCS function are OFF (VDC OFF
switch is pressed and VDC OFF indicator lamp is in ON st atus). This is not a malfunction if the status returns
to normal for VDC function or TCS function after the engine is started again. In this case, perform self-diag-
nosis, check self-diagnosis results, and erase memory
Precaution for Harness RepairINFOID:0000000006222558
 Solder the repair part, and wrap it with tape. [Twisted wire fray must be 110 mm (4.33 in) or less.]
SKIB8766E
Revision: 2010 May2011 QX56

COMPONENT PARTSBRC-11
< SYSTEM DESCRIPTION > [WITH VDC]
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4WD
1. ECM Refer to EC-16, "
Component Parts
Location". 2. Control valve & TCM
Refer to TM-10, "
A/T CONTROL
SYSTEM : Compon ent Parts Loca-
tion". 3. Front wheel sensor
4. ABS actuator and electric unit (con- trol unit) 5. Stop lamp switch 6. Steering angle sensor
7. VDC OFF switch 8. Yaw rate/side/decel G sensor 9. Rear wheel sensor
A. Front wheel hub and bearing assem- bly B. Inside engine room C. Brake pedal
D. ABS warning lamp, brake warning lamp, VDC warning lamp, VDC OFF
indicator lamp E. Back of spiral cable assembly F. Center console assembly
G. Under center console assembly H. Rear wheel hub and bearing assem- bly
Revision: 2010 May2011 QX56

BRC-12
< SYSTEM DESCRIPTION >[WITH VDC]
COMPONENT PARTS
1. Transfer control unit
Refer to DLN-10, "
Component Parts
Location". 2. ECM
Refer to EC-16, "
Component Parts
Location". 3. Control valve & TCM
Refer to TM-10, "
A/T CONTROL
SYSTEM : Component Parts Loca-
tion".
4. Front wheel sensor 5. ABS actuat or and electric unit (con-
trol unit) 6. Stop lamp switch
7. Steering angle sensor 8. VDC OFF switch 9. Yaw rate/side/decel G sensor
10. Rear wheel sensor
A. Front wheel hub and bearing assem- bly B. Inside engine room C. Brake pedal
JPFIC0186ZZ
Revision: 2010 May2011 QX56