warning INFINITI QX56 2011 Factory Owner's Guide

HYDRAULIC BOOSTER ASSEMBLYBR-15
< PERIODIC MAINTENANCE >
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HYDRAULIC BOOSTER ASSEMBLY
InspectionINFOID:0000000006222467
OPERATION CHECK
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Check that the fluid level in the reservoir tank is MAX line.
4. Position the selector lever in P range to release the parking brake.
5. Turn the ignition switch ON to check the time between motor activation and motor stop.
6. After the motor is stopped, check that the ABS warning lamp and the VDC warning lamp in the combina- tion meter are OFF when the engine is started.
7. Stop the engine (ignition switch OFF).
8. Turn the ignition switch ON and depress the brake pedal 4 to 5 times to check the time between motor activation and motor stop.
9. Turn the ignition switch OFF. Turn the ignition switch ON again. Check that the VDC warning lamp turns ON when the brake pedal is depressed 15 to 20 times.
10. Check that the VDC warning lamp turns ON when the brake pedal is depressed 15 to 20 times after the lapse of 120 seconds or more after the ignition switch is turned ON again.
11. Perform the self-diagnosis for “ABS” with CONSULT-III and erase self-diagnosis results.
FUNCTION CHECK
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more.
NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Turn the ignition switch ON with the brake pedal depr essed to check that the clearance between the brake
pedal and the dash lower panel decreases. Motor operating time : 18 seconds or less
Motor operating time : 2
− 11 seconds
Revision: 2010 May2011 QX56

BR-32
< REMOVAL AND INSTALLATION >
HYDRAULIC BOOSTER ASSEMBLY
 Apply new brake fluid to grommet of between reservoir tank and grommet and ABS actuator and electric unit
(control unit).
Inspection and AdjustmentINFOID:0000000006222486
ADJUSTMENT BEFORE INSTALLATION
Input Rod Length adjustment
1. Loosen the lock nut (1) and adjust the input rod (2) to the speci-
fied length (A).
2. Tighten the lock nut to the specified torque.
INSPECTION AFTER INSTALLATION
Operation Check
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more. NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Check that the fluid level in the reservoir tank is MAX line.
4. Position the selector lever in P range to release the parking brake.
5. Turn the ignition switch ON to check the time between motor activation and motor stop.
6. After the motor is stopped, check that the ABS warn ing lamp and the VDC warning lamp in the combina-
tion meter are OFF when the engine is started.
7. Stop the engine (ignition switch OFF).
8. Turn the ignition switch ON and depress the brake pedal 4 to 5 times to check the time between motor activation and motor stop.
9. Turn the ignition switch OFF. Turn the ignition swit ch ON again. Check that the VDC warning lamp turns
ON when the brake pedal is depressed 15 to 20 times.
10. Check that the VDC warning lamp turns ON when the brake pedal is depressed 15 to 20 times after the lapse of 120 seconds or more after the ignition switch is turned ON again.
11. Perform the self-diagnosis for “ABS” with CONSULT- III and erase all the stored self-diagnosis results.
Function Check
1. Turn the ignition switch OFF.
2. Depress the brake pedal 20 times or more.
NOTE:
The pressure loss in the accumulator results in a large brake pedal stroke. In addition to this, the brake
pedal depression becomes lighter in initial stage.
3. Turn the ignition switch ON with the brake pedal depr essed to check that the clearance between the brake
pedal and the dash lower panel decreases. A : Refer to
BR-47, "
Brake Booster".
JPFIA0728ZZ
Motor operating time : 18 seconds or less
Motor operating time : 2 − 11 seconds
Revision: 2010 May2011 QX56

BR-34
< REMOVAL AND INSTALLATION >
FRONT DISC BRAKE
FRONT DISC BRAKE
BRAKE PAD
BRAKE PAD : Exploded ViewINFOID:0000000006222488
BRAKE PAD : Removal and InstallationINFOID:0000000006222489
REMOVAL
WARNING:
Clean any dust from the brake caliper assembly and 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 calip er assembly and disc rotor, quickly wipe it off.
1. Remove tires with power tool.
2. Remove lower sliding pin bolt.
3. Suspend the cylinder body with suitable wire so that the brake hose will not stretch.
4. Remove the pad return springs (1). Then remove brake pads, shims and shim covers.
CAUTION:
1. Outer shim cover 2. Outer shim 3. Outer pad
4. Torque member 5. Pad retainer 6. Pad return spring
7. Inner pad (with pad wear sensor) 8. Inner shim 9. Inner shim cover
10. Cylinder body
: Apply MOLYKOTE
® AS880N or silicone-based grease.
Refer to GI-4, "
Components" for symbols not described on the above.
JPFIA0796GB
JPFIA0797ZZ
Revision: 2010 May2011 QX56

FRONT DISC BRAKEBR-35
< REMOVAL AND INSTALLATION >
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 Never deform the pad retainer when removing the pad retainers (2) from the torque member (1).
 Never damage the piston boot.
 Never drop the brake pads, shims and shim covers.
 Remember each position of the removed brake pads.
5. Perform inspection after removal. Refer to BR-36, "
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. Install the torque member if the pad retainers has been removed. CAUTION:
 Securely assemble the pad retainers (1) so that it will notbe lifted up from the torque member (2).
 Never deform the pad retainers.
2. Apply MOLYKOTE
® AS880N or silicone-based grease mating
faces (A and B) between the brake pad, shim and shim cover,
and install shim and shim cover to the brake pad.
CAUTION:
Always replace the shims and shim covers when replacing
the brake pad.
3. Install the brake pads to the torque member.
4. Install pad return springs (1). CAUTION:
Correctly insert the pad return spring into the pad return
spring hole on the brake pad.
5. Install cylinder body to torque member. CAUTION:
 Never damage the piston boot.
 When replacing brake pad with new one, check a brakefluid level in the reservoir tank because brake fluid
returns to reservoir tank when pressing piston in.
NOTE:
Use a disc brake piston tool to easily press piston.
6. Install lower sliding bolt and tighter it to the specified torque.
JPFIA0118ZZ
PFIA0763J
JPFIA0798ZZ
JPFIA0797ZZ
Revision: 2010 May2011 QX56

FRONT DISC BRAKEBR-37
< REMOVAL AND INSTALLATION >
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BRAKE CALIPER ASSEMBLY : Removal and InstallationINFOID:0000000006222492
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 spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never depress the brake pedal. Brake fluid m ay splash while removing the brake hose.
 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. Fix the disc rotor using wheel nuts.
3. Drain brake fluid. Refer to BR-10, "
Draining".
4. Separate brake hose from brake caliper assembly. Refer to BR-23, "
FRONT : Removal and Installation".
5. Remove torque member mounting bolts, and remove brake caliper assembly. CAUTION:
Never drop brake pad and brake caliper assembly.
6. Remove disc rotor. Refer to FA X - 8 , "
Removal and Installation" (2WD), FAX-18, "Removal and Installation"
(AWD).
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 spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never depress the brake pedal. Brake fluid m ay splash while removing the brake hose.
 If the brake fluid or grease adheres to the brake cal iper assembly and disc rotor, quickly wipe it off.
1. Torque member 2. Sliding pin boot 3. Sliding pin
4. Piston boot 5. Piston 6. Piston seal
7. Cylinder body 8. Bleeder valve 9. Cap
: Apply rubber grease.
: Apply brake fluid.
Refer to GI-4, "
Components" for symbols not described on the above.
JPFIA0800GB
Revision: 2010 May2011 QX56

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

REAR DISC BRAKEBR-43
< REMOVAL AND INSTALLATION >
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DISASSEMBLY
BRAKE CALIPER ASSEMBLY : Removal and InstallationINFOID:0000000006222499
REMOVAL
WARNING:
Clean any dust from the brake caliper assembly an d brake pads with a vacuum dust collector. Never
blow with compressed air.
1. Brake caliper assembly
Refer to GI-4, "
Components" for symbols in the figure.
JPFIA0735GB
1. Cap 2. Bleeder valve 3. Cylinder body
4. Piston seal 5. Piston 6. Piston boot
7. Sliding pin 8. Bushing 9. Sliding pin boot
10. Torque member
: Apply rubber grease.
: Apply brake fluid
Refer to GI-4, "
Components" for symbols not described on the above.
JPFIA0736GB
Revision: 2010 May2011 QX56

BR-44
< REMOVAL AND INSTALLATION >
REAR DISC BRAKE
CAUTION:
 Never spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never depress the brake pedal. Brake fluid may splash while removing the brake hose.
 If the brake fluid or grease adheres to the brake calip er assembly and disc rotor, quickly wipe it off.
1. Remove tires with power tool.
2. Fix the disc rotor using wheel nuts.
3. Drain brake fluid. Refer to BR-10, "
Draining".
4. Separate brake hose from brake caliper assembly. Refer to BR-26, "
REAR : Removal and Installation".
5. Remove torque member mounting bolts, and remove brake caliper assembly. CAUTION:
Never drop brake pad and caliper assembly.
6. Remove disc rotor. Refer to RAX-7, "
Removal and Installation".
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 spill or splash brake fluid on painted surfaces. Brake fluid may seriously damage paint. Wipe it
off immediately and wash with wate r if it gets on a painted surface.
 Never depress the brake pedal. Brake fluid may splash while removing the brake hose.
 If the brake fluid or grease adheres to the brake calip er assembly and disc rotor, quickly wipe it off.
1. Install disc rotor. Refer to RAX-7, "
Removal and Installation".
2. Install the brake caliper assembly to the axle hous ing and tighten the torque member mounting bolts to the
specified torque.
CAUTION:
Never spill or splash any grease and moisture on the brake caliper assembly mounting face,
threads, mounting bolts. Wipe out any grease and moisture.
3. Install brake hose to brake caliper assembly. Refer to BR-26, "
REAR : Removal and Installation".
4. Perform the air bleeding. Refer to BR-11, "
Bleeding Brake System".
5. Check a drag of rear disc brake. If any drag is found, refer to BR-45, "
BRAKE CALIPER ASSEMBLY :
Inspection".
6. Install tires with power tool. Refer to WT-64, "
Exploded View".
BRAKE CALIPER ASSEMBLY : Disassembly and AssemblyINFOID:0000000006222500
DISASSEMBLY
NOTE:
Never remove the torque member, brake pads and pad retainers when disassembling and assembling the cyl-
inder body.
1. Remove the sliding pin bolt, and remove the cylinder body from the torque member.
CAUTION:
Fix the brake pad at suitable tape so that the brake pad will not drop.
2. Remove sliding pin boots from torque member.
3. Remove bushing from sliding pin bolt.
4. Place a wooden block as shown in the figure, and blow air from brake hose mounting hole to remove piston and piston boot.
CAUTION:
Never get fingers caught in the piston.
MAA0272D
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