2007 INFINITI QX56 brake fluid

REAR DISC BRAKE
BR-27
< SERVICE INFORMATION >
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Make sure there is no wear, damage, or cracks in sliding sleeve and sliding sleeve boots, and if there are,
replace them.
ASSEMBLY
CAUTION:
Do not use NISSAN Rubber Grease (KRE00 00010, KRE00 00010 01) when assembling.
1. Apply clean brake fluid to new piston seal and insert in to
groove on cylinder body. Refer to MA-10
.
CAUTION:
Do not reuse piston seal.
2. Apply brake fluid to piston and to piston boot, then install piston
boot in to piston groove. Refer to MA-10
.
CAUTION:
Do not reuse piston boot.
3. Insert into cylinder body by hand and insert piston boot piston-side lip into piston groove.
CAUTION:
Press piston evenly and vary the pressing point to prevent cylinder body inner wall from being
rubbed.
4. Install sliding boots and sleeves to cylinder body.
DISC ROTOR INSPECTION
Visual Inspection
Check surface of disc rotor for uneven wear, cracks, and serious damage. If any non-standard condition is
detected, replace applicable part.
Runout Inspection
1. Using wheel nuts, install disc rotor to wheel hub. (2 or more positions.)
2. Inspect runout using a dial gauge. [Measured at 10 mm (0.39 in)
inside disk edge.]
NOTE:
Make sure that wheel bearing axial end play is within the specifi-
cation before measuring runout. Refer to RAX-5, "
On-Vehicle
Inspection and Service" .
3. If runout is outside the limit, find the minimum runout point by
shifting mounting positions of disc rotor and wheel hub by one
hole.
4. If runout still out of specification, turn rotor with on-car brake lathe.
Thickness Inspection
WFIA0210E
WFIA0211E
Runout limit (on vehicle) : 0.05 mm (0.002 in)
BRA0013D

SERVICE DATA AND SPECIFICATIONS (SDS)
BR-29
< SERVICE INFORMATION >
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SERVICE DATA AND SPECIFICATIONS (SDS)
General SpecificationINFOID:0000000003532748
Unit: mm (in)
Brake PedalINFOID:0000000003532749
Unit: mm (in)
Front brake Brake model AD41VA
Rotor outer diameter × thickness 350 x 30 (13.78 x 1.18)
Pad Length × width × thickness 151.6 x 56.5 x 12.0 (5.97 x 2.22 x 0.476)
Cylinder bore diameter 51 (2.01)
Rear brake Brake model AD14VE
Rotor outer diameter × thickness 320 x 14 (12.60 x 0.551)
Pad Length × width × thickness 83.0 x 33.0 x 12.13 (3.268 x 1.299 x 0.478)
Cylinder bore diameter 48 (1.89)
Control valve Valve model Electric brake force distribution
Brake booster Booster model C215T
Diaphragm diameter 215 (8.46)
Recommended brake fluid Refer to MA-10
Free height "H"182.3 - 192.3 mm (7.18 - 7.57 in)
Depressed pedal height "D" [under a force of 490 N (50 kg-f, 110 lb-f) with engine
running]More than 90.3 mm (3.55 in)
Clearance between pedal stopper and threaded end of stop lamp switch and
ASCD switch "C
1 " or “C2 ”0.74 - 1.96 mm (0.029 - 0.077 in)
Pedal play "A"3 - 11 mm (0.12 - 0.43 in)
WFIA0160E

BRC-1
BRAKES
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SECTION BRC
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CONTENTS
BRAKE CONTROL SYSTEM
VDC/TCS/ABS
SERVICE INFORMATION ............................
3
PRECAUTIONS ...................................................3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
3
Precaution for Brake System ....................................3
Precaution When Using CONSULT-II .......................3
Precaution for Brake Control .....................................4
Precaution for CAN System ......................................4
PREPARATION ...................................................6
Special Service Tool .................................................6
Commercial Service Tool ..........................................6
SYSTEM DESCRIPTION .....................................7
System Component ...................................................7
ABS Function ............................................................8
EBD Function ............................................................8
TCS Function ............................................................8
VDC Function ............................................................8
Fail-Safe Function .....................................................8
Hydraulic Circuit Diagram .........................................9
CAN COMMUNICATION ....................................10
System Description .................................................10
TROUBLE DIAGNOSIS .....................................11
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ......................................................
11
Component Parts and Harness Connector Loca-
tion ..........................................................................
14
Schematic ...............................................................15
Wiring Diagram - VDC - ..........................................16
Basic Inspection ......................................................22
Warning Lamp and Indicator Timing .......................23
Control Unit Input/Output Signal Standard ..............23
CONSULT-II Function (ABS) ..................................26
TROUBLE DIAGNOSIS FOR SELF-DIAG-
NOSTIC ITEMS .................................................
34
Wheel Sensor System Inspection ............................34
Engine System Inspection .......................................35
ABS/TCS/VDC Control Unit Inspection ...................35
Steering Angle Sensor System ................................36
Yaw Rate/Side/Decel G Sensor System Inspec-
tion ...........................................................................
37
Solenoid and VDC Change-Over Valve System
Inspection ................................................................
38
Actuator Motor, Motor Relay, and Circuit Inspec-
tion ...........................................................................
39
Stop Lamp Switch System Inspection .....................40
ABS/TCS/VDC Control Unit Power and Ground
Systems Inspection .................................................
41
Brake Fluid Level Switch System Inspection ...........42
Active Booster System Inspection ...........................43
Delta Stroke Sensor System Inspection ..................44
Pressure Sensor System Inspection .......................45
Steering Angle Sensor Safe Mode Inspection .........47
CAN Communication System Inspection .................48
ICC System Inspection ............................................48
Inspection for Self-Diagnosis Result "ST ANG
SEN SIGNAL" ..........................................................
48
Inspection for Self-Diagnosis Result "DECEL G
SEN SET" ................................................................
49
TROUBLE DIAGNOSES FOR SYMPTOMS .....50
ABS Works Frequently ............................................50
Unexpected Pedal Action ........................................50
Long Stopping Distance ..........................................51
ABS Does Not Work ................................................51
Pedal Vibration or ABS Operation Noise .................51
Vehicle Jerks During TCS/VDC Activation ..............52
Component Inspection .............................................53
ON-VEHICLE SERVICE ....................................54
Adjustment of Steering Angle Sensor Neutral Po-
sition ........................................................................
54
Calibration of Decel G Sensor .................................54

PRECAUTIONS
BRC-3
< SERVICE INFORMATION >[VDC/TCS/ABS]
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SERVICE INFORMATION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000003532761
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity 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 and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal
injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag
Module, see the SRS section.
• Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or har-
ness connectors.
Precaution for Brake SystemINFOID:0000000003532762
CAUTION:
• Refer to MA-10
for recommended brake fluid.
• Never reuse drained brake fluid.
• Be careful not to splash brake fluid on painted areas; it may cause paint damage. If brake fluid is
splashed on painted areas, wash it away with water immediately.
• To clean or wash all parts of master cylinder and disc brake caliper, use clean brake fluid.
• Never use mineral oils such as gasoline or kerosene. They will ruin rubber parts of the hydraulic sys-
tem.
• Use flare nut wrench when removing and installing brake
tube.
• If a brake fluid leak is found, the part must be disassembled
without fail. Then it has to be replaced with a new one if a
defect exists.
• Turn the ignition switch OFF and remove the connector of the
ABS actuator and electric unit (control unit) or the battery ter-
minal before performing the work.
• Always torque brake lines when installing.
• Burnish the brake contact surfaces after refinishing or replac-
ing rotors, after replacing pads, or if a soft pedal occurs at
very low mileage.
Refer to BR-20, "
Disassembly and Assembly of Brake Caliper" (front disc brake) or BR-26, "Brake
Caliper" (rear disc brake).
WARNING:
• Clean brake pads and shoes with a waste cloth, then wipe with a dust collector.
Precaution When Using CONSULT-IIINFOID:0000000003532763
When connecting CONSULT-II to data link connector, connect them through CONSULT-II CONVERTER.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
CHECK POINTS FOR USING CONSULT-II
1. Has CONSULT-II been used without connecting CONSULT-II CONVERTER on this vehicle?
SBR686C

BRC-4
< SERVICE INFORMATION >[VDC/TCS/ABS]
PRECAUTIONS
• If YES, GO TO 2.
• If NO, GO TO 5.
2. Is there any indication other than indications relating to CAN communication system in the self-diagnosis
results?
• If YES, GO TO 3.
• If NO, GO TO 4.
3. Based on self-diagnosis results unrelated to CAN communication, carry out the inspection.
4. Malfunctions may be detected in self-diagnosis depending on control units carrying out CAN communica-
tion. Therefor, erase the self-diagnosis results.
5. Diagnose CAN communication system. Refer to LAN-7
.
Precaution for Brake ControlINFOID:0000000003532764
• During ABS operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.
• Just after starting vehicle, the brake pedal may vibrate or a motor operating noise may be heard from engine
compartment. This is a normal status of operation check.
• Stopping distance may be longer than that of vehicles without ABS when vehicle drives on rough, gravel, or
snow-covered (fresh, deep snow) roads.
• When an error is indicated by ABS or another warning lamp, collect all necessary information from customer
(what symptoms are present under what conditions) and check for simple causes before starting diagnosis.
Besides electrical system inspection, check booster operation, brake fluid level, and fluid leaks.
• If incorrect tire sizes or types are installed on the vehicle or brake pads are not Genuine NISSAN parts, stop-
ping distance or steering stability may deteriorate.
• If there is a radio, antenna or related wiring near control module, ABS function may have a malfunction or
error.
• If aftermarket parts (car stereo, CD player, etc.) have been installed, check for incidents such as harness
pinches, open circuits or improper wiring.
• If the following components are replaced with non-genuine components or modified, the VDC OFF indicator
lamp and SLIP indicator lamp may turn on or the VDC system may not operate properly. Components
related to suspension (shock absorbers, struts, springs, bushings, etc.), tires, wheels (exclude specified
size), components related to brake system (pads, rotors, calipers, etc.), components related to engine (muf-
fler, ECM, etc.), components related to body reinforcement (roll bar, tower bar, etc.).
• Driving with broken or excessively worn suspension components, tires or brake system components may
cause the VDC OFF indicator lamp and the SLIP indicator lamp to turn on, and the VDC system may not
operate properly.
• When the TCS or VDC is activated by sudden acceleration or sudden turn, some noise may occur. The
noise is a result of the normal operation of the TCS and VDC.
• When driving on roads which have extreme slopes (such as mountainous roads) or high banks (such as
sharp curves on a freeway), the VDC may not operate normally, or the VDC warning lamp and the SLIP indi-
cator lamp may turn on. This is not a problem if normal operation can be resumed after restarting the engine.
• Sudden turns (such as spin turns, acceleration turns), drifting, etc. with VDC turned off may cause the yaw
rate/side/decel G sensor to indicate a problem. This is not a problem if normal operation can be resumed
after restarting the engine.
Precaution for CAN SystemINFOID:0000000003532765
• Do not apply voltage of 7.0V or higher to terminal to be measured.
• Maximum open terminal voltage of tester in use must be less than 7.0V.
• Before checking harnesses, turn ignition switch OFF and disconnect battery negative cable.

BRC-8
< SERVICE INFORMATION >[VDC/TCS/ABS]
SYSTEM DESCRIPTION
ABS Function
INFOID:0000000003532769
• The Anti-Lock Brake System detects wheel revolution while braking and improves handling stability during
sudden braking by electrically preventing wheel lockup. Maneuverability is also improved for avoiding obsta-
cles.
• If the electrical system malfunctions, the Fail-Safe function is activated, the ABS becomes inoperative and
the ABS warning lamp turns on.
• The electrical system can be diagnosed using CONSULT-II.
• During ABS operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.
• Just after starting the vehicle, the brake pedal may vibrate or a motor operating noise may be heard from
engine compartment. This is a normal status of operation check.
• Stopping distance may be longer than that of vehicles without ABS when vehicle drives on rough, gravel, or
snow-covered (fresh, deep snow) roads.
EBD FunctionINFOID:0000000003532770
• Electronic Brake Distribution is a function that detects subtle slippages between the front and rear wheels
during braking, and it improves handling stability by electronically controlling the brake fluid pressure which
results in reduced rear wheel slippage.
• If the electrical system malfunctions, the Fail-Safe function is activated, the EBD and ABS become inopera-
tive, and the ABS warning lamp and BRAKE warning lamp are turned on.
• The electrical system can be diagnosed using CONSULT-II.
• During EBD operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.
• Just after starting the vehicle, the brake pedal may vibrate or a motor operating noise may be heard from
engine compartment. This is a normal status of operation check.
TCS FunctionINFOID:0000000003532771
• Spinning of the drive wheels is detected by the ABS actuator and electric unit (control unit) using inputs from
the wheel speed sensors. If wheel spin occurs, the drive wheel right and left brake fluid pressure control and
engine fuel cut are activated while the throttle value is restricted to reduce the engine torque and decrease
the amount of wheel spin. In addition, the throttle opening is controlled to achieve the optimum engine
torque.
• Depending on road condition, the vehicle may have a sluggish feel. This is normal, because optimum trac-
tion has the highest priority during TCS operation.
• TCS may be activated during sudden vehicle acceleration, wide open throttle acceleration, sudden transmis-
sion shifts or when the vehicle is driven on a road with a varying surface friction coefficient.
• The SLIP indicator lamp flashes to inform the driver of TCS operation.
VDC FunctionINFOID:0000000003532772
• In addition to the ABS/TCS function, the driver steering amount and brake operation amount are detected
from the steering angle sensor and front and rear pressure sensors, and the vehicle's driving status (amount
of under steering/over steering) is determined using inputs from the yaw rate sensor/side G sensor, wheel
speed sensors, etc. and this information is used to improve vehicle stability by controlling the braking and
engine torque application to the wheels.
• The SLIP indicator lamp flashes to inform the driver of VDC operation.
• During VDC operation, the vehicle body and brake pedal may vibrate lightly and a mechanical noise may be
heard. This is normal.
• The ABS warning lamp, VDC OFF indicator lamp and SLIP indicator lamp may turn on when the vehicle is
subject to strong shaking or large vibration, such as when the vehicle is on a turn table or a ship while the
engine is running or on a steep slope. In this case, restart the engine on a normal road and if the ABS warn-
ing lamp, VDC OFF indicator lamp and SLIP indicator lamp turn off, there is no problem.
Fail-Safe FunctionINFOID:0000000003532773
CAUTION:
If the Fail-Safe function is activated, perform the Self Diagnosis for ABS/TCS/VDC system.
ABS/EBD SYSTEM

TROUBLE DIAGNOSIS
BRC-11
< SERVICE INFORMATION >[VDC/TCS/ABS]
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TROUBLE DIAGNOSIS
How to Perform Trouble Diagnosis for Quick and Accurate RepairINFOID:0000000003532776
INTRODUCTION
The ABS/TCS/VDC system has an electronic control unit to control
major functions. The control unit accepts input signals from sensors
and controls actuator operation. It is also important to check for con-
ventional malfunctions such as air leaks in the booster or lines, lack
of brake fluid, or other malfunctions with the brake system.
It is much more difficult to diagnose a malfunction that occurs inter-
mittently rather than continuously. Most intermittent malfunctions are
caused by poor electrical connections or wiring. In this case, careful
checking of suspicious circuits may help prevent the replacement of
good parts.
A visual check only may not find the cause of the malfunction, so a
road test should be performed.
Before undertaking actual checks, take just a few minutes to talk with
a customer who approaches with an ABS/TCS/VDC complaint. The
customer is a very good source of information, especially for inter-
mittent malfunctions. Through the talks with the customer, find out
what symptoms are present and under what conditions they occur.
Start your diagnosis by looking for “conventional” malfunctions first.
This is one of the best ways to troubleshoot brake malfunctions on
an ABS/TCS/VDC equipped vehicle. Also check related Service Bul-
letins for information.
SEF233G
SEF234G

BRC-22
< SERVICE INFORMATION >[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
Basic Inspection
INFOID:0000000003532780
BRAKE FLUID LEVEL, FLUID LEAK, AND BRAKE PAD INSPECTION
1. Check fluid level in the brake fluid reservoir. If fluid level is low, add fluid.
2. Check the brake piping and around the ABS actuator and electric unit (control unit) for leaks. If there is
leaking or seeping fluid, check the following items.
• If ABS actuator and electric unit (control unit) connection is loose, tighten the piping to the specified
torque and recheck for leaks.
WFWA0320E