Ins INFINITI QX56 2004 Factory Service Manual

BR-1
BRAKE SYSTEM
F BRAKES
CONTENTS
C
D
E
G
H
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J
K
L
M
SECTION BR
A
B
BR
Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions for Brake System .................................. 3
PREPARATION ........................................................... 4
Special Service Tool ................................................. 4
Commercial Service Tools ........................................ 4
NOISE, VIBRATION, AND HARSHNESS (NVH)
TROUBLESHOOTING ................................................ 5
NVH Troubleshooting Chart ..................................... 5
BRAKE PEDAL .......................................................... 6
Inspection and Adjustment ....................................... 6
INSPECTION ........................................................ 6
ADJUSTMENT ...................................................... 7
Removal and Installation .......................................... 8
REMOVAL ............................................................. 8
INSPECTION AFTER REMOVAL ......................... 9
INSTALLATION ..................................................... 9
BRAKE FLUID .......................................................... 10
On-board Inspection ............................................... 10
LEVEL CHECK ................................................... 10
Drain and Refill ....................................................... 10
Bleeding Brake System ...........................................11
BRAKE PIPING AND HOSE .................................... 12
Hydraulic Circuit ..................................................... 12
Removal and Installation of Front Brake Hose ....... 12
REMOVAL ........................................................... 12
INSTALLATION ................................................... 13
Removal and Installation of Rear Brake Hose ....... 13
REMOVAL ........................................................... 13
INSTALLATION ................................................... 13
Inspection After Installation .................................... 14
BRAKE MASTER CYLINDER .................................. 15
On-board Inspection ............................................... 15
LEAK INSPECTION ............................................ 15
Removal and Installation ........................................ 15
REMOVAL ........................................................... 15INSTALLATION ................................................... 16
Disassembly and Assembly .................................... 16
DISASSEMBLY ................................................... 16
ASSEMBLY ......................................................... 16
BRAKE BOOSTER ................................................... 17
On-Vehicle Service ................................................. 17
OPERATING CHECK .......................................... 17
AIRTIGHT CHECK .............................................. 17
Removal and Installation ........................................ 18
REMOVAL ........................................................... 18
INSPECTION AFTER REMOVAL ....................... 18
INSTALLATION ................................................... 19
VACUUM LINES ....................................................... 20
Removal and Installation ........................................ 20
Inspection ............................................................... 20
VISUAL INSPECTION ......................................... 20
CHECK VALVE INSPECTION ............................. 20
FRONT DISC BRAKE ............................................... 21
On-vehicle Inspection ............................................. 21
PAD WEAR INSPECTION ................................... 21
Components ........................................................... 21
Removal and Installation of Brake Pad .................. 22
REMOVAL ........................................................... 22
INSTALLATION ................................................... 22
Removal and Installation of Brake Caliper and Disc
Rotor ....................................................................... 22
REMOVAL ........................................................... 22
INSTALLATION ................................................... 23
Disassembly and Assembly of Brake Caliper
Assembly ................................................................ 23
DISASSEMBLY ................................................... 23
CALIPER INSPECTION ...................................... 24
ASSEMBLY ......................................................... 24
DISC ROTOR INSPECTION ............................... 25
BRAKE BURNISHING PROCEDURE ................. 25
REAR DISC BRAKE ................................................. 27
On-vehicle Inspection ............................................. 27
PAD WEAR INSPECTION ................................... 27
Components ........................................................... 27
Removal and Installation of Brake Pad .................. 28

BR-2Revision: August 20072004 QX56 REMOVAL ........................................................... 28
INSTALLATION .................................................... 28
Removal and Installation of Brake Caliper Assembly
and Disc Rotor ........................................................ 28
REMOVAL ........................................................... 28
INSTALLATION .................................................... 28
Disassembly and Assembly of Brake Caliper
Assembly ................................................................ 29
DISASSEMBLY ................................................... 29
CALIPER INSPECTION ...................................... 29
ASSEMBLY ......................................................... 30
DISC ROTOR INSPECTION ............................... 30
BRAKE BURNISHING PROCEDURE ................. 31SERVICE DATA AND SPECIFICATIONS (SDS) ......32
General Specifications ............................................32
Brake Pedal ............................................................32
Brake Booster .........................................................32
Check Valve ............................................................32
Front Disc Brake .....................................................32
Rear Disc Brake ......................................................33

PRECAUTIONS
BR-3
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MA
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BR
Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EFS003P3
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.
WA RN ING:

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 per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal 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
harness connectors.
Precautions for Brake SystemEFS0062U

Refer to MA-10, "RECOMMENDED FLUIDS AND LUBRICANTS" for recommended brake fluid.

Do not reuse drained brake fluid.

Be careful not to splash brake fluid on painted areas.

To clean or wash all parts of master cylinder, disc brake caliper and wheel cylinder, use clean brake fluid.

Do not use mineral oils such as gasoline or kerosene. They will ruin rubber parts of the hydraulic system.

Use flare nut wrench when removing and installing brake tube.

Always check tightening torque when installing brake lines.

Before working, turn ignition switch to OFF and disconnect con-
nectors for ABS actuator and electric unit (control unit) or battery
terminals.

Burnish the brake contact surfaces after refinishing or replacing
drums or rotors, after replacing pads or linings, or if a soft pedal
occurs at very low mileage. Refer to BR-25, "
BRAKE BURNISH-
ING PROCEDURE" .
WA RN ING:

Clean brake pads and shoes with a waste cloth, then wipe
with a dust collector.SBR6 86 C

BR-4
PREPARATION
Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolEFS0062T
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Commercial Service ToolsEFS003P5
Tool number
(Kent-Moore No.)
Tool nameDescription
—
(J-46532)
Brake and clutch pedal height measure-
ment toolMeasuring brake pedal height.
LFIA0227E
Tool nameDescription
1. Flare nut crowfoot
2. Torque wrenchRemoving and installing brake piping.
a: 10 mm (0.39 in) / 12 mm (0.47 in)
Power toolRemoving bolts, nuts, and screws.
S-NT360
PBIC0190E
PBIC0191E

BR-6
BRAKE PEDAL
Revision: August 20072004 QX56
BRAKE PEDALPFP:46501
Inspection and Adjustment EFS003P7
INSPECTION
1. Inspect the brake pedal free height "H" from the lower dash panel using tool.
2. Adjust the height referring to the following specifications.
CAUTION:
The adjustable pedal must be in the forwardmost (closest to
the floor) position for pedal height measurement.
Brake Pedal SpecificationsTool number : — (J-46532)
WFIA0160E
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, 110 lb) 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": 0.74 - 1.96 mm (0.029 - 0.077 in)
Pedal play "A" : 3 - 11 mm (0.12 - 0.43 in)

BRAKE PEDAL
BR-7
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BR
Revision: August 20072004 QX56
ADJUSTMENT
1. Loosen the stop lamp switch and ASCD switch by turning 45° counterclockwise.
2. Loosen lock nut on the input rod, then turn input rod to adjust the
pedal to specified height. When finished adjusting, tighten lock
nut.
CAUTION:
Make sure that the screw portion of the end of input rod is
located inside the clevis.
3. With the pedal pulled up and held by hand, press the stop lamp
switch and the ASCD switch in until threaded ends contact pedal
arm.
4. With the threaded ends of the stop lamp switch and ASCD
switch contacting the pedal arm, turn the switches 45° clockwise
to lock in place.
CAUTION:
Make sure that the gap (C) between the rubber stops and
switch ends are within specification.
5. Check the pedal play.
CAUTION:
Make sure that the stop lamp goes off when the pedal is
released.
6. Start the engine and check the height of the brake pedal when
depressing it.Lock nut : 18.5 N·m (1.9 kg-m, 14 ft-lb)
PFIA0436E

BR-8
BRAKE PEDAL
Revision: August 20072004 QX56
Removal and Installation EFS003P8
REMOVAL
WAR NIN G:
Do not deform the brake tube.
CAUTION:

Before removal and installation the accelerator and brake pedals must be in the forward most
position (closest to the floor). This is to align the base position of the accelerator and brake ped-
als.

Do not disassemble the brake pedal adjusting mechanism.

Avoid damage from dropping the brake pedal assembly during handling.

Keep the brake pedal assembly away from water.
1. Remove the lower driver instrument panel. Refer to IP-13, "
Instrument Lower Cover LH" .
2. Remove the stop lamp switch and ASCD switch from the pedal assembly.
1. Brake pedal assembly 2. Snap pin 3. Clip
4. Stop lamp switch 5. Pedal pad 6. Clevis pin
7. ASCD cancel switch
WFIA0232E

BRAKE PEDAL
BR-9
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BR
Revision: August 20072004 QX56
3. Disconnect the adjustable brake pedal cable from the adjustable
pedal electric motor.

Unlock (1) then pull (2) the adjustable brake pedal cable to
disconnect it from the adjustable pedal electric motor as
shown.
4. Remove snap pin and clevis pin from the clevis of brake booster.
5. Remove mounting nuts and the pedal assembly.

Temporarily install nuts by hand to support booster.
CAUTION:

Before removal and installation the accelerator and brake
pedals must be in the forwardmost position (closest to
the floor). This is to align the base position of the accelerator and brake pedals.

Do not disassemble the brake pedal adjusting mechanism.

Avoid damage from dropping the brake pedal assembly during handling.

Keep the brake pedal assembly away from water.
INSPECTION AFTER REMOVAL
Check brake pedal for following items.

Crack or deformation of clevis pin stopper

Clevis pin deformation

Crack of any welded portion

Brake pedal bend
INSTALLATION
1. Installation is in the reverse order of removal.

Check the brake pedal for smooth operation. There should be no binding or sticking when applying or
releasing the brake pedal.

Check the brake pedal adjustable feature for smooth operation. There should be no binding or sticking
when adjusting the brake pedal forward or backward.

After installing the brake pedal assembly in the vehicle, be sure to adjust it. Refer to BR-6, "Inspection and
Adjustment" .
LBIA0374E
SBR9 97

BR-10
BRAKE FLUID
Revision: August 20072004 QX56
BRAKE FLUIDPFP:KN100
On-board InspectionEFS003P9
LEVEL CHECK

Make sure the fluid level in reservoir tank is within the standard
(between MAX and MIN lines).

Visually check around reservoir tank for fluid leaks.

If fluid level is excessively low, check brake system for leaks.

If brake warning lamp remains illuminated after parking lever is
released, check brake system for fluid leakage.
Drain and RefillEFS003PA
CAUTION:

Refill with recommended brake fluid. Refer to MA-10, "RECOMMENDED FLUIDS AND LUBRI-
CANTS" .

Do not reuse drained brake fluid.

Do not let brake fluid splash on the painted surfaces of the body. This might damage the paint, so
when splashing it, immediately wipe off the area and wash away with water.

Before servicing, disconnect actuator connector or battery negative cable.
1. Connect a vinyl tube to each bleed valve.
2. Depress brake pedal, loosen each bleed valve, and gradually
remove brake fluid.
3. Make sure there is no foreign material in reservoir tank, and refill
with new brake fluid.
4. Rest foot on brake pedal. Loosen bleed valve. Slowly depress
pedal until it stops. Tighten bleed valve. Release brake pedal.
Repeat this process a few times, then pause to add new brake
fluid to master cylinder. Continue until new brake fluid flows out.
Bleed air from brake system. Refer to BR-11, "
Bleeding Brake
System" .
LFIA0225E
SBR4 19 C
SBR9 95

BR-12
BRAKE PIPING AND HOSE
Revision: August 20072004 QX56
BRAKE PIPING AND HOSEPFP:46210
Hydraulic CircuitEFS003PC
CAUTION:

All hoses and tubes must be free from excessive bending, twisting and pulling.

Make sure there is no interference with other parts when turning steering both clockwise and
counterclockwise.

The brake piping is an important safety part. If a brake fluid leak is detected, always disassemble
the parts. Replace applicable part with a new one, if necessary.

Be careful not to splash brake fluid on painted areas; it way cause paint damage. If brake fluid is
splashed on painted areas, wash it away with water immediately.

Do not bend or twist brake hose sharply, or strongly pull it.

When removing components, cover connections so that no dirt, dust, or other foreign matter gets
in.

Refill with recommended brake fluid. Refer to MA-10, "RECOMMENDED FLUIDS AND LUBRI-
CANTS" .

Do not reuse drained brake fluid.
Removal and Installation of Front Brake Hose EFS003PD
REMOVAL
1. Drain brake fluid. Refer to BR-10, "Drain and Refill" .
2. Using a flare nut wrench, remove brake tube from brake hose.
3. Remove lock plate and brake hose from bracket.
4. Remove union bolt and then remove brake hose from caliper assembly.
1. Actuator 2. Master cylinder 3. Brake booster
4. Connector
WFIA0278E