2007 INFINITI QX56 service

BR-10
< SERVICE INFORMATION >
BRAKE PIPING AND HOSE
BRAKE PIPING AND HOSE
Hydraulic CircuitINFOID:0000000003532727
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 coun-
terclockwise.
• 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 new brake fluid. Refer to MA-10
.
• Do not reuse drained brake fluid.
Removal and Installation of Front Brake HoseINFOID:0000000003532728
REMOVAL
1. Drain brake fluid. Refer to BR-8, "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 cylinder body.
INSTALLATION
1. Actuator 2. Master cylinder 3. Brake booster
4. Connector
WFIA0278E

BRAKE PIPING AND HOSE
BR-11
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1. Install brake hose by aligning with the protrusion on cylinder
body, and tighten union bolt. Refer to BR-10, "
Hydraulic Circuit".
CAUTION:
Do not reuse copper washer.
2. Insert brake hose end through bracket, then secure it to bracket
with lock plate.
3. Install brake tube to brake hose, then tighten flare nut using a
flare nut wrench.
4. Refill brake fluid and bleed air. Refer to BR-8, "
Bleeding Brake
System" .
Removal and Installation of Rear Brake HoseINFOID:0000000003532729
REMOVAL
1. Drain brake fluid. Refer to BR-8, "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 cylinder body.
INSTALLATION
1. Install brake hose by aligning with the protrusion on cylinder
body, and tighten union bolt. Refer to BR-10, "
Hydraulic Circuit".
CAUTION:
Do not reuse copper washers.
2. Insert brake hose end through bracket, then secure it to bracket
with lock plate.
3. Install brake tube to brake hose, then tighten flare nut to using a
flare nut wrench. Refer to BR-10, "
Hydraulic Circuit" .
4. Refill brake fluid and bleed air. Refer to BR-8, "
Bleeding Brake
System" .
LFIA0214E
LFIA0213E
LFIA0212E
LFIA0213E

BR-12
< SERVICE INFORMATION >
BRAKE PIPING AND HOSE
Inspection After Installation
INFOID:0000000003532730
CAUTION:
If a leak is detected at the connections, retighten it or, if necessary, replace the damaged part.
1. Check brake tubes and hose connections for fluid leaks, damage, twist, deformation, contact with other
parts, and loose connections. Replace any damage parts.
2. While depressing brake pedal under a force of 785 N (80 kg-f, 177 lb-f) with engine running for approxi-
mately 5 seconds, check for fluid leakage from each part.

BRAKE MASTER CYLINDER
BR-13
< SERVICE INFORMATION >
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BRAKE MASTER CYLINDER
On Board InspectionINFOID:0000000003532731
LEAK INSPECTION
• Check for leaks at brake master cylinder to brake booster attachment point, reservoir tank, and brake tube
connections.
Removal and InstallationINFOID:0000000003532732
REMOVAL
CAUTION:
• 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.
• Before removing brake brake master cylinder, depress the brake pedal 5-6 times with the key OFF to
deplete vacuum in the booster.
1. Drain brake fluid. Refer to BR-8, "
Drain and Refill" .
2. Disconnect harness connectors for fluid level sensor and pressure sensors.
3. Using a flare nut wrench, disconnect brake tube from brake master cylinder.
4. Remove brake master cylinder mounting nuts, and master cylinder assembly.
INSTALLATION
• Installation is in the reverse order of removal.
1. Reservoir cap 2. Fluid level sensor 3. Grommet
4. Master cylinder sub-assembly 5. Front pressure sensor 6. Rear pressure sensor
7. Seal 8. Reservoir tank B. Brake fluid
R. Rubber grease
WFIA0450E

BR-14
< SERVICE INFORMATION >
BRAKE MASTER CYLINDER
• Refill brake fluid and bleed air. Refer to BR-8, "Bleeding Brake System".
CAUTION:
• Refill with new brake fluid. Refer to MA-10
.
• Do not reuse drained brake fluid.
• Adjust brake pedal. Refer to BR-5, "
Inspection and Adjustment" .
Disassembly and AssemblyINFOID:0000000003532733
DISASSEMBLY
CAUTION:
• Master cylinder cannot be disassembled.
• Remove reservoir tank only when absolutely necessary.
Pull reservoir tank off master cylinder sub-assembly, then remove grommets from master cylinder sub-assem-
bly body.
ASSEMBLY
CAUTION:
• Never use mineral oil such as kerosene, gasoline during the cleaning and assembly process.
• Do not drop parts. If a part is dropped, do not use it.
1. Apply brake fluid or rubber grease to new grommets, then insert into master cylinder sub-assembly. Refer
to GI-45
.
CAUTION:
Do not reuse grommet.
2. Install reservoir tank onto master cylinder sub-assembly.

BRAKE BOOSTER
BR-15
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BRAKE BOOSTER
On-Vehicle ServiceINFOID:0000000003532734
OPERATING CHECK
With engine stopped, change the vacuum to the atmospheric pres-
sure by depressing brake pedal several times. Then with brake
pedal fully depressed, start engine and when the vacuum pressure
reaches the standard, make sure the clearance between brake pedal
and floor panel decreases.
CAUTION:
Depressing pedal interval is approximately 5 seconds.
AIRTIGHT CHECK
• Run engine at idle for approximately 1 minute, and stop it after
applying vacuum to booster. Depress brake pedal normally to
change the vacuum to the atmospheric pressure. Make sure dis-
tance between brake pedal and floor panel gradually increases.
• Depress brake pedal while engine is running and stop engine with
pedal depressed. The pedal stroke should not change after holding
pedal down for 30 seconds.
CAUTION:
Depressing pedal interval is approximately 5 seconds.
Removal and InstallationINFOID:0000000003532735
REMOVAL
CAUTION:
• Be careful not to deform or bend brake piping while removing and installing brake booster.
• Replace clevis pin if it is damaged.
BRA0037D
SBR365AA
1. Reservoir tank 2. Brake master cylinder 3. Gasket
4. Brake pedal 5. Lock nut 6. Spacer block
7. Brake booster 8. Active booster 9. Delta stroke sensor
WFIA0381E

BR-16
< SERVICE INFORMATION >
BRAKE BOOSTER
• Be careful not to damage brake booster stud bolt threads. If brake booster is tilted or inclined during
installation, dash panel may damage the threads.
• Attach the check valve in the correct direction.
1. Remove engine room cover with power tool. Refer to EM-12, "
Removal and Installation" .
2. Remove engine air duct assembly. Refer to EM-15, "
Removal and Installation" .
3. Remove brake piping from brake master cylinder.
4. Remove brake master cylinder. Refer to BR-13, "
Removal and Installation" .
5. Remove vacuum hose from brake booster. Refer to BR-17
.
6. Disconnect active boost and delta stroke sensor harness connectors from brake booster assembly.
7. Remove brake pedal attachment snap pin and clevis pin from inside the vehicle.
8. Remove nuts on brake booster and brake pedal assembly.
9. Remove brake booster assembly from dash panel.
INSPECTION AFTER REMOVAL
Output Rod Length Inspection
1. Using a handy vacuum pump, apply a vacuum of – 66.7 kPa (–
500 mmHg, –19.69 inHg) to brake booster.
2. Check output rod length.
INSTALLATION
1. Loosen lock nut to adjust input rod length so that the length B (in
the figure) satisfies the specified value.
2. After adjusting “B”, temporarily tighten lock nut and install
booster assembly to the vehicle.
• Install a gaskets and spacer block between booster assembly
and the dash panel.
3. Connect brake pedal with clevis of input rod.
4. Install pedal bracket mounting nuts and tighten them to the
specified torque.
5. Install brake piping from brake master cylinder to ABS actuator. Refer to BR-10, "
Hydraulic Circuit".
6. Connect active boost and delta stroke sensor harness connectors to brake booster assembly.
7. Connect vacuum hose to brake booster.
8. Install master cylinder to booster assembly. Refer to BR-13, "
Removal and Installation" .
9. Adjust the height and play of brake pedal.
10. Tighten lock nut of input rod to specification.
11. Install engine air duct assembly. Refer to EM-15, "
Removal and Installation" .
12. Install engine room cover with power tool. Refer to EM-12, "
Removal and Installation" .
13. Refill with new brake fluid and bleed air. Refer to BR-8, "
Bleeding Brake System" .
SBR208E
Standard dimension : 15.6 − 15.9 mm (0.614 − 0.626 in)
[when vacuum is – 66.7 kPa (– 500 mmHg, – 19.69 inHg)]
Length “B” : 151 mm (5.94 in)
WFIA0382E

VACUUM LINES
BR-17
< SERVICE INFORMATION >
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VACUUM LINES
Removal and InstallationINFOID:0000000003532736
1. Disconnect vacuum hose from hose clip.
2. Release clamps and disconnect vacuum hose.
3. Remove check valve from brake booster.
4. Installation is in the reverse order of removal.
CAUTION:
• Insert vacuum hose for at least 24 mm (0.94 in).
• Do not use lubricating oil during assembly.
InspectionINFOID:0000000003532737
VISUAL INSPECTION
Check for improper assembly, damage and deterioration.
CHECK VALVE INSPECTION
Airtightness Inspection
Use a suitable vacuum pump to check. Connect to brake booster
side of check valve.
1. Hose clip 2. Clamp 3. Vacuum hose
4. Check valve
LFIA0216E
SBR225B
Check
valve
specifi-
cation: Vacuum decrease should be within 1.3 kPa
(10 mmHg, 0.39 inHg) for 15 seconds under
a vacuum of – 66.7 kPa (– 500 mmHg, – 19.69
inHg)
LFIA0217E