2008 INFINITI QX56 air bleeding

BR-1
BRAKES
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CONTENTS
BRAKE SYSTEM
PRECAUTION ....... ........................................3
PRECAUTIONS .............................................. .....3
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
3
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
3
Precaution for Brake System ....................................4
PREPARATION ............................................5
PREPARATION .............................................. .....5
Special Service Tool ........................................... ......5
Commercial Service Tool ..........................................5
FUNCTION DIAGNOSIS ...............................6
NOISE, VIBRATION AND HARSHNESS
(NVH) TROUBLESHOOTING ........................ .....
6
NVH Troubleshooting Chart ................................ ......6
BASIC INSPECTION ....................................7
FRONT DISC B RAKE .................................... .....7
BRAKE PAD .......................................................... ......7
BRAKE PAD : Inspection ..........................................7
DISC ROTOR ......................................................... ......7
DISC ROTOR : Inspection ........................................7
REAR DISC BRAKE ...................................... .....9
BRAKE PAD .......................................................... ......9
BRAKE PAD : Inspection ..........................................9
DISC ROTOR ......................................................... ......9
DISC ROTOR : Inspection ........................................9
BRAKE BOOSTER ............................................10
Inspection ............................................................ ....10
VACUUM LINES ............................................. ....11
Inspection ............................................................ ....11
BRAKE MASTER CYLINDER ..........................12
On Board Inspection ................................................12
BRAKE TUBE AND HOSE ...............................13
Hydraulic Circuit ......................................................13
FRONT BRAKE ..................................................... ....13
FRONT BRAKE : Inspection ......................... ...........13
REAR BRAKE ........................................................ ....14
REAR BRAKE : Inspection ........................ ..............14
ON-VEHICLE MAINTEN ANCE ....................15
BRAKE PEDAL .................................................15
Inspection and Adjustment .................................. ....15
BRAKE FLUID ..................................................17
On Board Inspection ............................................ ....17
Drain and Refill ........................................................17
Bleeding Brake System ...........................................17
ON-VEHICLE REPAIR .................................19
BRAKE PEDAL .................................................19
Removal and Installation ..................................... ....19
BRAKE TUBE AND HOSE ...............................21
Hydraulic Circuit ......................................................21
Removal and Installation of Front Brake Piping
and Brake Hose .......................................................
21
Removal and Installation of Rear Brake Piping
and Brake Hose .......................................................
22
Inspection After Installation .....................................23
BRAKE MASTER CYLINDER ..........................25
Removal and Installation .........................................25
BRAKE BOOSTER ...........................................26
Removal and Installation ..................................... ....26
VACUUM LINES ...............................................28
Revision: March 2010 2008 QX56

BRAKE FLUIDBR-17
< ON-VEHICLE MAINTENANCE >
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BRAKE FLUID
On Board InspectionINFOID:0000000004894493
LEVEL CHECK
• Make sure the fluid level in reservoir tank is between MAX and MIN lines as shown.
• 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 brake pedal is released, check brake system for fluid leaks.
Drain and RefillINFOID:0000000004894494
CAUTION:
• Refill with new brake fluid. Refer to MA-12, "
Fluids and Lubricants".
• 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 if
splashing it, immediately wipe off the area and wash away with water.
• Before servicing, disconnect ABS actuator and electri c unit (control unit) connector or battery nega-
tive terminal.
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
of the bleed valve.
Bleed the air out of the brake hydraulic system. Refer to BR-17,
"Bleeding Brake System".
Bleeding Brake SystemINFOID:0000000004894495
CAUTION:
While bleeding, pay attention to master cylinder fluid level.
1. Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector or battery
negative terminal.
2. Connect a vinyl tube to the rear right bleed valve.
LFIA0225E
SBR419C
SBR995
Revision: March 2010 2008 QX56

BRAKE TUBE AND HOSEBR-23
< ON-VEHICLE REPAIR >
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3. Remove brake tube from brake hose, using a suitable tool.
4. Remove lock plate and brake hose from bracket.
5. Remove union bolt and then remove brake hose from cylinder body.
INSTALLATION
1. Install brake hose by aligning with the protrusion on cylinderbody, then install the union bolt and new copper washers and
tighten to specification. Refer to BR-13, "
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 the flare nut using a suitable tool. Refer to BR-13, "
Hydraulic Circuit".
4. Refill brake fluid and bleed air. Refer to BR-17, "
Bleeding Brake System".
5. Install rear wheel and tire. Refer to WT-48, "
Rotation".
Inspection After InstallationINFOID:0000000004894509
CAUTION:
Brake tubes and hoses are important safety parts. Always disassemble the parts and retighten their fit-
tings, if a brake fluid leak is detected. Replace applicable part with a new one, if a damaged part is
detected.
LFIA0213E
LFIA0212E
SFIA1137E
LFIA0213E
Revision: March 2010 2008 QX56

BRAKE MASTER CYLINDERBR-25
< ON-VEHICLE REPAIR >
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BRAKE MASTER CYLINDER
Removal and InstallationINFOID:0000000004894510
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 master cylinder, depress the brake pedal 5-6 times with the key OFF to deplete vacuum in the booster.
1. Remove brake reservoir cap.
2. Disconnect harness connectors for fluid level sensor, front and rear pressure sensors.
3. Using suitable tool, disconnect brake tube from master cylinder assembly.
4. Remove master cylinder assembly nuts, and remove master cylinder assembly.
INSTALLATION
Installation is in the reverse order of removal.
• Refill brake fluid and bleed air. Refer to BR-17, "
Bleeding Brake System".
CAUTION:
• Refill with new brake fluid. Refer to MA-12, "
Fluids and Lubricants".
• Do not reuse drained brake fluid.
• Adjust brake pedal. Refer to BR-15, "
Inspection and Adjustment".
1. Reservoir cap 2. Fluid level sensor 3. Grommet
4. Master cylinder assembly 5. Rear pressure sensor6. Front pressure sensor
7. Seal 8. Reservoir tankB. Brake fluid
R. Rubber grease
AWFIA0415GB
Revision: March 2010 2008 QX56

BRAKE BOOSTERBR-27
< ON-VEHICLE REPAIR >
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1. Using a hand 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 r od length so that the length (B)
is set at the specified value.
2. After adjusting length (B), temporarily tighten lock nut and install brake booster and spacer block.
• Install the gaskets and spacer block between brake boosterand dash panel.
3. Connect brake pedal to clevis on the input rod.
4. Install brake booster to brake pedal assembly nuts and tighten to the specified torque.
5. Connect active booster and delta stroke s ensor harness connectors to brake booster.
6. Connect vacuum hose to brake booster.
7. Install master cylinder assembly to brake booster. Refer to BR-25, "
Removal and Installation".
8. Adjust the height and play of brake pedal. Refer to BR-15, "
Inspection and Adjustment".
9. Tighten lock nut of input rod to specification.
10. Install the instrument lower panel LH. Refer to IP-11, "
Exploded View".
11. Secure A/C line into clips.
12. Install cowl top assembly. Refer to EXT-18, "
Removal and Installation".
13. Install air duct and resonator assembly. Refer to EM-25, "
Removal and Installation".
14. Refill with new brake fluid and bleed air. Refer to BR-17, "
Bleeding Brake System".
Output rod length : Refer to
BR-46, "
Brake
Booster".
SBR208E
Input rod length (B) : Refer to BR-46, "Brake
Booster".
WFIA0382E
Revision: March 2010 2008 QX56

FRONT DISC BRAKEBR-33
< ON-VEHICLE REPAIR >
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3. Install brake hose to brake caliper assembly using new copper washers. Align the brake hose to the projection as shown and
tighten union bolts to the specified torque.
CAUTION:
• Do not reuse copper washers.
• Securely attach brake hose to projection on cylinderbody.
4. Refill with new brake fluid and bleed air. Refer to BR-17, "
Bleeding Brake System".
5. Check front disc brake for drag and correct as necessary.
6. Install front wheel and tires. Refer to WT-48, "
Rotation".
SFIA2431E
Revision: March 2010 2008 QX56

BR-36
< ON-VEHICLE REPAIR >
REAR DISC BRAKE
Removal and Installation of Brake Caliper and Disc Rotor
INFOID:0000000004894522
WARNING:
Clean dust on caliper and brake pad with a vacuum dust collector to minimize the hazard of air borne
particles or other materials.
CAUTION:
• While removing cylinder body, do not depress brake pedal because piston will pop out.
• Do not damage piston boot.
• Keep rotor free from brake fluid.
• Refill with new specified brake fluid.
• Burnish brake contact surface after refinishing or re placing rotors, after replacing pads, or it a soft
pedal occurs at very low mileage. Refer to BR-35, "
Brake Burnishing Procedure".
REMOVAL
1. Remove rear wheel and tires. Refer to WT-48, "Rotation".
2. Fasten disc rotor using wheel nut.
3. Drain brake fluid as necessary. Refer to BR-17, "
Drain and Refill".
4. Remove union bolt and cylinder body bolts, then remove cylin- der body.
NOTE:
Discard the copper washers, do not reuse.
5. Apply matching marks to disc rotor and wheel hub assembly if the disc rotor is to be reused, then remove disc rotor.
CAUTION:
Put matching marks on wheel hub assembly and disc rotor
if the disc rotor is to be reused.
INSTALLATION
1. If reusing the disc rotor, use the matching marks to align disc rotor on the wheel hub assembly, then install
disc rotor using a wheel nut to hold it in place.
CAUTION:
Use matching marks on wheel hub assembly and di sc rotor if the disc rotor is to be reused.
2. Install cylinder body and tighten cylinder body bolts to specification. CAUTION:
Before installing cylinder body to the vehic le, wipe off mating surface of cylinder body.
3. Install brake hose to cylinder body with new copper washers and tighten union bolt to specification.
CAUTION:
• Do not reuse copper washers.
• Securely attach brake hose to projection on cylinderbody.
4. Refill with new brake fluid and bleed. Refer to BR-17, "
Bleeding
Brake System".
5. Check rear disc brake for drag and correct as necessary.
6. Install rear wheel and tires. Refer to WT-48, "
Rotation".
1. Union bolt 2. Brake hose 3. Copper washer
4. Cap 5. Bleed valve 6. Sliding pin bolt
7. Cylinder body 8. Piston seal9. Piston
10. Piston boot 11. Knuckle slide 12. Sliding sleeve boot
13. Sliding sleeve B: Brake fluidR: Rubber grease
M: Molykote 7439 grease Front
LFIA0211E
SFIA1137E
Revision: March 2010 2008 QX56

BRC-104
< SYMPTOM DIAGNOSIS >[VDC/TCS/ABS]
UNEXPECTED PEDAL REACTION
UNEXPECTED PEDAL REACTION
Diagnosis ProcedureINFOID:0000000001686376
1.CHECK BRAKE PEDAL STROKE
Check brake pedal stroke. Refer to BR-15, "
Inspection and Adjustment".
Is the stroke too large?
YES >> • Bleed air from brake tube and hose. Refer to BR-17, "Bleeding Brake System".
• Check brake pedal, brake booster, and master cylinder for mount play, looseness, brake system fluid leakage, etc. Refer to BR-15, "
Inspection and Adjustment" (brake pedal), BR-12, "On
Board Inspection" (master cylinder), BR-10, "Inspection" (brake booster).
NO >> GO TO 2
2.CHECK FUNCTION
Disconnect ABS actuator and electric unit (control unit) c onnector to deactivate ABS. Check if braking force is
normal in this condition. Connect connector after inspection.
Is the inspection result normal?
YES >> Normal
NO >> Check brake system.
Revision: March 2010 2008 QX56