Ins INFINITI QX56 2004 Factory Service Manual
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BRC-66
[VDC/TCS/ABS]
ACTUATOR AND ELECTRIC UNIT (ASSEMBLY)
Revision: August 20072004 QX56
ACTUATOR AND ELECTRIC UNIT (ASSEMBLY)PFP:47660
Removal and InstallationEFS003RQ
REMOVAL
1. Disconnect the negative battery terminal.
2. Remove the cowl top extension. Refer to EI-18, "
Removal and Installation" .
3. Drain the brake fluid. Refer to BR-10, "
Drain and Refill" .
4. Disconnect the actuator harness from the ABS actuator and electric unit (control unit).
CAUTION:
To remove the brake tubes, use a flare nut wrench to prevent the flare nuts and brake tubes from
being damaged.
Be careful not to splash brake fluid on painted areas.
5. Disconnect the brake tubes.
6. Remove the three bolts and remove the ABS actuator and electric unit (control unit).
WFIA0241E
1. To rear left 2. To rear right 3. To front left
4. To front right 5. From the master cylinder secondary side 6. From the master cylinder primary side
7. ABS actuator and electric unit (control
unit)8. Harness connector
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ACTUATOR AND ELECTRIC UNIT (ASSEMBLY)
BRC-67
[VDC/TCS/ABS]
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Revision: August 20072004 QX56
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
To install, use a flare nut wrench (commercial service tool).
Always tighten brake tubes to specification when installing. Refer to BR-12, "BRAKE PIPING AND
HOSE" .
Never reuse drained brake fluid.
After installation of the ABS actuator and electric unit (control unit), refill brake system with new
brake fluid. Then bleed the air from the system. Refer to BR-11, "
Bleeding Brake System" .
After installation of ABS actuator, adjust steering angle sensor. Refer to BRC-62, "Adjustment of
Steering Angle Sensor Neutral Position" .
After installation of ABS actuator, calibrate the decel G sensor. Refer to BRC-62, "Calibration of
Decel G Sensor" .
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BRC-68
[VDC/TCS/ABS]
STEERING ANGLE SENSOR
Revision: August 20072004 QX56
STEERING ANGLE SENSORPFP:25554
Removal and InstallationEFS003RR
The steering angle sensor is an integral part of the spiral cable. Refer to SRS-47, "Removal and Installation" .
CAUTION:
After installation of spiral cable, adjust steering angle sensor. Refer to BRC-62, "
Adjustment of Steer-
ing Angle Sensor Neutral Position" .
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G SENSOR
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[VDC/TCS/ABS]
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Revision: August 20072004 QX56
G SENSORPFP:47930
Removal and InstallationEF S0 03 RS
REMOVAL
1. Remove center console. Refer to IP-10, "INSTRUMENT PANEL ASSEMBLY" .
2. Remove yaw rate/side/decel G sensor attaching nuts.
CAUTION:
Do not use power tools to remove or install yaw rate/side/
decel G sensor.
Do not drop or strike the yaw rate/side/decel G sensor.
3. Disconnect harness connector and remove the yaw rate/side/
decel G sensor.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
Do not drop or strike the yaw rate/side/decel G sensor.
After installation, calibrate the decel G sensor. Refer to BRC-62, "Calibration of Decel G Sensor" .
WFIA0230E
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CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
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SECTION CO
A
CO
Revision: August 20072004 QX56 PRECAUTIONS .......................................................... 2
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 2
PREPARATION ........................................................... 3
Special Service Tools ............................................... 3
Commercial Service Tools ........................................ 3
OVERHEATING CAUSE ANALYSIS .......................... 4
Troubleshooting Chart .............................................. 4
COOLING SYSTEM .................................................... 6
Cooling Circuit .......................................................... 6
System Drawing ....................................................... 7
ENGINE COOLANT .................................................... 8
Inspection ................................................................. 8
LEVEL CHECK ..................................................... 8
CHECKING COOLING SYSTEM FOR LEAKS ..... 8
CHECKING RESERVOIR CAP ............................. 8
CHECKING RADIATOR CAP ................................ 8
Changing Engine Coolant ........................................ 8
DRAINING ENGINE COOLANT ........................... 8
REFILLING ENGINE COOLANT .......................... 9
FLUSHING COOLING SYSTEM ........................... 9
RADIATOR ................................................................ 10
Removal and Installation ........................................ 10
REMOVAL ........................................................... 10
INSTALLATION ................................................... 12
INSPECTION AFTER INSTALLATION ............... 12
Checking Radiator .................................................. 12ENGINE COOLING FAN ........................................... 13
Removal and Installation (Crankshaft Driven Type) ... 13
REMOVAL ........................................................... 13
INSPECTION AFTER REMOVAL ....................... 13
INSTALLATION ................................................... 13
INSPECTION AFTER INSTALLATION ................ 13
Removal and Installation (Motor Driven Type) ....... 14
REMOVAL ........................................................... 14
INSTALLATION ................................................... 14
WATER PUMP .......................................................... 15
Removal and Installation ........................................ 15
REMOVAL ........................................................... 15
INSPECTION AFTER REMOVAL ....................... 15
INSTALLATION ................................................... 15
INSPECTION AFTER INSTALLATION ................ 16
THERMOSTAT AND WATER PIPING ...................... 17
Removal and Installation ........................................ 17
REMOVAL ........................................................... 17
INSPECTION AFTER REMOVAL ....................... 18
INSTALLATION ................................................... 18
INSPECTION AFTER INSTALLATION ................ 18
SERVICE DATA AND SPECIFICATIONS (SDS) ...... 19
Standard and Limit .................................................. 19
ENGINE COOLANT CAPACITY (APPROXI-
MATE) .................................................................. 19
THERMOSTAT .................................................... 19
RADIATOR .......................................................... 19
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CO-2Revision: August 2007
PRECAUTIONS
2004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EBS00I4Q
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.
WAR NIN G:
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.
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CO-4Revision: August 2007
OVERHEATING CAUSE ANALYSIS
2004 QX56
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartEBS00I4T
Symptom Check items
Cooling sys-
tem parts
malfunctionPoor heat transferWater pump malfunction Worn or loose drive belt
— Thermostat stuck closed —
Damaged finsDust contamination or
paper clogging
Physical damage
Clogged radiator cooling
tubeExcess foreign material
(rust, dirt, sand, etc.)
Water cut valve malfunctionExcess foreign material
(rust, dirt, sand, etc.), phys-
ical damage
Reduced air flowCooling fan does not oper-
ate
Fan assembly — High resistance to fan rota-
tion
Damaged fan blades
Damaged radiator shroud — — —
Improper engine coolant
mixture ratio—— —
Poor engine coolant quality — Engine coolant density —
Insufficient engine coolantEngine coolant leaksCooling hoseLoose clamp
Cracked hose
Water pump Poor sealing
Radiator capLoose
Poor sealing
RadiatorO-ring for damage, deterio-
ration or improper fitting
Cracked radiator tank
Cracked radiator core
Reservoir tank Cracked reservoir tank
Overflowing reservoir tankExhaust gas leaks into
cooling systemCylinder head deterioration
Cylinder head gasket dete-
rioration
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OVERHEATING CAUSE ANALYSIS
CO-5
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Revision: August 20072004 QX56
Except cool-
ing system
parts mal-
function— Overload on engineAbusive drivingHigh engine rpm under no
load
Driving in low gear for
extended time
Driving at extremely high
speed
Powertrain system mal-
function
— Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flowBlocked bumper —
— Blocked radiator grilleInstalled car brassiere
Mud contamination or
paper clogging
Blocked radiator —
Blocked condenser
Blocked air flow
Installed large fog lamp Symptom Check items
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CO-8Revision: August 2007
ENGINE COOLANT
2004 QX56
ENGINE COOLANTPFP:KQ100
InspectionEBS00I4W
LEVEL CHECK
Check if the engine coolant reservoir tank level is within MIN to
MAX level when engine is cool.
Adjust engine coolant level as necessary.
CHECKING COOLING SYSTEM FOR LEAKS
WAR NIN G:
Never remove the radiator or reservoir cap when the engine is hot. Serious burns could occur from
high-pressure engine coolant escaping from the radiator or reservoir.
To check for leakage, apply pressure to the cooling system at
the reservoir filler neck using suitable tool and Tool.
CAUTION:
Higher pressure than specified may cause radiator damage.
NOTE:
In case that engine coolant decreases, replenish cooling system
with engine coolant.
If any concerns are found, repair or replace damaged parts.
CHECKING RESERVOIR CAP
Check reservoir cap relief pressure using suitable tool and Tool.
NOTE:
Apply engine coolant to the cap seal.
Replace the reservoir cap if there is any damage in the nega-
tive-pressure valve, or if the open-valve pressure is outside of
the limit.
CHECKING RADIATOR CAP
Inspect the radiator cap.
NOTE:
Thoroughly wipe out the radiator filler neck to remove any waxy residue or foreign material.
Replace the cap if the metal plunger cannot be seen around the edge of the black rubber gasket.
Replace the cap if deposits of waxy residue or other foreign material are on the black rubber gasket or the
metal retainer.
Changing Engine CoolantEBS00I4X
Refer to MA-12, "Changing Engine Coolant" .
DRAINING ENGINE COOLANT
Refer to MA-12, "DRAINING ENGINE COOLANT" .
SM A41 2B
Tool number : EG17650301 (J-33984-A)
Leakage test pressure : 137 kPa (1.4 kg/cm, 20 psi)
WBIA0612E
Tool number : EG17650301 (J-33984-A)
Standard
: 95 - 125 kPa (0.97 - 1.28 kg/cm
2 , 14 - 18
psi)
WBIA0611E
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CO-10Revision: August 2007
RADIATOR
2004 QX56
RADIATORPFP:21400
Removal and InstallationEBS00I4Y
WAR NIN G:
Never remove the radiator cap when the engine is hot. Serious burns could occur from high-pressure
engine coolant escaping from the radiator.
REMOVAL
CAUTION:
Perform when the engine is cold.
1. Remove engine room cover. Refer to EM-11, "
ENGINE ROOM COVER" .
2. Drain engine coolant from the radiator. Refer to MA-12, "
DRAINING ENGINE COOLANT" .
3. Remove air cleaner and air duct assembly. Refer to EM-14, "
REMOVAL" .
4. Disconnect A/T fluid cooler hoses.
Install blind plug to avoid leakage of A/T fluid.
5. Disconnect radiator upper and lower hoses from radiator.
WBIA0519E
1. Radiator 2. Bolt 3. Mounting rubber
4. A/T fluid cooler hose 5. Radiator hose (lower) 6. Flaps
7. Radiator shroud (upper) 8. Radiator shroud (lower) 9. Drain plug
10. Radiator hose (upper) 11. Reservoir tank hose 12. By-pass hose
13. Reservoir tank 14. Reservoir tank cap