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CONTENTS
ENGINE COOLING SYSTEM
PRECAUTION ....... ........................................2
PRECAUTIONS .............................................. .....2
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ......
2
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ............................... ......
2
Precaution for Liquid Gasket .....................................3
PREPARATION ............................................4
PREPARATION .............................................. .....4
Special Service Tool ........................................... ......4
Commercial Service Tool ..........................................4
FUNCTION DIAGNOSIS ...............................6
COOLING SYSTEM ....................................... .....6
Cooling Circuit ..................................................... ......6
Schematic .................................................................7
OVERHEATING CAUSE ANALYSIS ..................8
Troubleshooting Chart ...............................................8
ON-VEHICLE MAINTENA NCE ....................10
ENGINE COOLANT ....................................... ....10
Inspection ............................................................ ....10
Changing Engine Coolant .......................................11
RADIATOR ........................................................14
Checking Radiator ............................................... ....14
ON-VEHICLE REPAIR .................................15
RADIATOR ....... .................................................15
Exploded View ..................................................... ....15
Removal and Installation .........................................15
ENGINE COOLING FAN ...................................18
Exploded View .........................................................18
Removal and Installation (Crankshaft Driven
Type) .......................................................................
18
Removal and Installation (Motor Driven Type) ........19
WATER PUMP ..................................................20
Exploded View .........................................................20
Removal and Installation .........................................20
THERMOSTAT AND WATER PIPING ..............22
Exploded View .........................................................22
Removal and Installation .........................................22
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... ...
24
SERVICE DATA AND SPECIFICATIONS
(SDS) .................................................................
24
Standard and Limit .............................................. ....24
Revision: April 20092010 QX56
CO-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005260136
The Supplemental Restraint System such as “A IR 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 w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, 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 in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005260137
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: April 20092010 QX56
CO-8
< FUNCTION DIAGNOSIS >
OVERHEATING CAUSE ANALYSIS
OVERHEATING CAUSE ANALYSIS
Troubleshooting ChartINFOID:0000000005149040
SymptomCheck items
Cooling sys-
tem parts
malfunction Poor heat transfer
Water pump malfunction Worn or loose drive belt
—
Thermostat stuck closed Coolant circulation
Damaged fins
Dust contamination or pa-
per clogging
Physical damage
Clogged radiator cooling
tube Excess foreign material
(rust, dirt, sand, etc.)
Water cut valve malfunction Excess foreign material
(rust, dirt, sand, etc.), phys-
ical damage
Reduced air flow Cooling fan does not oper-
ate
Fan assembly —
High resistance to fan rota-
tion
Damaged fan blades
Damaged radiator shroud —Radiator shroud —
Improper engine coolant
mixture ratio —
Coolant viscosity —
Poor engine coolant quality —Engine coolant density —
Insufficient engine coolant Engine coolant leaksCooling hose
Loose clamp
Cracked hose
Water pump Poor sealing
Radiator cap Loose
Poor sealing
Radiator O-ring for da
mage, deterio-
ration or improper fitting
Cracked radiator tank
Cracked radiator core
Reservoir tank Cracked reservoir tank
Overflowing reservoir tank Exhaust gas leaks into cool-
ing system Cylinder head deterioration
Cylinder head gasket deteri-
oration
Revision: April 20092010 QX56
ENGINE COOLANTCO-11
< ON-VEHICLE MAINTENANCE >
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Inspect the radiator cap.
NOTE:
Thoroughly wipe out the radiator filler
neck to remove any waxy resi-
due 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 mate- rial are on the black rubber gasket or the metal retainer.
• Pull negative-pressure valve to open it and make sure that it closes completely when released.
• Make sure that there is no dirt or damage on the valve seat of radi-
ator cap negative-pressure valve.
• Make sure that there are no unusualness in the opening and clos- ing conditions of negative-pressure valve.
Changing Engine CoolantINFOID:0000000005149042
WARNING:
• To avoid being scalded, never change the coolant when the engine is hot.
• Wrap a thick cloth around the cap to carefully remo ve the cap. First, turn the cap a quarter of a turn
to release any built-up pressure, then push down and turn the cap all the way to remove it.
DRAINING ENGINE COOLANT
1. Turn ignition switch ON and set temperature control lever all the way to HOT position or the highest tem-
perature position. Wait 10 seconds and turn ignition switch OFF.
2. Remove the engine front undercover using power tool.
3. Open the radiator drain plug at the bottom of the radiator, and remove the radiator filler cap. This is the only step required
when partially draining the cooling system (radiator only).
CAUTION:
Do not to allow the coolant to contact the drive belts.
4. When draining all of the coolant in the system for engine removal or repair, it is necessary to drain the cylinder block.
Remove the RH cylinder block drain plug to drain the right bank
and the oil cooler hose to drain the left bank as shown.
PBIC2816E
SMA967B
WBIA0391E
PBIC0146E
Revision: April 20092010 QX56
CO-16
< ON-VEHICLE REPAIR >
RADIATOR
5. Disconnect the radiator lower hose from the radiator.CAUTION:
Do not allow coolant to contact drive belts.
6. Remove the lower radiator shroud. • Release the tabs, pull lower radiator shroud rearwards anddown to remove.
7. Disconnect the radiator upper hose and the coolant reservoir hose from the radiator. CAUTION:
Do not allow coolant to contact drive belt.
8. Remove the radiator shroud upper bolts and remove the radiator shroud upper (A).
9. Remove the upper radiator mounting bolts and rubbers.
10. Remove the A/C condenser bolts and brackets. NOTE:
Lift A/C condenser up and forward to remove from radiator.
11. Remove A/T oil cooler bolts and oil cooler from radiator and position aside.
WBIA0407E
WBIA0695E
WBIA0395E
WBIA0396E
Revision: April 20092010 QX56
CO-18
< ON-VEHICLE REPAIR >
ENGINE COOLING FAN
ENGINE COOLING FAN
Exploded ViewINFOID:0000000005149046
Crankshaft Driven Type
Removal and Installation (Crankshaft Driven Type)INFOID:0000000005149047
REMOVAL
1. Partially drain engine coolant from the radiator. Refer to CO-11, "Changing Engine Coolant".
2. Remove the lower and upper radiator shrouds. Refer to CO-15, "
Exploded View".
3. Remove the drive belt. Refer to EM-13, "
Removal and Installation".
4. Remove the cooling fan.
5. Remove the fan bracket, if necessary.
INSPECTION AFTER REMOVAL
Fan Coupling
• Inspect fan coupling for oil leakage and bimetal conditions.
• If there are any unusual concerns, replace the fan coupling.
Fan Bracket
• Visually check that there is no significant looseness in the fan bracket shaft, and that it turns smoothly by hand.
• If there are any unusual concerns, replace the fan bracket.
Cooling Fan Pulley
• Inspect cooling fan pulley.
• If there are any unusual concerns, replace the cooling fan pulley.
AWBIA0812GB
1. Cooling fan 2. Fan coupling3. Fan bracket
4. Cooling fan pulley A. Front mark Engine front
SLC072
WBIA0418E
Revision: April 20092010 QX56
CO-20
< ON-VEHICLE REPAIR >
WATER PUMP
WATER PUMP
Exploded ViewINFOID:0000000005149049
Removal and InstallationINFOID:0000000005149050
CAUTION:
• When removing water pump, be careful not to get engine coolant on drive belt.
• Water pump cannot be disassembled and should be replaced as a unit.
REMOVAL
1. Drain engine coolant from the radiator. Refer to CO-11, "Changing Engine Coolant".
CAUTION:
Perform when the engine is cold.
2. Remove the engine cooling fan (crankshaft driven type). Refer to CO-18, "
Removal and Installation
(Crankshaft Driven Type)".
3. Remove the water pump pulley.
4. Remove the water pump. • Engine coolant will leak from the cylinder block, so have a receptacle ready below.
CAUTION:
Handle water pump vane so that it does not contact any other parts.
INSPECTION AFTER REMOVAL
• Visually check that there is no signi ficant dirt or rust on the water
pump body and vane.
• Make sure there is no looseness in the vane shaft, and that it turns smoothly when rotated by hand.
• Replace the water pump assembly, if necessary.
INSTALLATION
Installation is in the reverse order of removal.
• After installation bleed the air from the cooling system. Refer to CO-11, "
Changing Engine Coolant".
1. Gasket2. Water pump3. Water pump pulley
KBIA2543E
KBIA2552E
Revision: April 20092010 QX56
DEF-2
PASSENGER SIDE DOOR MIRROR DEFOG-
GER DOES NOT OPERATE. ............................
41
Diagnosis Procedure ........................................... ...41
REAR WINDOW DEFOGGER SWITCH DOES
NOT LIGHT, BUT REAR WINDOW DEFOG-
GER OPERATES ...............................................
42
Diagnosis Procedure ........................................... ...42
PRECAUTION .............................................43
PRECAUTIONS .............................................. ...43
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" .............................................................. ...
43
Precaution Necessary for Steering Wheel Rota-
tion After Battery Disconnect ..................................
43
Handling for Adhesive and Primer ..........................44
ON-VEHICLE REPAIR ...............................45
REAR WINDOW DEFOGGER ........................ ...45
Filament Check .................................................... ...45
Filament Repair .......................................................45
Revision: April 20092010 QX56