engine cooling INFINITI FX35 2006 Owner's Manual
Page 1210 of 4462
CO-16
[VQ35DE]
RADIATOR
Revision: 2006 December 2006 FX35/FX45
Pull negative-pressure valve to open it, and make sure that it
close completely when released.
–Make sure that there is no dirt or damage on the valve seat of
radiator cap negative-pressure valve.
–Make sure that there are no unusualness in the opening and
closing conditions of negative-pressure valve.
Check radiator cap relief pressure.
–When connecting radiator cap to the radiator cap tester (com-
mercial service tool) and the radiator cap tester adapter [SST],
apply engine coolant to the cap seal surface.
Replace radiator cap if there is an unusualness related to the above three.
CAUTION:
When installing radiator cap, thoroughly wipe out the radiator filler neck to remove any waxy residue
or foreign material.
Checking RadiatorNBS003JZ
Check radiator for mud or clogging. If necessary, clean radiator as follows.
Be careful not to bend or damage radiator fins.
When radiator is cleaned without removal, remove all surrounding parts such as radiator cooling fan
assembly and horns. Then tape harness and connectors to prevent water from entering.
1. Apply water by hose to the back side of the radiator core vertically downward.
2. Apply water again to all radiator core surfaces once per minute.
3. Stop washing if any stains no longer flow out from radiator.
4. Blow air into the back side of radiator core vertically downward.
Use compressed air lower than 490 kPa (5 kg/cm2 , 71 psi) and keep distance more than 30 cm (11.81
in).
5. Blow air again into all the radiator core surfaces once per minute until no water sprays out.
SMA967B
Standard:
78 - 98 kPa (0.8 - 1.0 kg/cm
2 , 11 - 14 psi)
Limit:
59 kPa (0.6 kg/cm
2 , 9 psi)
SLC755A
Page 1215 of 4462
COOLING FAN CO-21
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45
COOLING FANPFP:21140
ComponentsNBS003K2
Removal and Installation NBS003K3
REMOVAL
1. Remove air duct (inlet), power duct and air cleaner case assembly. Refer to EM-17, "AIR CLEANER AND
AIR DUCT" .
2. Disconnect harness connector from fan motors, and move harness to aside.
3. Remove radiator cooling fan assembly.
CAUTION:
Be careful not to damage or scratch on radiator core.
INSTALLATION
Installation is the reverse order of removal.
INSPECTION AFTER INSTALLATION
Make sure that fan motors operate normally.
NOTE:
Cooling fans are controlled by ECM. For details, refer to EC-497, "
DTC P1217 ENGINE OVER TEMPERA-
TURE" .
Disassembly and Assembly NBS003K4
DISASSEMBLY
1. Remove cooling fans (RH and LH) from fan motors.
2. Remove fan motors from fan shroud.
INSPECTION AFTER DISASSEMBLY
Cooling Fan
Inspect cooling fan for crack or unusual bend.
If anything is found, replace cooling fan.
ASSEMBLY
Assemble in the reverse order of disassembly.
CAUTION:
Cooling fans and fan motors are different between RH and LH. Be careful not to misassemble them.
1. Cooling fan (RH) 2. Cooling fan (LH) 3. Fan shroud
4. Fan motor
PBIC3047E
Page 1228 of 4462
CO-34
[VK45DE]
OVERHEATING CAUSE ANALYSIS
Revision: 2006 December 2006 FX35/FX45
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartNBS003KF
Symptom Check items
Cooling sys-
tem parts
malfunction Poor heat transfer
Water pump malfunction Worn or loose drive belt
—
Thermostat and water con-
trol valve stuck closed —
Damaged fins Dust contamination or
paper clogging
Physical damage
Clogged radiator cooling
tube Excess foreign material
(rust, dirt, sand, etc.)
Reduced air flow Cooling 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 coolant Engine coolant leaks Cooling hose
Loose clamp
Cracked hose
Water pump Poor sealing
Radiator cap Loose
Poor sealing
Radiator O-ring for damage, deterio-
ration or improper fitting
Cracked radiator tank
Cracked radiator core
Reservoir tank Cracked reservoir tank
Overflowing reservoir tank Exhaust gas leaks into
cooling system Cylinder head deterioration
Cylinder head gasket dete-
rioration
Page 1232 of 4462
CO-38
[VK45DE]
ENGINE COOLANT
Revision: 2006 December 2006 FX35/FX45
ENGINE COOLANTPFP:KQ100
InspectionNBS003KI
LEVEL CHECK
Check if the reservoir tank engine coolant level is within the
“MIN” to “MAX” when engine is cool.
Adjust the engine coolant level as necessary.
LEAK CHECK
To check for leaks, apply pressure to the cooling system with
radiator cap tester (commercial service tool) and radiator cap
tester adapter (SST).
WARNING:
Do not remove radiator cap when engine is hot. Serious
burns could occur from high-pressure engine coolant
escaping from thermostat housing.
CAUTION:
Higher testing pressure than specified may cause radiator
damage.
NOTE:
In a case engine coolant decreases, replenish radiator with engine coolant.
If anything is found, repair or replace damaged parts.
Changing Engine CoolantNBS003KJ
WARNING:
To avoid being scalded, do not change engine coolant when engine is hot.
Wrap a thick cloth around radiator cap and carefully remove radiator cap. First, turn radiator cap a
quarter of a turn to release built-up pressure. Then turn radiator cap all the way.
DRAINING ENGINE COOLANT
1. Remove front engine undercover with power tool.
2. Open radiator drain plug at the bottom of radiator, and then remove radiator cap.
When draining all of engine coolant in the system, open water drain plugs on cylinder block. Refer
to EM-249, "
DISASSEMBLY" .
3. Remove reservoir tank as necessary, and drain engine coolant and clean reservoir tank before installing.
4. Check drained engine coolant for contaminants such as rust, corrosion or discoloration. If contaminated, flush the engine cooling system. Refer to CO-40, "
FLUSHING COOLING SYSTEM" .
SMA412B
Testing pressure : 157 kPa (1.6 kg/cm2 , 23 psi)
PBIC1528E
SBIA0444E
Page 1234 of 4462
CO-40
[VK45DE]
ENGINE COOLANT
Revision: 2006 December 2006 FX35/FX45
9. Repeat steps 4 through 7 two or more times with radiator cap installed until engine coolant level no longer drops.
10. Check cooling system for leaks with engine running.
11. Warm up engine, and check for sound of engine coolant flow while running engine from idle up to 3,000 rpm with heater temperature controller set at several position between “COOL” and “WARM”.
Sound may be noticeable at heater unit.
12. Repeat step 11 three times.
13. If sound is heard, bleed air from cooling system by repeating steps 4 through 7 until engine coolant level no longer drops.
FLUSHING COOLING SYSTEM
1. Install reservoir tank, and radiator drain plug.
CAUTION:
Be sure to clean drain plug and install with new O-ring.
If water drain plugs on cylinder block are removed, close and tighten them. Refer to EM-253,
"ASSEMBLY" .
2. Remove air relief plug on heater hose.
3. Fill thermostat housing with water until water spills from the air relief hole, then close air relief plug. Fill thermostat housing and reservoir tank with water and reinstall radiator cap.
4. Run engine and warm it up to normal operating temperature.
5. Rev engine two or three times under no-load.
6. Stop engine and wait until it cools down.
7. Drain water from the system. Refer to CO-38, "
DRAINING ENGINE COOLANT" .
8. Repeat steps 1 through 7 until clear water begins to drain from radiator. Radiator drain plug:
: 1.19 N·m (0.12 kg-m, 11 in-lb)
PBIC1530E
Page 1243 of 4462
COOLING FAN CO-49
[VK45DE]
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Revision: 2006 December 2006 FX35/FX45
COOLING FANPFP:21140
Components (Crankshaft Driven type)NBS005RY
Removal and InstallationNBS003KO
REMOVAL
1. Remove air duct (inlet). Refer to EM-177, "AIR CLEANER AND AIR DUCT" .
2. Remove engine front undercover with power tool.
3. Remove radiator shroud (lower). Refer to CO-41, "
RADIATOR" .
4. Remove drive belts. Refer to EM-174, "
DRIVE BELTS" .
5. Remove fan coupling and cooling fan assembly. CAUTION:
Do not damage or scratch radiator core when removing.
6. Remove cooling fan from fan coupling.
INSPECTION AFTER REMOVAL
Fan Coupling
Inspect fan coupling for oil leakage and bimetal conditions.
If anything is found, replace fan coupling.
Cooling Fan
Inspect cooling fan for crack or unusual bend.
If anything is found, replace cooling fan.
INSTALLATION
Note the following, install in the reverse order of removal.
Install cooling fan with its front mark “F” facing front of vehicle. Refer to CO-49, "Removal and Installation"
.
1. Cooling fan 2. Fan coupling 3. Fan pulley
4. Water pump
PBIC1537E
SLC072
Page 1244 of 4462
CO-50
[VK45DE]
COOLING FAN
Revision: 2006 December 2006 FX35/FX45
Components (Motor Driven Type)NBS005RZ
Removal and InstallationNBS003KP
REMOVAL
1. Remove front grille. Refer to EI-22, "FRONT GRILLE" .
2. Disconnect harness connector from fan motor.
3. Remove cooling fan assembly. CAUTION:
Do not damage or scratch A/C condenser when removed.
INSTALLATION
Install in the reverse order of removal.
Cooling fan is controlled by ECM. For details. Refer to EC-1171, "DTC P1217 ENGINE OVER TEMPER-
ATURE" .
Disassembly and Assembly (Motor Driven Type)NBS003KQ
DISASSEMBLY
1. Remove cooling fan from fan motor.
2. Remove fan motor from fan grille.
INSPECTION AFTER DISASSEMBLY
Cooling Fan
Inspect cooling fan for crack or unusual bend.
If anything is found, replace cooling fan.
ASSEMBLY
Assemble in the reverse order of disassembly.
1. Cooling fan 2. Fan grille 3. Fan motor
PBIC1666E
Page 1245 of 4462
WATER PUMP CO-51
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Revision: 2006 December 2006 FX35/FX45
WAT E R P U MPPFP:21020
ComponentsNBS005S0
Removal and InstallationNBS003KR
CAUTION:
When removing water pump, be careful not to get engine coolant on drive belts.
Water pump can not be disassembled and should be replaced as a unit.
After installing water pump, connect hose and clamp securely, then check for leaks using radiator
cap tester (commercial service tool) and radiator cap tester adapter [SST: EG17650301 (J33984-
A)].
REMOVAL
1. Drain engine coolant from drain plugs on radiator and both side of cylinder block. Refer to CO-38, "Chang-
ing Engine Coolant" and EM-249, "DISASSEMBLY" .
CAUTION:
Perform this step when engine is cold.
Do not spill engine coolant on drive belts.
2. Remove following parts:
Engine front undercover
Air duct (inlet); Refer to EM-177, "AIR CLEANER AND AIR DUCT" .
Alternator, water pump and A/C compressor belt; Refer to EM-174, "DRIVE BELTS" .
3. Remove fan coupling with cooling fan, and then water pump pulley.
4. Remove water pump.
Engine coolant will leak from cylinder block, so have a receptacle ready under vehicle.
CAUTION:
Handle the water pump vane so that it does not contact any other parts.
Do not disassemble water pump.
1. Water pump pulley 2. Water pump 3. Gasket
PBIC1538E
Page 1480 of 4462
EC-96
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
Fail-Safe ChartNBS003LZ
When the DTC listed below is detected, the ECM enters fail-safe mode and the MIL lights up.
When there is an open circuit on MIL circuit, the ECM cannot warn the driver by MIL lighting up when
there is malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected
as NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by
means of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands
the driver to repair the malfunction.
DTC No. Detected items Engine operating condition in fail-safe mode
P0102
P0103 Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118 Engine coolant tempera-
ture sensor circuit Engine coolant temperature will be determined by ECM based on the time after turning
ignition switch ON or START.
CONSULT-II displays the engine coolant temperature decided by ECM.
Condition Engine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned
ON or START 40
°C (104 °F)
More than approx. 4 minutes after
ignition ON or START 80
°C (176 °F)
Except as shown above 40 - 80
°C (104 - 176 °F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling
fan operates while engine is running.
P0122
P0123
P0222
P0223
P2135 Throttle position sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
P0643 Sensor power supply ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2100
P2103 Throttle control motor relay ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2101 Electric throttle control function ECM stops the electric throttle control actuator control, throttle valve is maintained at a
fixed opening (approx. 5 degrees) by the return spring.
P2118 Throttle control motor ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return spring.
P2119 Electric throttle control actuator (When electric throttle control actuator does not function properly due to the return spring
malfunction:)
ECM controls the electric throttle actuator by regulating the throttle opening around the
idle position. The engine speed will not rise more than 2,000 rpm.
(When throttle valve opening angle in fail-safe mode is not in specified range:)
ECM controls the electric throttle control actuator by regulating the throttle opening to 20
degrees or less.
(When ECM detects the throttle valve is stuck open:)
While the vehicle is driving, it slows down gradually by fuel cut. After the vehicle stops,
the engine stalls.
The engine can restart in N or P position, and engine speed will not exceed 1,000 rpm or
more.
P2122
P2123
P2127
P2128
P2138 Accelerator pedal position
sensor The ECM controls the electric throttle control actuator in regulating the throttle opening in
order for the idle position to be within +10 degrees.
The ECM regulates the opening speed of the throttle valve to be slower than the normal
condition.
So, the acceleration will be poor.
Engine operating condition in fail-safe mode Engine speed will not rise more than 2,500 rpm due to the fuel cut
Page 1484 of 4462
EC-100
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2006 December 2006 FX35/FX45
1 - 6: The numbers refer to the order of inspection. Va l v e
mecha-
nism Timing chain
55555 55 5 EM-64
Camshaft
EM-83
Intake valve timing controlEM-64
Intake valve
3 EM-101
Exhaust valve
Exhaust Exhaust manifold/Tube/Muffler/ Gasket 55555 55 5 EM-26
,
EX-
3Three way catalyst
Lubrica-
tion Oil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler 55555 55 5 EM-30
,
LU-
17 , LU-10 ,
LU-14
Oil level (Low)/Filthy oil LU-7
Cooling
Radiator/Hose/Radiator filler cap
55555 55 45 CO-14,
CO-17
Thermostat 5 CO-27
Water pumpCO-22
Water galleryCO-29
Cooling fan 5EC-228
Coolant level (Low)/Contami-
nated coolant 5
CO-11
IVIS (Infiniti Vehicle Immobilizer System —
NATS) 11
EC-53 or
BL-205
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA