engine cooling INFINITI M35 2006 Factory Owner's Guide

COOLING FAN
CO-51
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Revision: 2006 January2006 M35/M45
COOLING FANPFP:21140
ComponentsNBS004RM
Removal and InstallationNBS004RN
REMOVAL
1. Remove engine room cover (RH and LH). Refer to EM-173, "ENGINE ROOM COVER" .
2. Remove air duct (inlet) and air cleaner case assembly. Refer to EM-177, "
AIR CLEANER AND AIR
DUCT" .
3. Drain engine coolant from radiator. Refer to CO-40, "
ENGINE COOLANT" .
4. Disconnect harness connector from cooling fan control module, and move harness to aside.
5. Remove radiator hose (upper). Refer to CO-43, "
RADIATOR" .
6. Remove cooling fan assembly.
CAUTION:
Be careful not to damage or scratch on radiator core.
INSTALLATION
Note the following, and Install in the reverse order of removal.
CAUTION:
Only use genuine parts for radiator shroud and cooling fan mounting bolt and observe the specified
torque (to prevent radiator from being damaged).
INSPECTION AFTER INSTALLATION
Make sure that fan motors operate normally.
1. Sub-harness 2. Cooling fan control module 3. Sub-harness
4. Fan motor (LH) 5. Fan motor (RH) 6. Fan shroud
7. Cooling fan (RH) 8. Cooling fan (LH)
A. Apply on fan motor shaft.
Apply Genuine High Strength Lock-
ing Sealant or equivalent.
KBIA3567J

CO-52
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COOLING FAN
Revision: 2006 January2006 M35/M45
NOTE:
Cooling fans are controlled by cooling fan control module. For details. Refer to EC-1239, "
DTC P1217
ENGINE OVER TEMPERATURE" .
Disassembly and Assembly NBS004RO
DISASSEMBLY
1. Disconnect sub-harness from fan motor (RH and LH) and cooling fan control module.
2. Remove cooling fan control module from fan shroud.
CAUTION:
Handle carefully to avoid dropping and shocks.
3. Remove cooling fan mounting nuts, and then remove the cooling fan (RH and LH).
4. Remove fan motor (RH and LH).
INSPECTION AFTER DISASSEMBLY
Cooling Fan
Inspect cooling fan for crack or unusual bend.
If anything is found, replace cooling fan.
ASSEMBLY
Note the following, and assemble in the reverse order of disassembly.
CAUTION:
RH and LH cooling fans are different. Be careful not to misassemble them.
Install each fan in the following position.
Secure the sub-harness tightly to the fan shroud to prevent the fan rotation area from being loose. Right side : 4 fans
Left side : 5 fans

EC-108
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
Fail-Safe ChartNBS004T0
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 lighting up MIL 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
P0103Mass air flow sensor circuit Engine speed will not rise more than 2,400 rpm due to the fuel cut.
P0117
P0118Engine coolant tempera-
ture sensor circuitEngine 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.
ConditionEngine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned
ON or START40
C (104F)
More than approx. 4 minutes after
ignition ON or START80
C (176F)
Except as shown above40 - 80
C (104 - 176F)
(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
P2135Throttle 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
P2103Throttle 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
functionECM 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
P2138Accelerator pedal position
sensorThe 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

EC-112
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
1 - 6: The numbers refer to the order of inspection.Cooling
Radiator/Hose/Radiator filler cap
55555 55 45CO-14
,
CO-18
Thermostat 5CO-29
Water pumpCO-24
Water galleryCO-31
Cooling fan
5CO-22
Coolant level (Low)/Contami-
nated coolantCO-11
IVIS (INFINITI Vehicle Immobilizer System —
NATS)11EC-53 or
BL-248
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

TROUBLE DIAGNOSIS
EC-113
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EC
Revision: 2006 January2006 M35/M45
Engine Control Component Parts LocationNBS004T2
1. IPDM E/R 2. ICC brake hold relay
(ICC models only)3. Battery current sensor
4. Cooling fan relay 5. Power steering pressure sensor 6. Refrigerant pressure sensor
7. Intake valve timing control solenoid
valve (bank 1)8. Cooling fan motor-2 9. Cooling fan control module
10. Intake valve timing control solenoid
valve (bank 2)11. Cooling fan motor-1 12. Mass air flow sensor
(with intake air temperature sensor)
13. Ignition coil (with power transistor)
and spark plug (bank 2)14. Camshaft position sensor (PHASE)
(Bank 2)15. Electric throttle control actuator
16. Fuel injector (bank 2) 17. Knock sensor 18. Fuel injector (bank 1)
19. EVAP canister purge volume con-
trol solenoid valve20. Camshaft position sensor (PHASE)
(Bank 1)21. Engine coolant temperature sensor
22. Ignition coil (with power transistor)
and spark plug (bank 1)23. EVAP service port
PBIB2781E

EC-114
[VQ35DE]
TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
: Vehicle front
1. Mass air flow sensor (With intake air
temperature sensor)2. Electric throttle control actuator 3. Cooling fan motor-2 harness con-
nector
4. Cooling fan motor-1 harness con-
nector5. Cooling fan control module 6. Refrigerant pressure sensor har-
ness connector
7. PCV valve 8. Engine coolant temperature sensor
harness connector9. Fuel dumper
PBIB2787E

TROUBLE DIAGNOSIS
EC-135
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EC
Revision: 2006 January2006 M35/M45
X: Applicable
*1: This item includes 1st trip DTCs.
*2: This mode includes 1st trip freeze frame data or freeze frame data. The items appear on CONSULT-II screen in freeze frame data
mode only if a 1st trip DTC or DTC is detected. For details, refer to EC-59, "
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME
DATA" .
*3: Always “CMPLT” is displayed.
INSPECTION PROCEDURE
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carry out CAN communication.
1. Turn ignition switch OFF.
2. Connect CONSULT-II and CONSULT-II CONVERTER to data
link connector (1), which is located under LH dash panel near
the hood opener handle.
3. Turn ignition switch ON.
ENGINE CONTROL COMPONENT PARTS
OUTPUT
Fuel injector
Power transistor (Ignition timing)
Throttle control motor relay
Throttle control motor
EVAP canister purge volume con-
trol solenoid valve
FPCM
Air conditioner relay
Fuel pump relay
Cooling fan relay
Air fuel ratio (A/F) sensor 1 heater*3
Heated oxygen sensor 2 heater*3
EVAP canister vent control valve
Intake valve timing control solenoid
valve
Alternator
Calculated load value
ItemDIAGNOSTIC TEST MODE
WORK
SUP-
PORTSELF-DIAGNOS-
TIC RESULTS
DATA
MONI-
TORDATA
MONI-
TOR
(SPEC)ACTIVE
TESTDTC & SRT
CONFIRMATION
DTC*1FREEZE
FRAME
DATA*2SRT
STATUSDTC
WORK
SUP-
PORT
PBIB2712E

EC-144
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TROUBLE DIAGNOSIS
Revision: 2006 January2006 M35/M45
*: Leaving cooling fan OFF with CONSULT-II while engine is running may cause the engine to overheat.
DTC & SRT CONFIRMATION MODE
SRT STATUS Mode
For details, refer to EC-60, "SYSTEM READINESS TEST (SRT) CODE" .
SRT WORK SUPPORT Mode
This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.
DTC WORK SUPPORT Mode
*: DTC P1442 and P1456 does not apply to Y50 models but appears in DTC Work Support Mode screens. FA N D U T Y C O N -
TROL*
Ignition switch: ON
Change duty ratio using CON-
SULT-II.Cooling fan speed changes.
Harness and connectors
Cooling fan motor
Cooling fan relay
Cooling fan control module
IPDM E/R
ALTERNATOR
DUTY
Engine: Idle
Change duty ratio using CON-
SULT-II.Battery voltage changes.
Harness and connectors
IPDM E/R
Alternator TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
Test mode Test item Corresponding DTC No. Reference page
EVAPORATIVE SYSTEMEVP SML LEAK P0442/P1442*P0442EC-403
P0455EC-458
EVP V/S LEAK P0456/P1456* P0456EC-466
PURG VOL CN/V P1444 P0443EC-412
PURG FLOW P0441 P0441EC-398
A/F SEN1A/F SEN1 (B1) P1278/P1279 P0133EC-274A/F SEN1 (B1) P1276 P0130EC-246
A/F SEN1 (B2) P1288/P1289 P0153EC-274
A/F SEN1 (B2) P1286 P0150EC-246
HO2S2HO2S2 (B1) P1146 P0138EC-297
HO2S2 (B1) P1147 P0137EC-286
HO2S2 (B1) P0139 P0139EC-310
HO2S2 (B2) P1166 P0158EC-297
HO2S2 (B2) P1167 P0157EC-286
HO2S2 (B2) P0159 P0159EC-310

EC-226
[VQ35DE]
DTC P0117, P0118 ECT SENSOR
Revision: 2006 January2006 M35/M45
DTC P0117, P0118 ECT SENSORPFP:22630
Component DescriptionNBS004VC
The engine coolant temperature sensor is used to detect the engine
coolant temperature. The sensor modifies a voltage signal from the
ECM. The modified signal returns to the ECM as the engine coolant
temperature input. The sensor uses a thermistor which is sensitive to
the change in temperature. The electrical resistance of the ther-
mistor decreases as temperature increases.

*: These data are reference values and are measured between ECM terminal 73
(Engine coolant temperature sensor) and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
On Board Diagnosis LogicNBS004VD
These self-diagnoses have the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, the ECM enters fail-safe mode and the MIL lights up.
SEF594K
Engine coolant temperature
C (F)Voltage* V Resistance k
–10 (14) 4.4 7.0 - 11.4
20 (68) 3.5 2.1 - 2.9
50 (122) 2.2 0.68 - 1.00
90 (194) 0.9 0.236 - 0.260
SEF012P
DTC No.Trouble Diagnosis
NameDTC Detecting Condition Possible Cause
P0117
0117Engine coolant tem-
perature sensor cir-
cuit low inputAn excessively low voltage from the sensor is
sent to ECM.
Harness or connectors
(The sensor circuit is open or shorted.)
Engine coolant temperature sensor
P0118
0118Engine coolant tem-
perature sensor cir-
cuit high inputAn excessively high voltage from the sensor is
sent to ECM.
Detected items Engine operating condition in fail-safe mode
Engine coolant temper-
ature sensor circuitEngine 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.
ConditionEngine coolant temperature decided
(CONSULT-II display)
Just as ignition switch is turned ON or START 40
C (104F)
More than approx. 4 minutes after ignition ON or START 80
C (176F)
Except as shown above40 - 80
C (104 - 176F)
(Depends on the time)
When the fail-safe system for engine coolant temperature sensor is activated, the cooling fan operates
while engine is running.

DTC P0506 ISC SYSTEM
EC-483
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Revision: 2006 January2006 M35/M45
DTC P0506 ISC SYSTEMPFP:23781
DescriptionNBS0051T
NOTE:
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let
into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is
varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects
the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value
memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions,
such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan
operation, etc.).
On Board Diagnosis LogicNBS0051U
DTC Confirmation ProcedureNBS0051V
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait
at least 10 seconds before conducting the next test.
If the target idle speed is out of the specified value, perform EC-96, "Idle Air Volume Learning" ,
before conducting DTC Confirmation Procedure. For the target idle speed, refer to the EC-724,
"SERVICE DATA AND SPECIFICATIONS (SDS)" .
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.
Always perform the test at a temperature above 10C (14F).
WITH CONSULT-II
1. Open engine hood.
2. Start engine and warm it up to normal operating temperature.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON again and select “DATA MONITOR”
mode with CONSULT-II.
5. Start engine and run it for at least 1 minute at idle speed.
6. If 1st trip DTC is detected, go to EC-484, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0506
0506Idle speed control sys-
tem RPM lower than
expectedThe idle speed is less than the target idle
speed by 100 rpm or more.
Electric throttle control actuator
Intake air leak
SEF174Y