2008 INFINITI FX35 heating

CO-8
< SERVICE INFORMATION >[VQ35DE]
OVERHEATING CAUSE ANALYSIS
Except cool-
ing system
parts mal-
function— Overload on engine
Abusive driving
High engine rpm under no
load
Driving in low gear for ex-
tended time
Driving at extremely high
speed
Powertrain sy stem malfunc-
tion
—
Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flow Blocked bumper —
—
Blocked radiator grille
Installed 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-34
< SERVICE INFORMATION >[VK45DE]
OVERHEATING CAUSE ANALYSIS
OVERHEATING CAUSE ANALYSIS
Troubleshooting ChartINFOID:0000000001325866
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 pa-
per 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 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
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OVERHEATING CAUSE ANALYSISCO-35
< SERVICE INFORMATION > [VK45DE]
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Except cool-
ing system
parts mal-
function — Overload on engine
Abusive driving
High engine rpm under no
load
Driving in low gear for ex-
tended time
Driving at extremely high
speed
Powertrain system malfunc-
tion
—
Installed improper size
wheels and tires
Dragging brakes
Improper ignition timing
Blocked or restricted air
flow Blocked bumper —
—
Blocked radiator grille
Installed car brassiere
Mud contamination or paper
clogging
Blocked radiator —
Blocked condenser Blocked air flow
Installed large fog lamp
Symptom Check items
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
3A893A873A873A8F3A773A9D3AAF3A8A3A8C3A863A9D3AAF3A8B3A8C

THERMOSTAT AND WATER CONTROL VALVECO-53
< SERVICE INFORMATION > [VK45DE]
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 Refer to
GI-8, "Component" for symbols in the figure.
Removal and InstallationINFOID:0000000001325885
REMOVAL
1. Drain engine coolant from drain plugs on radiat or and both side of cylinder block. Refer to CO-37, "Chang-
ing Engine Coolant" and EM-242, "Disassembly and Assembly".
CAUTION:
 Perform this step when engine is cold.
 Do not spill engine coolant on drive belts.
2. Remove engine cover with power tool. Refer to EM-169, "
Component".
3. Remove air duct (inlet). Refer to EM-173, "
Component".
4. Disconnect water suction hose from water inlet.
5. Remove water inlet and thermostat. CAUTION:
Do not disassemble thermostat.
6. Remove intake manifolds (upper and lower). Refer to EM-175, "
Component".
7. Disconnect radiator hose (upper) and wa ter hoses from thermostat housing.
8. Disconnect heater hoses from water outlet and heater pipe.
9. Remove thermostat housing, water outlet pipe, water connector, water control valve, water outlet and heater pipe.
CAUTION:
Do not disassemble water control valve.
INSPECTION AFTER REMOVAL
 Make sure that valves both in thermostat and water c ontrol valve are completely closing at normal tempera-
ture.
 Place a thread so that it is caught in the valves of the thermostat
and water control valve. Immerse fully in a container filled with
water. Heat while stirring. (The example in the figure shows ther-
mostat.)
 The valve opening temperature is the temperature at which the valve opens and falls from the thread.
 Continue heating. Check the maximum valve lift. NOTE:
The maximum valve lift standard temperature for water control
valve is the reference value.
 After checking the maximum valve lift, lower the water tempera-
ture and check the valve closing temperature.
Standard values:
 If the malfunctioning condition, when closing valve at nor mal temperature, or measured values are out of the
standard, replace thermostat and/or water control valve.
INSTALLATION
Note the following, and install in the reverse order of removal.
CAUTION:
Be careful not to spill engine coolant over en gine room. Use rag to absorb engine coolant.
Thermostat and Water Control Valve
D. To heater core E. To cylinder head (left bank) F. To cylinder head (right bank)
G. To intake manifold adapter
SLC252B
Thermostat Water control valve
Valve opening temperature 80 - 84 °C (176 - 183 °F) 93.5 - 96.5 °C (200 - 206 °F)
Maximum valve lift More than 10 mm/95
°C
(0.39 in/203 °F) More than 8 mm/108
°C
(0.315 in/226 °F)
Valve closing temperature 77 °C (171 °F) 90 °C (194 °F)
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
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EC-6
Diagnosis Procedure .............................................420
DTC P0605 ECM ..............................................422
Component Description ....................................... ..422
On Board Diagnosis Logic .....................................422
DTC Confirmation Procedure ................................422
Diagnosis Procedure .............................................423
DTC P0643 SENSOR POWER SUPPLY ........424
On Board Diagnosis Logic ................................... ..424
DTC Confirmation Procedure ................................424
Wiring Diagram ......................................................425
Diagnosis Procedure .............................................426
DTC P0850 PNP SWITCH ...............................429
Component Description ....................................... ..429
CONSULT-III Reference Value in Data Monitor
Mode .................................................................... ..
429
On Board Diagnosis Logic .....................................429
DTC Confirmation Procedure ................................429
Overall Function Check .........................................430
Wiring Diagram ......................................................431
Diagnosis Procedure .............................................432
DTC P1148, P1168 CLOSED LOOP CON-
TROL ................................................................
434
On Board Diagnosis Logic ................................... ..434
DTC P1211 TCS CONTROL UNIT ..................435
Description ........................................................... ..435
On Board Diagnosis Logic .....................................435
DTC Confirmation Procedure ................................435
Diagnosis Procedure .............................................435
DTC P1212 TCS COMMUNICATION LINE .....436
Description ........................................................... ..436
On Board Diagnosis Logic .....................................436
DTC Confirmation Procedure ................................436
Diagnosis Procedure .............................................436
DTC P1217 ENGINE OVER TEMPERATURE .437
Description ........................................................... ..437
CONSULT-III Reference Value in Data Monitor
Mode .................................................................... ..
438
On Board Diagnosis Logic .....................................438
Overall Function Check .........................................439
Wiring Diagram ......................................................440
Diagnosis Procedure .............................................441
Main 12 Causes of Overheating ............................445
Component Inspection ...........................................446
DTC P1225 TP SENSOR .................................447
Component Description ....................................... ..447
On Board Diagnosis Logic .....................................447
DTC Confirmation Procedure ................................447
Diagnosis Procedure .............................................447
Removal and Installation .......................................448
DTC P1226 TP SENSOR .................................449
Component Description ....................................... ..449
On Board Diagnosis Logic .....................................449
DTC Confirmation Procedure ............................... .449
Diagnosis Procedure .............................................449
Removal and Installation .......................................450
DTC P1421 COLD START CONTROL ............451
Description ........................................................... .451
On Board Diagnosis Logic ....................................451
DTC Confirmation Procedure ................................451
Diagnosis Procedure .............................................451
DTC P1564 ICC STEERING SWITCH ..............453
Component Description ....................................... .453
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................
453
On Board Diagnosis Logic ....................................453
DTC Confirmation Procedure ................................453
Wiring Diagram .....................................................455
Diagnosis Procedure .............................................456
Component Inspection ..........................................458
DTC P1564 ASCD STEERING SWITCH ..........459
Component Description ....................................... .459
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................
459
On Board Diagnosis Logic ....................................459
DTC Confirmation Procedure ................................459
Wiring Diagram .....................................................460
Diagnosis Procedure .............................................461
Component Inspection ..........................................463
DTC P1568 ICC FUNCTION .............................464
On Board Diagnosis Logic ................................... .464
DTC Confirmation Procedure ................................464
Diagnosis Procedure .............................................464
DTC P1572 ICC BRAKE SWITCH ...................465
Component Description ....................................... .465
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................
465
On Board Diagnosis Logic ....................................465
DTC Confirmation Procedure ................................465
Wiring Diagram .....................................................467
Diagnosis Procedure .............................................468
Component Inspection ..........................................472
DTC P1572 ASCD BRAKE SWITCH ...............474
Component Description ....................................... .474
CONSULT-III Reference Value in Data Monitor
Mode .....................................................................
474
On Board Diagnosis Logic ....................................474
DTC Confirmation Procedure ................................474
Wiring Diagram .....................................................476
Diagnosis Procedure .............................................477
Component Inspection ..........................................480
DTC P1574 ICC VEHICLE SPEED SENSOR ..481
Component Description ........................................481
On Board Diagnosis Logic ....................................481
DTC Confirmation Procedure ................................481
Diagnosis Procedure .............................................481
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EC-13
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DTC P0462, P0463 FUEL LEVEL SENSOR .. ..990
Component Description ....................................... ..990
On Board Diagnosis Logic ....................................990
DTC Confirmation Procedure ................................990
Diagnosis Procedure .............................................990
Removal and Installation .......................................991
DTC P0500 VSS ...............................................992
Description .......................................................... ..992
On Board Diagnosis Logic ....................................992
DTC Confirmation Procedure ................................992
Overall Function Check .........................................993
Diagnosis Procedure .............................................993
DTC P0506 ISC SYSTEM ................................994
Description .......................................................... ..994
On Board Diagnosis Logic ....................................994
DTC Confirmation Procedure ................................994
Diagnosis Procedure .............................................994
DTC P0507 ISC SYSTEM ................................996
Description .......................................................... ..996
On Board Diagnosis Logic ....................................996
DTC Confirmation Procedure ................................996
Diagnosis Procedure .............................................996
DTC P0550 PSP SENSOR ............................. ..998
Component Description ....................................... ..998
CONSULT-III Reference Value in Data Monitor
Mode ................................................................... ..
998
On Board Diagnosis Logic ....................................998
DTC Confirmation Procedure ................................998
Wiring Diagram .....................................................999
Diagnosis Procedure ...........................................1000
Component Inspection ........................................1002
Removal and Installation .....................................1002
DTC P0603 ECM POWER SUPPLY ..............1003
Component Description .......................................1003
On Board Diagnosis Logic ..................................1003
DTC Confirmation Procedure ..............................1003
Wiring Diagram ...................................................1004
Diagnosis Procedure ...........................................1005
DTC P0605 ECM ............................................1007
Component Description .......................................1007
On Board Diagnosis Logic ..................................1007
DTC Confirmation Procedure ..............................1007
Diagnosis Procedure ...........................................1008
DTC P0643 SENSOR POWER SUPPLY .......1009
On Board Diagnosis Logic ..................................1009
DTC Confirmation Procedure ..............................1009
Wiring Diagram ...................................................1010
Diagnosis Procedure ...........................................1011
DTC P0850 PNP SWITCH ..............................1014
Component Description .......................................1014
CONSULT-III Reference Value in Data Monitor
Mode ...................................................................
1014
On Board Diagnosis Logic ..................................1014
DTC Confirmation Procedure ..............................1014
Overall Function Check .......................................1015
Wiring Diagram ....................................................1016
Diagnosis Procedure ...........................................1017
DTC P1140, P1145 IVT CONTROL POSITION
SENSOR .........................................................
1019
Component Description .......................................1019
CONSULT-III Reference Value in Data Monitor
Mode ....................................................................
1019
On Board Diagnosis Logic ...................................1019
DTC Confirmation Procedure ..............................1019
Wiring Diagram ....................................................1020
Diagnosis Procedure ...........................................1023
Component Inspection .........................................1025
Removal and Installation .....................................1026
DTC P1148, P1168 CLOSED LOOP CON-
TROL ..............................................................
1027
On Board Diagnosis Logic ...................................1027
DTC P1211 TCS CONTROL UNIT .................1028
Description ...........................................................1028
On Board Diagnosis Logic ...................................1028
DTC Confirmation Procedure ..............................1028
Diagnosis Procedure ...........................................1028
DTC P1212 TCS COMMUNICATION LINE ...1029
Description ...........................................................1029
On Board Diagnosis Logic ...................................1029
DTC Confirmation Procedure ..............................1029
Diagnosis Procedure ...........................................1029
DTC P1217 ENGINE OVER TEMPERATURE 1030
Description ...........................................................1030
CONSULT-III Reference Value in Data Monitor
Mode ....................................................................
1031
On Board Diagnosis Logic ...................................1031
Overall Function Check .......................................1032
Wiring Diagram ....................................................1034
Diagnosis Procedure ...........................................1035
Main 13 Causes of Overheating ..........................1039
Component Inspection .........................................1040
DTC P1225 TP SENSOR ...............................1041
Component Description .......................................1041
On Board Diagnosis Logic ...................................1041
DTC Confirmation Procedure ..............................1041
Diagnosis Procedure ...........................................1041
Removal and Installation .....................................1042
DTC P1226 TP SENSOR ...............................1043
Component Description .......................................1043
On Board Diagnosis Logic ...................................1043
DTC Confirmation Procedure ..............................1043
Diagnosis Procedure ...........................................1043
Removal and Installation .....................................1044
DTC P1421 COLD START CONTROL ..........1045
Description ...........................................................1045
On Board Diagnosis Logic ...................................1045
3AA93ABC3ACD3AC03ACA3AC03AC63AC53A913A773A893A873A873A8E3A773A983AC73AC93AC03AC3
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DTC P0181 FTT SENSOREC-297
< SERVICE INFORMATION > [VQ35DE]
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5.CHECK FUEL TANK TEMPERATURE SENSOR GROUND CIRCUIT FOR OPEN AND SHORT
1. Turn ignition switch OFF.
2. Disconnect “unified meter and A/C amp.” harness connector.
3. Check harness continuity between “fuel level sensor unit and fuel pump” terminal 5 and “unified meter and
A/C amp.” terminal 36. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors B1, M11
 Harness for open or short between “fuel level sensor unit and fuel pump” and “unified meter and A/C amp.”
>> Repair open circuit or short to ground or short to power in harness or connector.
7.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-297, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Replace fuel level sensor unit.
8.CHECK INTERMITTENT INCIDENT
Refer to EC-139
.
>> INSPECTION END
Component InspectionINFOID:0000000001326114
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 4 and 5 by heating with hot water as shown in the fig-
ure.
If NG, replace fuel level sensor unit.
Removal and InstallationINFOID:0000000001326115
FUEL TANK TEMPERATURE SENSOR
Refer to FL-4.
Continuity should exist.
Temperature
°C ( °F) Resistance k Ω
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
PBIB0931E
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DTC P0182, P0183 FTT SENSOREC-301
< SERVICE INFORMATION > [VQ35DE]
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3. Check harness continuity between “fuel level sensor
unit and fuel pump” terminal 5 and “unified meter and
A/C amp.” terminal 36. Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 7.
NG >> GO TO 6.
6.DETECT MALFUNCTIONING PART
Check the following.
 Harness connectors B1, M11
 Harness for open or short between “fuel level sensor unit and fuel pump” and “unified meter and A/C amp.”
>> Repair open circuit or short to ground or short to power in harness or connector.
7.CHECK FUEL TANK TEMPERATURE SENSOR
Refer to EC-301, "
Component Inspection".
OK or NG
OK >> GO TO 8.
NG >> Replace fuel level sensor unit.
8.CHECK INTERMITTENT INCIDENT
Refer to EC-139
.
>> INSPECTION END
Component InspectionINFOID:0000000001326121
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump”
terminals 4 and 5 by heating with hot water as shown in the fig-
ure.
If NG, replace fuel level sensor unit.
Removal and InstallationINFOID:0000000001326122
FUEL TANK TEMPERATURE SENSOR
Refer to FL-4.
Continuity should exist.
Temperature
°C ( °F) Resistance k Ω
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
PBIB0931E
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