engine overheat INFINITI FX35 2005 Service Manual

ATC-96
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
TROUBLE DIAGNOSIS FOR UNUSUAL PRESSURE
Whenever system’s high and/or low side pressure(s) is/are unusual, diagnose using a manifold gauge. The
marker above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the
standard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air tempera-
ture-to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too high. Pressure is reduced soon
after water is splashed on
condenser. Excessive refrigerant charge
in refrigeration cycle. Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is
insufficient. Insufficient condenser cooling
performance.
↓
1. Condenser fins are clogged.
2. Improper fan rotation of cooling fan.

Clean condenser.

Check and repair cooling fan
as necessary.

Low-pressure pipe is not
cold.

When compressor is
stopped high-pressure
value quickly drops by
approximately 196 kPa (2
kg/cm
2 , 28 psi). It then
decreases gradually there-
after. Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure
decreases too slowly.)
↓
Air in refrigeration cycle. Evacuate repeatedly and
recharge system.
Engine tends to overheat. Engine cooling systems mal-
function. Check and repair each engine
cooling system.

An area of the low-pres-
sure pipe is colder than
areas near the evaporator
outlet.

Plates are sometimes cov-
ered with frost.

Excessive liquid refrigerant
on low-pressure side.

Excessive refrigerant dis-
charge flow.

Expansion valve is open a
little compared with the
specification.
↓
Improper expansion valve
adjustment. Replace expansion valve.
AC359A
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too high and
low-pressure side is too low.
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot. High-pressure tube or parts
located between compressor
and condenser are clogged or
crushed.

Check and repair or replace
malfunctioning parts.

Check lubricant for contami-
nation.
AC360A

CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
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SECTION CO
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CO
Revision: 2005 July 2005 FX
ENGINE COOLING SYSTEM
VQ35DE
PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 3
Precautions for Liquid Gasket ............................. ..... 3
REMOVAL OF LIQUID GASKET SEALING ..... ..... 3
LIQUID GASKET APPLICATION PROCEDURE ..... 3
PREPARATION ...................................................... ..... 5
Special Service Tools .......................................... ..... 5
Commercial Service Tools ................................... ..... 6
OVERHEATING CAUSE ANALYSIS ..................... ..... 7
Troubleshooting Chart ......................................... ..... 7
COOLING SYSTEM ............................................... ..... 9
Cooling Circuit ..................................................... ..... 9
System Chart ...................................................... ... 10
ENGINE COOLANT ............................................... ....11
Inspection ............................................................ .... 11
LEVEL CHECK ................................................ .... 11
LEAK CHECK .................................................. .... 11
Changing Engine Coolant ................................... .... 11
DRAINING ENGINE COOLANT ...................... .... 11
REFILLING ENGINE COOLANT ..................... ... 12
FLUSHING COOLING SYSTEM ...................... ... 13
RADIATOR ............................................................. ... 14
Components ........................................................ ... 14
Removal and Installation ..................................... ... 14
REMOVAL ........................................................ ... 14
INSTALLATION ................................................ ... 15
INSPECTION AFTER INSTALLATION ............ ... 15
Checking Radiator Cap ....................................... ... 15
Checking Radiator ............................................... ... 16
RADIATOR (ALUMINUM TYPE) ........................... ... 17
Components ........................................................ ... 17
Disassembly and Assembly ................................ ... 17
PREPARATION ................................................ ... 17
DISASSEMBLY ................................................ ... 17
ASSEMBLY ...................................................... ... 18
INSPECTION ................................................... ... 20 COOLING FAN .......................................................
... 21
Components ........................................................ ... 21
Removal and Installation ..................................... ... 21
REMOVAL ........................................................ ... 21
INSTALLATION ................................................ ... 21
INSPECTION AFTER INSTALLATION ............. ... 21
Disassembly and Assembly ................................. ... 21
DISASSEMBLY ................................................ ... 21
INSPECTION AFTER DISASSEMBLY ............. ... 21
ASSEMBLY ...................................................... ... 21
WATER PUMP ....................................................... ... 22
Components ........................................................ ... 22
Removal and Installation ..................................... ... 22
REMOVAL ........................................................ ... 22
INSPECTION AFTER REMOVAL .................... ... 24
INSTALLATION ................................................ ... 24
INSPECTION AFTER INSTALLATION ............. ... 25
WATER INLET AND THERMOSTAT ASSEMBLY . ... 26
Components ........................................................ ... 26
Removal and Installation ..................................... ... 26
REMOVAL ........................................................ ... 26
INSPECTION AFTER REMOVAL .................... ... 27
INSTALLATION ................................................ ... 27
INSPECTION AFTER INSTALLATION ............. ... 27
WATER OUTLET AND WATER PIPING ................ ... 28
Components ........................................................ ... 28
Removal and Installation ..................................... ... 28
REMOVAL ........................................................ ... 28
INSTALLATION ................................................ ... 29
INSPECTION AFTER INSTALLATION ............. ... 29
SERVICE DATA AND SPECIFICATIONS (SDS) ... ... 30
Standard and Limit ............................................... ... 30
ENGINE COOLANT CAPACITY (APPROXI-
MATE) ............................................................... ... 30
RADIATOR ....................................................... ... 30
THERMOSTAT ................................................. ... 30

CO-2Revision: 2005 July 2005 FX
VK45DE
PRECAUTIONS ......................................................... 31
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .............................................................. ... 31
PREPARATION ...................................................... ... 32
Special Service Tools .......................................... ... 32
Commercial Service Tools ................................... ... 32
OVERHEATING CAUSE ANALYSIS ..................... ... 33
Troubleshooting Chart ......................................... ... 33
COOLING SYSTEM ............................................... ... 35
Cooling Circuit ..................................................... ... 35
System Chart ....................................................... ... 36
ENGINE COOLANT ............................................... ... 37
Inspection ............................................................ ... 37
LEVEL CHECK ................................................. ... 37
LEAK CHECK ................................................... ... 37
Changing Engine Coolant .................................... ... 37
DRAINING ENGINE COOLANT ....................... ... 37
REFILLING ENGINE COOLANT ...................... ... 38
FLUSHING COOLING SYSTEM ...................... ... 39
RADIATOR ............................................................. ... 41
Removal and Installation ..................................... ... 41
REMOVAL ........................................................ ... 41
INSTALLATION ................................................. ... 43
INSPECTION AFTER INSTALLATION ............. ... 43
Checking Radiator Cap ....................................... ... 43
Checking Radiator ............................................... ... 44
RADIATOR (ALUMINUM TYPE) ............................ ... 45
Disassembly and Assembly ................................. ... 45
PREPARATION ................................................ ... 45
DISASSEMBLY ................................................ ... 45
ASSEMBLY ...................................................... ... 46
INSPECTION .................................................... ... 48 COOLING FAN .......................................................
... 49
Removal and Installation (Crankshaft Driven Type) ... 49
REMOVAL ......................................................... ... 49
INSPECTION AFTER REMOVAL ..................... ... 49
INSTALLATION ................................................. ... 49
Removal and Installation (Motor Driven Type) ..... ... 50
REMOVAL ......................................................... ... 50
INSTALLATION ................................................. ... 50
Disassembly and Assembly (Motor Driven Type) ... 50 DISASSEMBLY ................................................. ... 50
INSPECTION AFTER DISASSEMBLY ............. ... 50
ASSEMBLY ....................................................... ... 50
WATER PUMP ........................................................ ... 51
Removal and Installation ...................................... ... 51
REMOVAL ......................................................... ... 51
INSPECTION AFTER REMOVAL ..................... ... 52
INSTALLATION ................................................. ... 52
INSPECTION AFTER INSTALLATION ............. ... 52
THERMOSTAT AND WATER CONTROL VALVE .. ... 53
Removal and Installation ...................................... ... 53
REMOVAL ......................................................... ... 53
INSPECTION AFTER REMOVAL ..................... ... 54
INSTALLATION ................................................. ... 54
INSPECTION AFTER INSTALLATION ............. ... 55
SERVICE DATA AND SPECIFICATIONS (SDS) ... ... 56
Standard and Limit ............................................... ... 56
ENGINE COOLANT CAPACITY (APPROXI-
MATE) ............................................................... ... 56
RADIATOR ........................................................ ... 56
THERMOSTAT .................................................. ... 56
WATER CONTROL VALVE ............................... ... 56

OVERHEATING CAUSE ANALYSIS CO-7
[VQ35DE]
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OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartABS004UZ
Symptom Check items
Cooling sys-
tem parts
malfunction Poor heat transfer
Water pump malfunction Worn or loose drive belt
—
Thermostat 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

CO-8
[VQ35DE]
OVERHEATING CAUSE ANALYSIS
Revision: 2005 July 2005 FX
Except cool-
ing system
parts mal-
function — Overload on engine
Abusive driving
High 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
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

CO-12
[VQ35DE]
ENGINE COOLANT
Revision: 2005 July 2005 FX
4. Check drained engine coolant for contaminants such as rust, corrosion or discoloration.
If contaminated, flush the engine cooling system. Refer to CO-13, "
FLUSHING COOLING SYSTEM" .
REFILLING ENGINE COOLANT
1. Install reservoir tank if removed, 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-128,
"ASSEMBLY" .
2. Make sure that each hose clamp has been firmly tightened.
3. Remove air relief plug on heater hose.
4. Fill radiator, and reservoir tank if removed, to specified level.

Pour engine coolant through engine coolant filler neck
slowly of less than 2 (2-1/8 US qt, 1-3/4 lmp qt) a minute
to allow air in system to escape.

Use Genuine Nissan Long Life Antifreeze/Coolant or
equivalent mixed with water (distilled or demineralized).
Refer to MA-12, "
RECOMMENDED FLUIDS AND LUBRI-
CANTS" .

When engine coolant overflows air relief hole on heater hose,
install air relief plug with new O-ring.
5. Install radiator cap.
6. Warm up until opening thermostat. Standard for warming-up time is approximately 10 minutes at 3,000 rpm.

Make sure thermostat opening condition by touching radiator hose (lower) to see a flow of warm water.
CAUTION:
Watch water temperature gauge so as not to overheat engine.
7. Stop the engine and cool down to less than approximately 50 °C (122 °F).

Cool down using fan to reduce the time. Radiator drain plug:
: 1.18 N·m (0.12 kg-m, 10 in-lb)
SBIA0445E
Engine coolant capacity
(With reservoir tank at “MAX” level)
: Approximately 8.6 (9-1/8 US qt, 7-5/8 lmp qt)
SMA182B
Reservoir tank engine coolant capacity
(At “MAX” level)
: 0.8 (7/8 US qt, 3/4 lmp qt)
Air relief plug: : 1.19 N·m (0.12 kg-m, 11 in-lb)
SMA412B

OVERHEATING CAUSE ANALYSIS CO-33
[VK45DE]
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OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartABS006JF
Symptom Check items
Cooling sys-
tem parts
malfunction Poor heat transfer
Water pump malfunction Worn or loose drive belt
—
Thermostat 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

CO-34
[VK45DE]
OVERHEATING CAUSE ANALYSIS
Revision: 2005 July 2005 FX
Except cool-
ing system
parts mal-
function — Overload on engine
Abusive driving
High 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
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

ENGINE COOLANT CO-39
[VK45DE]
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When engine coolant overflows air relief hole on heater hose,
install air relief plug.
5. Install radiator cap.
6. Warm up until opening thermostat. Standard for warming-up time is approximately 10 minutes at 3,000 rpm.

Make sure thermostat opening condition by touching radiator hose (lower) to see a flow of warm water.
CAUTION:
Watch water temperature gauge so as not to overheat engine.
7. Stop engine and cool down to less than approximately 50 °C (122 °F).

Cool down using a fan to reduce the time.

If necessary, refill engine coolant up to filler neck of thermostat housing.
8. Refill reservoir tank to “MAX” level line with engine coolant.
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-249,
"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. Reservoir tank engine coolant capacity
(At “MAX” level):
0.8 (7/8 US qt, 3/4 lmp qt)
SMA412B
Radiator drain plug:
: 1.19 N·m (0.12 kg-m, 11 in-lb)
PBIC1530E

EC-5
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EC A
Revision: 2005 July 2005 FX
FUNCTION .............................................................
. 426
Description .......................................................... . 426
On Board Diagnosis Logic .................................. . 426
DTC Confirmation Procedure .............................. . 426
Wiring Diagram ................................................... . 427
Diagnostic Procedure .......................................... . 428
Component Inspection ........................................ . 431
Remove and Installation ...................................... . 431
DTC P1124, P1126 THROTTLE CONTROL MOTOR
RELAY ................................................................... . 432
Component Description ....................................... . 432
CONSULT-II Reference Value in Data Monitor Mode . 432
On Board Diagnosis Logic .................................. . 432
DTC Confirmation Procedure .............................. . 432
Wiring Diagram ................................................... . 434
Diagnostic Procedure .......................................... . 435
DTC P1128 THROTTLE CONTROL MOTOR ....... . 437
Component Description ....................................... . 437
On Board Diagnosis Logic .................................. . 437
DTC Confirmation Procedure .............................. . 437
Wiring Diagram ................................................... . 438
Diagnostic Procedure .......................................... . 439
Component Inspection ........................................ . 440
Removal and Installation ..................................... . 441
DTC P1146, P1166 HO2S2 .................................... . 442
Component Description ....................................... . 442
CONSULT-II Reference Value in Data Monitor Mode . 442
On Board Diagnosis Logic .................................. . 442
DTC Confirmation Procedure .............................. . 443
Overall Function Check ....................................... . 443
Wiring Diagram ................................................... . 445
Diagnostic Procedure .......................................... . 448
Component Inspection ........................................ . 450
Removal and Installation ..................................... . 452
DTC P1147, P1167 HO2S2 .................................... . 453
Component Description ....................................... . 453
CONSULT-II Reference Value in Data Monitor Mode . 453
On Board Diagnosis Logic .................................. . 453
DTC Confirmation Procedure .............................. . 454
Overall Function Check ....................................... . 454
Wiring Diagram ................................................... . 456
Diagnostic Procedure .......................................... . 459
Component Inspection ........................................ . 461
Removal and Installation ..................................... . 463
DTC P1148, P1168 CLOSED LOOP CONTROL ... . 464
On Board Diagnosis Logic .................................. . 464
DTC P1211 TCS CONTROL UNIT ........................ . 465
Description .......................................................... . 465
On Board Diagnosis Logic .................................. . 465
DTC Confirmation Procedure .............................. . 465
Diagnostic Procedure .......................................... . 465
DTC P1212 TCS COMMUNICATION LINE ........... . 466
Description .......................................................... . 466
On Board Diagnosis Logic .................................. . 466
DTC Confirmation Procedure .............................. . 466
Diagnostic Procedure .......................................... . 466 DTC P1217 ENGINE OVER TEMPERATURE .......
.467
Description ........................................................... .467
CONSULT-II Reference Value in Data Monitor Mode .469
On Board Diagnosis Logic ................................... .469
Overall Function Check ....................................... .469
Wiring Diagram .................................................... .471
Diagnostic Procedure .......................................... .473
Main 12 Causes of Overheating .......................... .478
Component Inspection ......................................... .478
DTC P1225 TP SENSOR ....................................... .479
Component Description ....................................... .479
On Board Diagnosis Logic ................................... .479
DTC Confirmation Procedure .............................. .479
Diagnostic Procedure .......................................... .480
Removal and Installation ..................................... .480
DTC P1226 TP SENSOR ....................................... .481
Component Description ....................................... .481
On Board Diagnosis Logic ................................... .481
DTC Confirmation Procedure .............................. .481
Diagnostic Procedure .......................................... .482
Removal and Installation ..................................... .482
DTC P1229 SENSOR POWER SUPPLY ............... .483
On Board Diagnosis Logic ................................... .483
DTC Confirmation Procedure .............................. .483
Wiring Diagram .................................................... .484
Diagnostic Procedure .......................................... .485
DTC P1271, P1281 A/F SENSOR 1 ...................... .488
Component Description ....................................... .488
CONSULT-II Reference Value in Data Monitor Mode .488
On Board Diagnosis Logic ................................... .488
DTC Confirmation Procedure .............................. .488
Wiring Diagram .................................................... .490
Diagnostic Procedure .......................................... .493
Removal and Installation ..................................... .496
DTC P1272, P1282 A/F SENSOR 1 ...................... .497
Component Description ....................................... .497
CONSULT-II Reference Value in Data Monitor Mode .497
On Board Diagnosis Logic ................................... .497
DTC Confirmation Procedure .............................. .497
Wiring Diagram .................................................... .499
Diagnostic Procedure .......................................... .502
Removal and Installation ..................................... .505
DTC P1273, P1283 A/F SENSOR 1 ...................... .506
Component Description ....................................... .506
CONSULT-II Reference Value in Data Monitor Mode .506
On Board Diagnosis Logic ................................... .506
DTC Confirmation Procedure .............................. .506
Wiring Diagram .................................................... .508
Diagnostic Procedure .......................................... .511
Removal and Installation ..................................... .515
DTC P1274, P1284 A/F SENSOR 1 ...................... .516
Component Description ....................................... .516
CONSULT-II Reference Value in Data Monitor Mode .516
On Board Diagnosis Logic ................................... .516