heating INFINITI QX56 2008 Factory Service Manual

BRM-34
< SERVICE INFORMATION >
BODY REPAIR
Precaution in Repairing High Strength Steel
INFOID:0000000001609804
High strength steel is used for body panels in order to reduce vehicle weight.
Accordingly, precautions in repairing automotive bodies made of high strength steel are described below:
High strength steel (hss) used in nissan vehicles
SP130 is the most commonly used HSS.
SP150 HSS is used only on parts that require much more strength.
Read the following precautions when repairing HSS:
1. Additional points to consider • The repair of reinforcements (such as side members) by heat-ing is not recommended since it may weaken the component.
When heating is unavoidable, do not heat HSS parts above
550° C (1,022° F).
Verify heating temperature with a thermometer.
(Crayon-type and other similar type thermometer are appropri-
ate.)
LIIA1061E
Tensile strength Nissan/Infiniti designation Major applicable parts
373 N/mm
2
(38kg/mm2 ,54klb/sq in) SP130• Front inner pillar upper
• Front pillar hinge brace
• Outer front pillar reinforcement
• Other reinforcements
785-981 N/mm
2
(80-100kg/mm2
114-142klb/sq in) SP150
• Outer sill reinforcement
• Main back pillar
PIIA0115E
Revision: March 2010
2008 QX56

CO-1
ENGINE
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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 ..........................................5
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
Removal and Installation ..................................... ....15
ENGINE COOLING FAN ...................................18
Removal and Installation (Crankshaft Driven
Type) .......................................................................
18
Removal and Installation (Motor Driven Type) ........19
WATER PUMP ..................................................20
Removal and Installation .........................................20
THERMOSTAT AND WATER PIPING ..............22
Removal and Installation .........................................22
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... .......................................... ...
24
SERVICE DATA AND SPECIFICATIONS
(SDS) .................................................................
24
Standard and Limit .............................................. ....24
Revision: March 2010 2008 QX56

CO-8
< FUNCTION DIAGNOSIS >
OVERHEATING CAUSE ANALYSIS
OVERHEATING CAUSE ANALYSIS
Troubleshooting ChartINFOID:0000000001538857
SymptomCheck 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 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 —— —
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
Revision: March 2010
2008 QX56

OVERHEATING CAUSE ANALYSISCO-9
< FUNCTION DIAGNOSIS >
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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
Revision: March 2010 2008 QX56

THERMOSTAT AND WATER PIPINGCO-23
< ON-VEHICLE REPAIR >
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3. Remove the engine room cover using power tool.
4. Disconnect the heater hose (heater core side).
5. Remove the heater hose bracket.
6. Disconnect the water cut valve connector.
7. Remove the water cut valve.
INSPECTION AFTER REMOVAL
• Place a thread so that it is caught
in the valve of the thermostat.
Immerse fully in a container filled with water. Heat while stirring.
• The valve opening temperature is the temperature at which the valve opens and falls from the thread.
• Continue heating. Check the full-open lift amount.
• After checking the full-open lift amount, lower the water tempera- ture and check the valve closing temperature.
Standard values:
INSTALLATION
Installation is in the reverse order of removal.
Installation of Thermostat
• Install the thermostat with the whole circumference of each flange
part fit securely inside the rubber ring as shown.
• Install the thermostat with the jiggle valve facing upwards.
Installation of Water Outlet Pipe and Heater Pipe
First apply a neutral detergent to the O- rings, then quickly insert the insertion parts of the water outlet pipe and
heater pipe into the installation holes.
INSPECTION AFTER INSTALLATION
• Check for leaks of the engine coolant. Refer to CO-10, "Inspection".
• Start and warm up the engine. Visually check for leaks of the engine coolant.
SLC252B
Thermostat
Valve opening temperature 80 - 84°C (176 - 183 ° F)
Full-open lift amount More than 10 mm/ 95°C (0.39 in/ 203° F)
Valve closing temperature 77°C (171 °F) or higher
KBIA2502E
Revision: March 2010 2008 QX56

REAR WINDOW DEFOGGER SYSTEMDEF-5
< FUNCTION DIAGNOSIS >
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Component Parts LocationINFOID:0000000001735604
Component DescriptionINFOID:0000000001735605
ALLIA0314ZZ
1. A. Steering column assembly B. BCM M18, M20 (view with instru-
ment panel removed) 2. A/C and AV switch assembly (rear
window defogger switch) M98 3. A. Rear window defogger ground
connector D604
B. Rear window defogger connector
D406
4. IPDM E/R E120, E122, E124 5. Do or mirror (door mirror defogger)
LH D4, RH D107
BCM • Operates the rear window defogger with the operation of rear window defogger switch.
• Performs the timer control of rear window defogger.
Rear window defogger relay • Operates the rear window defogger and the door mirror defogger with the control signal from
BCM.
A/C and AV switch assembly
(rear window defogger switch) • The rear window defogger switch is turned ON.
• Turns the indicator lamp ON when detecting the operation of rear window defogger.
Rear window defogger • Heats the heating wire with the power supply from the rear window defogger relay to prevent
the rear window from fogging up.
Door mirror defogger • Heats the heating wire with the power supply from the heated mirror relay to prevent the door
mirror from fogging up.
Revision: March 2010 2008 QX56

DEF-10
< COMPONENT DIAGNOSIS >
REAR WINDOW DEFOGGER POWER SUPPLY AND GROUND CIRCUIT
REAR WINDOW DEFOGGER POWER SUPPLY AND GROUND CIRCUIT
DescriptionINFOID:0000000001735615
Heats the heating wire with the power supply from the rear window defogger relay to prevent the rear window
from fogging up.
Component Function CheckINFOID:0000000001735616
1. CHECK REAR WINDOW DEFOGGER
Check that the heating wire of rear window defogger is heated when turning the rear window defogger switch
ON.
Is the inspection result normal?
YES >> Rear window defogger is OK.
NO >> Refer to DEF-10, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001735617
1. CHECK POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check voltage between rear window defogger connector and ground.
Is the inspection result normal?
YES >> GO TO 2
NO >> GO TO 3
2. CHECK GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect rear window defogger.
3. Check continuity between rear window defogger connector and ground.
Is the inspection result normal?
YES >> GO TO 4
NO >> Repair or replace harness.
3. CHECK HARNESS CONTINUITY
Te r m i n a l s Condition of rear window
defogger switch Voltage (V)
(Approx.)
(+)
(–)
Rear window
defogger
connector Te r m i n a l
D406 1 Ground ON Battery voltage
OFF 0
ALLIA0177ZZ
Rear window defogger connector Terminal
GroundContinuity
D604 2 Yes
ALLIA0178ZZ
Revision: March 2010 2008 QX56

DEF-12
< COMPONENT DIAGNOSIS >
DOOR MIRROR DEFOGGER LH
DOOR MIRROR DEFOGGER LH
DescriptionINFOID:0000000001735623
Heats the heating wire with the power supply from the rear window defogger relay to prevent the door mirror
from fogging up.
Component Function CheckINFOID:0000000001735624
1. CHECK DOOR MIRROR DEFOGGER LH
Check that heating wire of door mirror defogger LH is heated when turning the rear window defogger switch
ON.
Is the inspection result normal?
YES >> Door mirror defogger is OK.
NO >> Refer to DEF-12, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001735625
1. CHECK POWER SUPPLY
Check if the following fuse in the IPDM E/R is blown.
Is the inspection result normal?
YES >> GO TO 2
NO >> If fuse is blown, be sure to eliminate cause of malfunction before installing new fuse.
2. CHECK DOOR MIRROR DE FOGGER POWER SUPPLY CIRCUIT
Check voltage between IPDM E/R connector and ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Replace IPDM E/R. Refer to PCS-34, "
Removal and Installation of IPDM E/R".
3. CHECK DOOR MIRROR DEFOGGER POWER SUPPLY CIRCUIT 2
1. Turn ignition switch OFF.
2. Disconnect door mirror LH.
3. Turn ignition switch ON.
4. Check voltage between door mirror LH connector and ground.
Is the inspection result normal?
YES >> GO TO 4
COMPONENT PARTS AMPEREFUSE NO.
IPDM E/R 15A43
ConnectorTe r m i n a l
ConditionVoltage (V)
(Approx.)
(+) (-)
E120 23 Ground Rear window defogger
switch ON
Battery voltage
Rear window defogger
switch OFF 0
LIIA2049E
ConnectorTe r m i n a l
ConditionVoltage (V)
(Approx.)
(+) (-)
D4 10 Ground Rear window defogger
switch ON
Battery voltage
Rear window defogger
switch OFF 0
LIIA1456E
Revision: March 2010
2008 QX56

DEF-14
< COMPONENT DIAGNOSIS >
DOOR MIRROR DEFOGGER RH
DOOR MIRROR DEFOGGER RH
DescriptionINFOID:0000000001735631
Heats the heating wire with the power supply from the rear window defogger relay to prevent the door mirror
from fogging up.
Component Function CheckINFOID:0000000001735632
1.CHECK DOOR MIRROR DEFOGGER RH
Check that the heating wire of door mirror defogger RH is heated when turning the rear window defogger
switch ON.
Is the inspection result normal?
YES >> Door mirror defogger RH is OK.
NO >> Refer to DEF-14, "
Diagnosis Procedure".
Diagnosis ProcedureINFOID:0000000001735633
1. CHECK POWER SUPPLY
Check if the following fuse in the IPDM E/R is blown.
Is the inspection result normal?
YES >> GO TO 2
NO >> If fuse is blown, be sure to eliminate cause of malfunction before installing new fuse.
2. CHECK DOOR MIRROR DE FOGGER POWER SUPPLY CIRCUIT
Check voltage between IPDM E/R connector and ground.
Is the inspection result normal?
YES >> GO TO 3
NO >> Replace IPDM E/R. Refer to PCS-34, "
Removal and Installation of IPDM E/R".
3. CHECK DOOR MIRROR DEFOGGER POWER SUPPLY CIRCUIT 2
1. Turn ignition switch OFF.
2. Disconnect door mirror RH.
3. Turn ignition switch ON.
4. Check voltage between door mirror RH connector and ground.
Is the inspection result normal?
YES >> GO TO 4
COMPONENT PARTS AMPEREFUSE NO.
IPDM E/R 15A43
ConnectorTe r m i n a l
ConditionVoltage (V)
(Approx.)
(+) (-)
E120 23 Ground Rear window defogger
switch ON
Battery voltage
Rear window defogger
switch OFF 0
LIIA2049E
ConnectorTe r m i n a l
ConditionVoltage (V)
(Approx.)
(+) (-)
D107 10 Ground Rear window defogger
switch ON
Battery voltage
Rear window defogger
switch OFF 0
LIIA1456E
Revision: March 2010
2008 QX56

EC-5
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EC A
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P1148, P1168 CLOSED LOOP CONTROL ... ..303
On Board Diagnosis Logic .................................. ..303
P1211 TCS CONTROL UNIT ...........................304
Description .......................................................... ..304
On Board Diagnosis Logic ....................................304
DTC Confirmation Procedure ................................304
Diagnosis Procedure .............................................304
P1212 TCS COMMUNICATION LINE ..............305
Description .......................................................... ..305
On Board Diagnosis Logic ....................................305
DTC Confirmation Procedure ................................305
Diagnosis Procedure .............................................305
P1217 ENGINE OVER TEMPERATURE .........306
On Board Diagnosis Logic .................................. ..306
Overall Function Check .........................................306
Diagnosis Procedure .............................................307
Main 13 Causes of Overheating ............................308
P1225 TP SENSOR ..........................................310
Component Description ....................................... ..310
On Board Diagnosis Logic ....................................310
DTC Confirmation Procedure ................................310
Diagnosis Procedure .............................................310
P1226 TP SENSOR ..........................................312
Component Description ....................................... ..312
On Board Diagnosis Logic ....................................312
DTC Confirmation Procedure ................................312
Diagnosis Procedure .............................................312
P1421 COLD START CONTROL .....................314
Description .......................................................... ..314
On Board Diagnosis Logic ....................................314
DTC Confirmation Procedure ................................314
Diagnosis Procedure .............................................314
P1550 BATTERY CURRENT SENSOR ...........316
Component Description ....................................... ..316
On Board Diagnosis Logic ....................................316
DTC Confirmation Procedure ................................316
Diagnosis Procedure .............................................316
Component Inspection ..........................................318
P1551, P1552 BATTERY CURRENT SEN-
SOR ..................................................................
320
Component Description ....................................... ..320
On Board Diagnosis Logic ....................................320
DTC Confirmation Procedure ................................320
Diagnosis Procedure .............................................320
Component Inspection ..........................................322
P1553 BATTERY CURRENT SENSOR ...........324
Component Description ....................................... ..324
On Board Diagnosis Logic ....................................324
DTC Confirmation Procedure ................................324
Diagnosis Procedure .............................................324
Component Inspection ..........................................326
P1554 BATTERY CURRENT SENSOR ..........328
Component Description ....................................... ..328
On Board Diagnosis Logic .....................................328
Overall Function Check .........................................328
Diagnosis Procedure .............................................329
Component Inspection ...........................................330
P1564 ICC STEERING SWITCH .....................332
Component Description .........................................332
On Board Diagnosis Logic .....................................332
DTC Confirmation Procedure ................................332
Diagnosis Procedure .............................................332
Component Inspection ...........................................335
P1564 ASCD STEERING SWITCH .................336
Component Description .........................................336
On Board Diagnosis Logic .....................................336
DTC Confirmation Procedure ................................336
Diagnosis Procedure .............................................336
Component Inspection ...........................................338
P1568 ICC FUNCTION ....................................340
On Board Diagnosis Logic .....................................340
DTC Confirmation Procedure ................................340
Diagnosis Procedure .............................................340
P1572 ICC BRAKE SWITCH ..........................341
Component Description .........................................341
On Board Diagnosis Logic .....................................341
DTC Confirmation Procedure ................................341
Diagnosis Procedure .............................................342
Component Inspection ...........................................346
P1572 ASCD BRAKE SWITCH ......................347
Component Description .........................................347
On Board Diagnosis Logic .....................................347
DTC Confirmation Procedure ................................347
Diagnosis Procedure .............................................348
Component Inspection ...........................................351
P1574 ICC VEHICLE SPEED SENSOR .........352
Component Description .........................................352
On Board Diagnosis Logic .....................................352
DTC Confirmation Procedure ................................352
Diagnosis Procedure .............................................352
P1574 ASCD VEHICLE SPEED SENSOR .....354
Component Description .........................................354
On Board Diagnosis Logic .....................................354
DTC Confirmation Procedure ................................354
Diagnosis Procedure .............................................354
P1805 BRAKE SWITCH .................................356
Description .............................................................356
On Board Diagnosis Logic .....................................356
DTC Confirmation Procedure ................................356
Diagnosis Procedure .............................................356
Component Inspection ...........................................358
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY ....................................................
359
Revision: March 2010 2008 QX56