coolant INFINITI QX56 2008 Factory Service Manual

BLOWER MOTOR CONTROL SYSTEMHAC-49
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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BLOWER MOTOR CONTROL SYSTEM
System DescriptionINFOID:0000000001679795
SYSTEM DESCRIPTION
Component Parts
Blower speed control system components are:• A/C auto amp.
• A/C and AV switch assembly
• Variable blower control
• Front blower motor relay
• Front blower motor
• In-vehicle sensor
• Ambient sensor
• Optical sensor
• Intake sensor
System Operation
Automatic Mode
In the automatic mode, the blower motor speed is calc ulated by the A/C auto amp. and variable blower control
based on input from the in-vehicle sensor, optical sens or, intake sensor and ambient sensor, and potentio tem-
perature control (PTC).
When the air flow is increased, the blower motor s peed is adjusted gradually to prevent a sudden increase in
air flow.
In addition to manual air flow control and the usual automat ic air flow control, starting air flow control, low
water temperature starting control and high passenger compartment temperature starting control are avail-
able.
Starting Blower Speed Control
Start up from cold soak condition (Automatic mode).
In a cold start up condition where the engine coolant temperature is below 50 °C (122° F), the blower will not
operate at blower speed 1 for a short period of time ( up to 210 seconds). The exact start delay time varies
depending on the ambient and engine coolant temperatures.
In the most extreme case (very low ambient temper ature) the blower starting delay will be 210 seconds as
described above. After the coolant temperature reaches 50 °C (122 °F), or the 210 seconds has elapsed, the
blower speed will increase to the objective blower speed.
Start up from usual operating or hot soak condition (Automatic mode).
The blower will begin operation momentarily after the AUTO switch is pushed. The blower speed will gradually
rise to the objective speed over a time period of 3 seconds or less (actual time depends on the objective
blower speed).
AWIIA0173GB
Revision: March 2010 2008 QX56

BLOWER MOTOR CONTROL SYSTEMHAC-51
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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YES >> Refer to HAC-23, "A/C System Self-Diagnosis Code Chart".
NO >> GO TO 5.
5.PERFORM A/C AND AV SWITCH ASSEMBLY SELF-DIAGNOSIS
Perform self-diagnosis to check the A/C and AV switch assembly. Refer to HAC-22, "
A/C and AV Switch
Assembly Self-Diagnosis".
Is the inspection results normal?
YES >> GO TO 6.
NO >> Replace A/C and AV switch assembly. Refer to VTL-7, "
Removal and Installation".
6.CHECK BLOWER MOTOR OPERATION
Check and verify blower motor operates manually in all speeds.
Does blower motor operate in all speeds?
YES >> GO TO 7.
NO >> Refer to HAC-51, "
Front Blower Motor Diagnosis Procedure".
7.CHECK ENGINE COOLANT TEMPERATURE SENSOR CIRCUIT
Check engine coolant temperature sensor circuit. Refer to EC-125, "
Diagnosis Procedure".
Is the inspection results normal?
YES >> GO TO 8.
NO >> Replace engine coolant temperature sensor.
8.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-4, "
Operational Check (Front)".
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair" .
NO >> Replace A/C auto amp. Refer to VTL-7, "
Removal and Installation".
Front Blower Motor Diagnosis ProcedureINFOID:0000000001679797
SYMPTOM: Blower motor operation is malfunctioning.
DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR
SYMPTOM: Blower motor operation is malfunctioning under starting
blower speed control.
1.CHECK FUSES
AWIIA0174GB
Revision: March 2010 2008 QX56

HAC-76
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
WATER VALVE CIRCUIT
WATER VALVE CIRCUIT
DescriptionINFOID:0000000001679811
COMPONENT DESCRIPTION
Water Valve
The water valve (1) cuts the flow of engine coolant to the front and
rear heater cores to allow for maximum cooling during A/C opera-
tion. It is controlled by the A/C auto amp.
Water Valve Diagnosis ProcedureINFOID:0000000001679812
DIAGNOSTIC PROCEDURE FOR WATER VALVE
1.CHECK WATER VALVE POWER AND GROUND CIRCUITS
1. Disconnect water valve connector F68.
2. Turn ignition switch ON.
3. Rotate temperature control dial (driver) to 32 °C (90° F).
4. Check voltage between water valve harness connector F68 ter- minal 1 and terminal 2 while rotating temperature control dial
(driver) to 18 °C (60° F).
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK WATER VALVE CONTROL OUTPUT CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector M50.
3. Check continuity between water valve harness connector F68 (A) terminal 2 and A/C auto amp. harness connector M50 (B)
terminal 46.
4. Check continuity between water valve harness connector F68 (A) terminal 2 and ground.
Is the inspection result normal?
YES >> Replace A/C auto amp. Refer to VTL-7, "Removal and Installation".
NO >> Repair harness or connector.
3.CHECK WATER VALVE POWER AND GROUND CIRCUITS
WJIA1791E
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
Water valve: F68 2 1Rotate temperature
control dial Battery
voltage
WJIA1794E
2 - 46 : Continuity should exist.
2 - Ground : Continuity should not exist.
AWIIA0203ZZ
Revision: March 2010 2008 QX56

INSUFFICIENT HEATINGHAC-117
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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INSUFFICIENT HEATING
Component Function CheckINFOID:0000000001679835
SYMPTOM: Insufficient heating
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERAT IONAL CHECK - TEMPERATURE INCREASE
1. Press the AUTO switch.
2. Turn the temperature control dial (driver) clockwise until 32 °C (90 °F) is displayed.
3. Check for hot air at discharge air outlets.
Can this symptom be duplicated?
YES >> GO TO 2.
NO >> Perform complete system operational check. Refer to HAC-4, "
Operational Check (Front)".
2.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 3.
3.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis. Refer to HAC-22, "
A/C Auto Amp. Self-Diagnosis".
Is the inspection results normal?
YES >> GO TO 4.
NO >> Refer to HAC-23, "
A/C System Self-Diagnosis Code Chart".
4.CHECK ENGINE COOLING SYSTEM
1. Check for proper engine coolant level. Refer to CO-10, "
Inspection".
2. Check hoses for leaks or kinks.
3. Check radiator cap. Refer to CO-10, "
Inspection".
4. Check for air in cooling system.
>> GO TO 5.
5.CHECK AIR MIX DOOR OPERATION
Check the operation of the air mix door.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Check the air mix door motor circuit. Refer to HAC-31, "
Air Mix Door Motor Component Function
Check".
6.CHECK AIR DUCTS
Check for disconnected or leaking air ducts.
Is the inspection result normal?
YES >> GO TO 7.
NO >> Repair all disconnected or leaking air ducts.
7.CHECK HEATER HOSE TEMPERATURES
1. Start engine and warm it up to normal operating temperature.
2. Touch both the inlet and outlet heater hoses.
Is the inspection result normal?
YES >> Hot inlet hose and a warm outlet hose: GO TO 8.
NO >> • Inlet hose cold: GO TO 11. • Both hoses warm: GO TO 9.
8.CHECK ENGINE COOLANT SYSTEM
Check engine control temperature sensor. Refer to EC-126, "
Component Inspection".
Revision: March 2010 2008 QX56

HAC-118
< SYMPTOM DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
INSUFFICIENT HEATING
Is the inspection result normal?
YES >> System OK.
NO >> Repair or replace as necessary. Retest.
9.CHECK HEATER HOSES
Check heater hoses for proper installation.
Is the inspection result normal?
YES >> System OK.
NO >> 1. Back flush heater core. 2. Drain the water from the system.
3. Refill system with new engine coolant. Refer to CO-11, "
Changing Engine Coolant".
4. GO TO 10 to retest.
10.CHECK HEATER HOSE TEMPERATURES
1. Start engine and warm it up to normal operating temperature.
2. Touch both the inlet and outlet heater hoses.
Is the inspection result normal?
YES >> System OK.
NO >> Replace heater core. Refer to VTL-19, "
Removal and Installation".
11 .CHECK WATER VALVE
Check the operation of the water valve. Refer to HAC-76, "
Water Valve Diagnosis Procedure".
Is the inspection result normal?
YES >> System OK.
NO >> Replace water valve.
Revision: March 2010 2008 QX56

LAN-44
< FUNCTION DIAGNOSIS >[CAN]
CAN COMMUNICATION SYSTEM
FUNCTION DIAGNOSIS
CAN COMMUNICATION SYSTEM
CAN System Specification ChartINFOID:0000000001282400
Determine CAN system type from the following specificat
ion chart. Then choose the correct diagnosis sheet.
NOTE:
Refer to LAN-14, "
Trouble Diagnosis Procedure" for how to use CAN system specification chart.
×: Applicable
VEHICLE EQUIPMENT IDENTIFICATION INFORMATION
NOTE:
Check CAN system type from the vehicle shape and equipment.
CAN Communication Signal ChartINFOID:0000000001282401
Refer to LAN-13, "How to Use CAN Communication Signal Chart" for how to use CAN communication signal
chart.
NOTE:
Refer to LAN-36, "
Abbreviation List" for the abbreviations of the connecting units.
T: Transmit R: Receive
Body type Wagon
Axle 2WD4WD
Engine VK56DE
Transmission A/T
Brake control VDC
ICC system ××
CAN system type 1234
Diagnosis sheet LAN-40
LAN-41LAN-42LAN-43
AWMIA0012GB
Signal name/Connecting unitECM
TCM
LASER ICC
ADP
AV
BCM
HVAC I-KEY M&A
STRG 4WDABS
IPDM-E
Accelerator pedal position signal T RR R R
A/C compressor request signal T R
ASCD CRUISE lamp signal T R
ASCD OD cancel request signal T R
ASCD operation signal T R
ASCD SET lamp signal T R
Battery voltage signal T R
Closed throttle position signal T RR
Cooling fan speed request signal T R
Engine coolant temperature signal T RR
Revision: March 2010 2008 QX56

PRECAUTIONSLU-3
< PRECAUTION >
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5. When the repair work is completed, return the ignition switch to the
″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of al l control units using CONSULT-III.
Precaution for Liquid GasketINFOID:0000000001538839
REMOVAL OF LIQUID GASKET SEALING
• After removing the bolts and nuts, separate the mating surface and
remove the old liquid gasket sealing using Tool.
CAUTION:
Do not damage the mating surfaces.
• Tap the seal cutter to insert it (1).
• In areas where the Tool is difficult to use, lightly tap to slide it (2).
LIQUID GASKET APPLICATION PROCEDURE
1. Remove the old liquid gasket adhering to the gasket application surface and the mating surface using suitable tool.
• Remove the liquid gasket completely from the groove of the
liquid gasket application surface, bolts, and bolt holes.
2. Thoroughly clean the mating surfaces and remove adhering moisture, grease and foreign material.
3. Attach the liquid gasket tube to the Tool. Use Genuine RTV Silicone Sealant or equivalent. Refer to
GI-15, "
Recommended Chemical Products and Sealants".
4. Apply the liquid gasket without breaks to the specified location with the specified dimensions.
• If there is a groove for the liquid gasket application, apply theliquid gasket to the groove.
• As for the bolt holes, normally apply the liquid gasket inside
the holes. If specified in the procedure, it should also be
applied outside the holes.
• Within five minutes of liquid gasket application, install the mat-
ing component.
• If the liquid gasket protrudes, wipe it off immediately.
• Do not retighten after the installation.
• Wait 30 minutes or more after installation before refilling the engine with engine oil and engine coolant.
CAUTION:
If there are specific instructions in this manual, observe them.
Tool number : KV10111100 (J-37228)
WBIA0566E
PBIC0003E
Tool number : WS39930000 ( — )
WBIA0567E
SEM159F
Revision: March 2010
2008 QX56

LU-8
< ON-VEHICLE MAINTENANCE >
ENGINE OIL
ON-VEHICLE MAINTENANCE
ENGINE OIL
InspectionINFOID:0000000001538844
OIL LEVEL
• Before starting the engine make sure the vehicle is parked on a flatand level surface, then check the oil level. If the engine is already
running, turn it off and allow 10 minutes before checking.
• Check that the oil level is within the low (L) and high (H) range as indicated on the dipstick.
• If the engine oil level is out of range, add oil as necessary. Refer to
MA-12, "
Fluids and Lubricants".
OIL APPEARANCE
• Check the engine oil for a white milky appearance or excessive contamination.
• If the engine oil is milky, it is highly probable that it is contaminated with engine coolant. Repair the broken
parts.
OIL LEAKAGE
Check for oil leakage around the following areas:
•Oil pan
• Oil pan drain plug
• Oil pressure switch
• Oil filter
• Oil cooler
• Intake valve timing control cover
• Intake valve timing control solenoid valve
• Front cover
• Mating surface between cylinder block and cylinder head
• Mating surface between cylinder head and rocker cover
• Crankshaft oil seal (front and rear)
OIL PRESSURE CHECK
WARNING:
• Be careful not to burn yoursel f, as engine oil may be hot.
• Put the selector lever in the Park “P” position.
1. Check the engine oil level. Refer to LU-8, "
Inspection".
2. Remove engine front undercover using power tool.
3. Disconnect the oil pressure switch harness connector.
4. Remove the oil pressure switch (A).
SMA954C
WBIA0791E
Revision: March 2010 2008 QX56

LU-12
< ON-VEHICLE REPAIR >
OIL COOLER
ON-VEHICLE REPAIR
OIL COOLER
Removal and InstallationINFOID:0000000001538847
WARNING:
Be careful not to burn yourself, as the engine oil and engine coolant are hot.
REMOVAL
1. Remove engine front undercover using power tool.
2. Disconnect water hoses, pinching hoses near oil cooler to prevent engine coolant from spilling.
CAUTION:
Do not spill engine coolant on the drive belt.
3. Remove oil filter. Refer to LU-11, "
Removal and Installation".
CAUTION:
Do not spill engine oi l on the drive belts.
4. Remove connector bolt, and remove oil cooler.
INSPECTION AFTER REMOVAL
Oil Cooler
Check oil cooler for cracks. Check oil cooler for clogging by blowing compressed air through engine coolant
inlet. If necessary, replace oil cooler assembly.
Relief Valve
Inspect relief valve for movement, cracks and breaks by pushing the ball. If replacement is necessary, remove
the valve by prying it out using a suitable tool. Install a new valve in place by tapping it.
INSTALLATION
WBIA0790E
1. Oil pan 2. Water hose 3. Water pipe
4. Water hose 5. Connector bolt 6. Oil filter
7. Oil cooler 8. O-ring 9. Relief valve
10. Water hose 11. Connector pipe 12. Gasket
A. To thermostat housing B. Refer to LU-11
C. To cylinder block
Revision: March 2010 2008 QX56

OIL COOLERLU-13
< ON-VEHICLE REPAIR >
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Installation is in the reverse order of removal, paying attention to the following:
• Confirm that no foreign objects are adhering to the sealing sur-
faces of the oil cooler or oil pan.
• Tighten the connecting bolt after aligning the stopper on the oil pan side with protrusion of the oil cooler.
INSPECTION AFTER INSTALLATION
1. Check levels and add engine oil and engine coolant. Refer to LU-8, "Inspection" and CO-10, "Inspection".
2. Start the engine, and check for leaks of engine oil and engine coolant.
3. Stop the engine and wait for 10 minutes.
4. Check engine oil level and engine coolant level again.
KBIA2500E
Revision: March 2010 2008 QX56