2006 INFINITI QX56 heating

ATC-2Revision: November 20092006 QX56
CONSULT-II BASIC OPERATION ....................
... 34
SELF-DIAGNOSIS ........................................... ... 35
DATA MONITOR ............................................... ... 35
CONSULT-II Function (BCM) ............................... ... 37
CONSULT-II BASIC OPERATION .................... ... 37
DATA MONITOR ............................................... ... 38
How to Perform Trouble Diagnosis for Quick and
Accurate Repair ................................................... ... 39
WORK FLOW ................................................... ... 39
SYMPTOM TABLE ........................................... ... 39
Component Parts and Harness Connector Location ... 40
ENGINE COMPARTMENT ............................... ... 40
FRONT PASSENGER COMPARTMENT ......... ... 41
REAR PASSENGER COMPARTMENT ............... 42
Schematic ............................................................ ... 43
Wiring Diagram — A/C,A — ................................ ... 44
Front Air Control Terminals and Reference Value ... 54
PIN CONNECTOR TERMINAL LAYOUT ......... ... 54
TERMINALS AND REFERENCE VALUE FOR
FRONT AIR CONTROL .................................... ... 54
A/C System Self-diagnosis Function ................... ... 56
DESCRIPTION ................................................. ... 56
Operational Check (Front) ................................... ... 58
CHECKING MEMORY FUNCTION .................. ... 58
CHECKING BLOWER ...................................... ... 58
CHECKING DISCHARGE AIR ......................... ... 58
CHECKING RECIRCULATION (, ONLY) .......... ... 58
CHECKING TEMPERATURE DECREASE ...... ... 58
CHECKING TEMPERATURE INCREASE ....... ... 59
CHECK A/C SWITCH ....................................... ... 59
CHECKING AUTO MODE ................................ ... 59
Operational Check (Rear) .................................... ... 60
CHECKING BLOWER ...................................... ... 60
CHECKING TEMPERATURE DECREASE ...... ... 60
CHECKING TEMPERATURE INCREASE ....... ... 60
Power Supply and Ground Circuit for Front Air Con-
trol ........................................................................ ... 61
INSPECTION FLOW ........................................ ... 61
COMPONENT DESCRIPTION ......................... ... 62
DIAGNOSTIC PROCEDURE FOR A/C SYSTEM ... 62
Mode Door Motor Circuit ........................................ 64 INSPECTION FLOW ........................................ ... 64
SYSTEM DESCRIPTION ................................. ... 65
COMPONENT DESCRIPTION ......................... ... 66
DIAGNOSTIC PROCEDURE FOR MODE
DOOR MOTOR ................................................ ... 66
Air Mix Door Motor Circuit ................................... ... 70
INSPECTION FLOW ........................................ ... 70
SYSTEM DESCRIPTION ................................. ... 71
COMPONENT DESCRIPTION ......................... ... 72
DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (DRIVER) ................................ ... 72
DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER) ....................... ... 76
DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (REAR) ................................... ... 79
Intake Door Motor Circuit ..................................... ... 83
INSPECTION FLOW ........................................ ... 83
SYSTEM DESCRIPTION ................................. ... 84COMPONENT DESCRIPTION .........................
... 85
DIAGNOSTIC PROCEDURE FOR INTAKE
DOOR MOTOR ................................................. ... 85
Defroster Door Motor Circuit ................................ ... 87
SYMPTOM: ....................................................... ... 87
INSPECTION FLOW ......................................... ... 87
SYSTEM DESCRIPTION .................................. ... 88
COMPONENT DESCRIPTION ......................... ... 88
DIAGNOSTIC PROCEDURE FOR
DEFROSTER DOOR MOTOR .......................... ... 89
Front Blower Motor Circuit ................................... ... 93
INSPECTION FLOW ......................................... ... 93
SYSTEM DESCRIPTION .................................. ... 94
COMPONENT DESCRIPTION ......................... ... 95
DIAGNOSTIC PROCEDURE FOR BLOWER
MOTOR ............................................................. ... 95
COMPONENT INSPECTION ............................ .100
Rear Blower Motor Circuit .................................... .101
INSPECTION FLOW ......................................... .101
SYSTEM DESCRIPTION .................................. .102
DIAGNOSTIC PROCEDURE FOR REAR
BLOWER MOTOR ............................................ .102
COMPONENT INSPECTION ............................ .110
Rear Air Control Circuit ........................................ .112
INSPECTION FLOW ......................................... .112
SYSTEM DESCRIPTION .................................. .113
DIAGNOSTIC PROCEDURE FOR REAR AIR
CONTROL ........................................................ .113
Magnet Clutch Circuit ........................................... .115
INSPECTION FLOW ......................................... .115
SYSTEM DESCRIPTION .................................. .116
DIAGNOSTIC PROCEDURE FOR MAGNET
CLUTCH ........................................................... .116
Insufficient Cooling ............................................... .121
INSPECTION FLOW ......................................... .121
PERFORMANCE TEST DIAGNOSES ............. .122
PERFORMANCE CHART ................................. .124
TROUBLE DIAGNOSES FOR UNUSUAL PRES-
SURE ................................................................ .125
Insufficient Heating .............................................. .128
INSPECTION FLOW ......................................... .128
Noise .................................................................... .129
INSPECTION FLOW ......................................... .129
Self-diagnosis ...................................................... .130
INSPECTION FLOW ......................................... .130
Memory Function ................................................. .131
INSPECTION FLOW ......................................... .131
Water Valve Circuit ............................................... .132
COMPONENT DESCRIPTION ......................... .132
DIAGNOSTIC PROCEDURE FOR WATER
VALVE ............................................................... .132
Ambient Sensor Circuit ........................................ .134
COMPONENT DESCRIPTION ......................... .134
AMBIENT TEMPERATURE INPUT PROCESS .134
DIAGNOSTIC PROCEDURE FOR AMBIENT
SENSOR ........................................................... .134
COMPONENT INSPECTION ............................ .136
In-vehicle Sensor Circuit ...................................... .137
COMPONENT DESCRIPTION ......................... .137

TROUBLE DIAGNOSISATC-39
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
How to Perform Trouble Diagnosis for Quick and Accurate RepairEJS003XF
WORK FLOW
SYMPTOM TABLE
*1AT C - 5 8 , "Operational Check (Front)"
or ATC-60, "
Operational Check
(Rear)" .
SHA900E
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System. AT C - 6 1
A/C system display is malfunctioning. Go to Navigation System. AV- 8 4
A/C system cannot be controlled.Go to Self-diagnosis Function. AT C - 5 6
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor. AT C - 6 4
Mode door motor is malfunctioning.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor. AT C - 7 0
Air mix door motor is malfunctioning.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor. AT C - 8 3
Intake door motor is malfunctioning.
Defroster door motor is malfunctioning. Go to Trouble Diagnosis Procedure for Defroster Door Motor. AT C - 8 7
Front blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Front Blower Motor.
AT C - 9 3
Rear blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Rear Blower Motor.
AT C - 1 0 1
Rear discharge air temperature and/or air
outlet does not change.Go to Trouble Diagnosis Procedure for Rear Air Control circuit.
AT C - 11 2
Magnet clutch does not engage.Go to Trouble Diagnosis Procedure for Magnet Clutch. AT C - 11 5
Insufficient coolingGo to Trouble Diagnosis Procedure for Insufficient Cooling. AT C - 1 2 1
Insufficient heatingGo to Trouble Diagnosis Procedure for Insufficient Heating. AT C - 1 2 8
NoiseGo to Trouble Diagnosis Procedure for Noise. AT C - 1 2 9
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis. AT C - 1 3 0
Memory function does not operate.Go to Trouble Diagnosis Procedure for Memory Function. AT C - 1 3 1

TROUBLE DIAGNOSISATC-59
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
CHECKING TEMPERATURE INCREASE
1. Rotate temperature control dial clockwise (driver side or passenger side) until 32°C (90 °F) is displayed.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-128,
"Insufficient Heating" . If air mix door motor appears to be malfunctioning, go to AT C - 7 2 , "DIAGNOSTIC PRO-
CEDURE FOR AIR MIX DOOR MOTOR (DRIVER)" or AT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER)" .
If OK, continue with next check.
CHECK A/C SWITCH
1. Press A/C switch when AUTO switch is ON, or in manual mode.
2. A/C switch indicator will turn ON.

Confirm that the compressor clutch engages (sound or visual inspection).
NOTE:
If current mode setting is DEF or D/F, compressor clutch may already be engaged.
If NG, go to trouble diagnosis procedure for AT C - 11 5
.
If OK, continue with next check.
CHECKING AUTO MODE
1. Press AUTO switch.
2. Display should indicate AUTO.

If ambient temperature is warm, and selected temperature is cool, confirm that the compressor clutch
engages (sound or visual inspection). (Discharge air and blower speed will depend on ambient, in-vehi-
cle, and set temperatures.)
If NG, go to trouble diagnosis procedure for AT C - 6 1 , "
Power Supply and Ground Circuit for Front Air Control" ,
then if necessary, trouble diagnosis procedure for AT C - 11 5 , "
Magnet Clutch Circuit" .
If all operational checks are OK (symptom cannot be duplicated), go to malfunction Simulation Tests in AT C -
39, "How to Perform Trouble Diagnosis for Quick and Accurate Repair" and perform tests as outlined to simu-
late driving conditions environment. If symptom appears. Refer to AT C - 3 9 , "
How to Perform Trouble Diagnosis
for Quick and Accurate Repair" , AT C - 3 9 , "SYMPTOM TABLE" and perform applicable trouble diagnosis pro-
cedures.

ATC-60
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Operational Check (Rear)EJS003XM
The purpose of the operational check is to confirm that the system operates properly.
CHECKING BLOWER
1. Turn the rear blower control dial to switch position "1". Blower should operate on low speed.
2. Turn the rear blower control dial counterclockwise to switch position "2", "3", and "4" until all speeds are
checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-101, "
Rear Blower Motor Circuit" .
If OK, continue the check.
CHECKING TEMPERATURE DECREASE
1. Rotate temperature and mode dial fully counterclockwise.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation if OK, go to trouble diagnosis procedure for ATC-121,
"Insufficient Cooling" . If air mix door motor appears to be malfunctioning, go to AT C - 7 9 , "DIAGNOSTIC PRO-
CEDURE FOR AIR MIX DOOR MOTOR (REAR)" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature and mode dial clockwise.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to trouble diagnosis procedure for ATC-128,
"Insufficient Heating" . If air mix door motor appears to be malfunctioning, go to AT C - 7 9 , "DIAGNOSTIC PRO-
CEDURE FOR AIR MIX DOOR MOTOR (REAR)" .
If OK, continue the check. Conditions : Engine running and at normal operating temperature

ATC-128
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Insufficient HeatingEJS003XX
SYMPTOM: Insufficient heating
INSPECTION FLOW
*1ATC-58, "Operational Check (Front)"
or AT C - 6 0 , "
Operational Check
(Rear)"
*2 AT C - 7 0 , "Air Mix Door Motor Circuit"*3ATC-56, "A/C System Self-diagno-
sis Function"
*4 ATC-57, "SELF-DIAGNOSIS CODE
CHART"
*5AT C - 9 3 , "Front Blower Motor Circuit"*6EC-192, "DTC P0117, P0118 ECT
SENSOR"
*7 EM-13, "Checking Drive Belts"*8ATC-132, "Water Valve Circuit"
WJIA1889E

BL-190
BODY REPAIR
Revision: November 20092006 QX56
Precautions in Repairing High Strength SteelEIS004TF
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 appro-
priate.)

When straightening body panels, use caution in pulling any
HSS panel. Because HSS is very strong, pulling may cause
deformation in adjacent portions of the body. In this case,
increase the number of measuring points, and carefully pull
the HSS panel.

When cutting HSS panels, avoid gas (torch) cutting if possi-
ble. Instead, use a saw to avoid weakening surrounding areas
due to heat. If gas (torch) cutting is unavoidable, allow a mini-
mum margin of 50 mm (1.97in).
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
PIIA0116E
PIIA0117E

CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
C
DE
F
G H
I
J
K L
M
SECTION
A
CO
Revision: November 2009 2006 QX56
PRECAUTIONS .....................................................
..... 2
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 2
Precautions for Liquid Gasket ............................. ..... 2
REMOVAL OF LIQUID GASKET SEALING ..... ..... 2
LIQUID GASKET APPLICATION PROCEDURE ..... 2
PREPARATION ...................................................... ..... 4
Special Service Tools .......................................... ..... 4
Commercial Service Tools ................................... ..... 4
OVERHEATING CAUSE ANALYSIS ..................... ..... 6
Troubleshooting Chart ......................................... ..... 6
COOLING SYSTEM ............................................... ..... 8
Cooling Circuit .......................................................... 8
System Drawing ....................................................... 9
ENGINE COOLANT ............................................... ... 10
Inspection ............................................................ ... 10
LEVEL CHECK ................................................ ... 10
CHECKING COOLING SYSTEM FOR LEAKS ... 10
CHECKING RESERVOIR CAP ........................ ... 10
CHECKING RADIATOR CAP ........................... ... 10
Changing Engine Coolant ................................... ... 10
DRAINING ENGINE COOLANT ...................... .... 11
REFILLING ENGINE COOLANT ..................... .... 11
FLUSHING COOLING SYSTEM ...................... ... 12
RADIATOR ............................................................. ... 14
Removal and Installation ..................................... ... 14
REMOVAL ........................................................ ... 14
INSTALLATION ................................................ ... 16INSPECTION AFTER INSTALLATION .............
... 16
Checking Radiator ............................................... ... 16
ENGINE COOLING FAN ........................................ ... 17
Removal and Installation (Crankshaft Driven Type) ... 17
REMOVAL ........................................................ ... 17
INSPECTION AFTER REMOVAL .................... ... 17
INSTALLATION ................................................ ... 17
INSPECTION AFTER INSTALLATION ............. ... 17
Removal and Installation (Motor Driven Type) .... ... 18
REMOVAL ........................................................ ... 18
INSTALLATION ................................................ ... 18
WATER PUMP ....................................................... ... 19
Removal and Installation ..................................... ... 19
REMOVAL ........................................................ ... 19
INSPECTION AFTER REMOVAL .................... ... 19
INSTALLATION ................................................ ... 19
INSPECTION AFTER INSTALLATION ............. ... 20
THERMOSTAT AND WATER PIPING ................... ... 21
Removal and Installation ..................................... ... 21
REMOVAL ........................................................ ... 21
INSPECTION AFTER REMOVAL .................... ... 22
INSTALLATION ................................................ ... 22
INSPECTION AFTER INSTALLATION ............. ... 22
SERVICE DATA AND SPECIFICATIONS (SDS) ... ... 23
Standard and Limit ............................................... ... 23
ENGINE COOLANT CAPACITY (APPROXI-
MATE) ............................................................... ... 23
THERMOSTAT ................................................. ... 23
RADIATOR ....................................................... ... 23

CO-6Revision: November 2009
OVERHEATING CAUSE ANALYSIS
2006 QX56
OVERHEATING CAUSE ANALYSISPFP:00012
Troubleshooting ChartEBS00RE6
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
paper 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 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 systemCylinder head deterioration
Cylinder head gasket dete-
rioration