2006 INFINITI QX56 water pump

CO-1
ENGINE COOLING SYSTEM
B ENGINE
CONTENTS
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SECTION
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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

WATER PUMPCO-19
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Revision: November 2009 2006 QX56
WAT E R P U MPPFP:21020
Removal and InstallationEBS00REF
CAUTION:

When removing water pump, be careful not to get engine coolant on drive belt.

Water pump cannot be disassembled and should be replaced as a unit.
REMOVAL
1. Drain engine coolant so that no engine coolant comes out from water pump fitting hole. Refer to CO-11,
"DRAINING ENGINE COOLANT" .
CAUTION:
Perform when the engine is cold.
2. Remove the engine front undercover using power tool.
3. Remove the air duct and resonator assembly. Refer to EM-15, "
Removal and Installation" .
4. Remove the drive belt. Refer to EM-13, "
Removal and Installation" .
5. Remove the water pump pulley.
6. Remove the water pump.

Engine coolant will leak from the cylinder block, so have a receptacle ready below.
CAUTION:
Handle water pump vane so that it does not contact any other parts.
INSPECTION AFTER REMOVAL

Visually check that there is no significant dirt or rust on the water
pump body and vane.

Make sure there is no looseness in the vane shaft, and that it
turns smoothly when rotated by hand.

Replace the water pump, if necessary.
INSTALLATION
Installation is in the reverse order of removal.
KBIA2543E
1. Gasket 2. Water pump3. Water pump pulley
KBIA2552E

CO-20Revision: November 2009
WATER PUMP
2006 QX56

After installation bleed the air from the cooling system. Refer to CO-11, "REFILLING ENGINE COOLANT"
.
INSPECTION AFTER INSTALLATION

Check for leaks of engine coolant. Refer to CO-10, "CHECKING COOLING SYSTEM FOR LEAKS" .

Start and warm up engine. Visually check for leaks of the engine coolant.

DI-6
COMBINATION METERS
Revision: November 20092006 QX56
POWER SUPPLY AND GROUND CIRCUIT
Power is supplied at all times

through 10A fuse [No.19, located in the fuse block (J/B)]

to combination meter terminal 8.
With the ignition switch in the ON or START position, power is supplied

through 10A fuse [No.14, located in the fuse block (J/B)]

to combination meter terminal 24.
With the ignition switch in the ACC or ON position, power is supplied

through 10A fuse [No.4, located in the fuse block (J/B)]

to combination meter terminal 1.
Ground is supplied

to combination meter terminal 17

through body grounds M57, M61 and M79.
WATER TEMPERATURE GAUGE
The water temperature gauge indicates the engine coolant temperature.
ECM provides an engine coolant temperature signal to combination meter via CAN communication lines.
ENGINE OIL PRESSURE GAUGE
The engine oil pressure gauge indicates the engine oil pressure.
The engine oil pressure gauge is regulated by the unified meter control unit and input from the oil pressure
sensor.
A/T OIL TEMPERATURE GAUGE
The A/T oil temperature gauge indicates the A/T fluid temperature.
TCM (transmission control module) provides an A/T fluid temperature signal to combination meter via CAN
communication lines.
V O LTA G E G A U G E
The voltage gauge indicates the battery/charging system voltage.
The voltage gauge is regulated by the unified meter control unit.
TACHOMETER
The tachometer indicates engine speed in revolutions per minute (rpm).
ECM provides an engine speed signal to combination meter via CAN communication lines.
FUEL GAUGE
The fuel gauge indicates the approximate fuel level in the fuel tank.
The fuel gauge is regulated by the unified meter control unit and a variable resistor signal supplied

to combination meter terminal 15.

through fuel level sensor unit and fuel pump terminal 2

through fuel level sensor unit and fuel pump terminal 5

from combination meter terminal 16
SPEEDOMETER
ABS actuator and electric unit (control unit) provides a vehicle speed signal to the combination meter via CAN
communication lines.
CAN COMMUNICATION SYSTEM DESCRIPTION
Refer to LAN-26, "CAN COMMUNICATION" .

EC-92Revision: November 2009
TROUBLE DIAGNOSIS
2006 QX56
Symptom Matrix ChartUBS00L05
SYSTEM — BASIC ENGINE CONTROL SYSTEM
SYMPTOMRefer-
ence page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA
Fuel Fuel pump circuit 11232 22 3 2EC-604
Fuel pressure regulator system 334444444 4 EC-82
Injector circuit11232 22 2EC-598
Evaporative emission system 334444444 4 EC-32
Air Positive crankcase ventilation sys-
tem 334444444 41
EC-45
Incorrect idle speed adjustment 1 1 1 1 1EC-71
Electric throttle control actuator 112332222 2 2 EC-528
,
EC-534
,
EC-540
,
EC-545
IgnitionIncorrect ignition timing adjustment 33111 11 1EC-71
Ignition circuit 11222 22 2EC-618
Main power supply and ground circuit 22333 33 23 EC-145
Mass air flow sensor circuit
1
12 2
222 2 EC-171,
EC-180
Engine coolant temperature sensor circuit
333
EC-192,
EC-205
Air fuel ratio (A/F) sensor 1 circuit EC-213
,
EC-223
,
EC-232
,
EC-241
,
EC-575

Throttle position sensor circuit 22EC-198
,
EC-320
,
EC-483
,
EC-485
,
EC-560
Accelerator pedal position sensor circuit 3 2 1EC-453
,
EC-547
,
EC-553
,
EC-567
Knock sensor circuit 23EC-335
Crankshaft position sensor (POS) circuit 2 2 EC-340
Camshaft position sensor (PHASE) circuit 3 2EC-347

TROUBLE DIAGNOSISEC-95
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Revision: November 2009 2006 QX56
1 - 6: The numbers refer to the order of inspection.Exhaust Exhaust manifold/Tube/Muffler/
Gasket 55555 55 5 EM-21
,
EX-
3Three way catalyst
Lubrica-
tion Oil pan/Oil strainer/Oil pump/Oil
filter/Oil gallery/Oil cooler
55555 55 5EM-24
,
LU-
13 , LU-10 ,
LU-11
Oil level (Low)/Filthy oil LU-7
Cooling Radiator/Hose/Radiator filler cap
55555 55 45 CO-14
Thermostat
5CO-21
Water pump CO-19
Water galleryCO-8
Cooling fan5CO-17
Coolant level (Low)/Contami-
nated coolant 5
CO-10
IVIS (INFINITI Vehicle Immobilizer System —
NATS) 11
BL-137
SYMPTOM
Reference
page
HARD/NO START/RESTART (EXCP. HA)
ENGINE STALL
HESITATION/SURGING/FLAT SPOT
SPARK KNOCK/DETONATION
LACK OF POWER/POOR ACCELERATION
HIGH IDLE/LOW IDLE
ROUGH IDLE/HUNTING
IDLING VIBRATION
SLOW/NO RETURN TO IDLE
OVERHEATS/WATER TEMPERATURE HIGH
EXCESSIVE FUEL CONSUMPTION
EXCESSIVE OIL CONSUMPTION
BATTERY DEAD (UNDER CHARGE)
Warranty symptom code AA AB AC AD AE AF AG AH AJ AK AL AM HA

EC-314Revision: November 2009
DTC P0181 FTT SENSOR
2006 QX56
Component InspectionUBS00H39
FUEL TANK TEMPERATURE SENSOR
1. Remove fuel level sensor unit.
2. Check resistance between “fuel level sensor unit and fuel pump ”
terminals 3 and 4 by heating with hot water or heat gun as
shown in the figure.
Removal and InstallationUBS00H3A
FUEL TANK TEMPERATURE SENSOR
Refer to FL-6, "FUEL LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
Temperature °C (°F) Resistance kΩ
20 (68) 2.3 - 2.7
50 (122) 0.79 - 0.90
SEF476YA