2006 INFINITI QX56 engine

THERMOSTAT AND WATER PIPINGCO-21
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Revision: November 2009 2006 QX56
THERMOSTAT AND WATER PIPINGPFP:21200
Removal and InstallationEBS00REG
REMOVAL
Removal of Thermostat
1. Drain engine coolant from the radiator. Refer to CO-11, "DRAINING ENGINE COOLANT" .
CAUTION:
Perform when engine is cold.
2. Remove the air duct and resonator assembly. Refer to EM-15, "
Removal and Installation" .
3. Remove the engine room cover using power tool.
4. Disconnect the water suction hose from the water inlet.
5. Remove the water inlet and thermostat.
Removal of Thermostat Housing, Water Outlet and Heater Pipe
1. Remove the intake manifold. Refer to EM-17, "Removal and Installation" .
2. Remove the thermostat housing, water outlet and heater pipe.
Removal of Water Cut Valve
1. Drain the engine coolant from the radiator. Refer to CO-11, "DRAINING ENGINE COOLANT" .
KBIA2501E
1. Heater pipe2. Gasket 3. Water outlet
4. Gasket 5.O-ring 6.O-ring
7. Thermostat housing 8. Rubber ring 9. Thermostat
10. Water inlet 11. Water suction hose 12. Water suction pipe
13. Gasket 14. Heater pipe

CO-22Revision: November 2009
THERMOSTAT AND WATER PIPING
2006 QX56
CAUTION:
Perform when the engine is cold.
2. Remove the air duct and resonator assembly. Refer to EM-15, "
Removal and Installation" .
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 temper-
ature 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, "CHECKING COOLING SYSTEM FOR LEAKS" .

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

SERVICE DATA AND SPECIFICATIONS (SDS)CO-23
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Revision: November 2009 2006 QX56
SERVICE DATA AND SPECIFICATIONS (SDS)PFP:00030
Standard and LimitEBS00REH
ENGINE COOLANT CAPACITY (APPROXIMATE)
Unit: (US gal, Imp gal)
THERMOSTAT
RADIATOR
Unit: kPa (kg/cm2 , psi)
Engine coolant capacity with reservoir tank ("MAX" level)14.4 (3 3/4, 3 1/8)
Valve opening temperature80 - 84°C (176 - 183 °F)
Maximum valve lift More than 10 mm/95°C (0.39 in/203°F)
Valve closing temperature 77°C (171°F) or higher
Reservoir cap relief pressure Standard 95 - 125 (0.97- 1.28, 14 - 18)
Leakage test pressure 137 (1.4, 20)

DI-1
DRIVER INFORMATION SYSTEM
K ELECTRICAL
CONTENTS
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SECTION
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Revision: November 2009 2006 QX56
PRECAUTION .......................................................
..... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 3
PREPARATION ...................................................... ..... 4
Commercial Service Tool .................................... ..... 4
COMBINATION METERS ...................................... ..... 5
System Description ............................................. ..... 5
UNIFIED METER CONTROL UNIT ................. ..... 5
POWER SUPPLY AND GROUND CIRCUIT ... ..... 6
WATER TEMPERATURE GAUGE ................... ..... 6
ENGINE OIL PRESSURE GAUGE .................. ..... 6
A/T OIL TEMPERATURE GAUGE ................... ..... 6
VOLTAGE GAUGE ........................................... ..... 6
TACHOMETER ................................................ ..... 6
FUEL GAUGE ....................................................... 6
SPEEDOMETER .............................................. ..... 6
CAN COMMUNICATION SYSTEM DESCRIP-
TION ................................................................. ..... 6
Component Parts and Harness Connector Location ..... 7
Combination Meter .............................................. ..... 8
CHECK ............................................................. ..... 8
Schematic ........................................................... ..... 9
Wiring Diagram — METER — ............................. ... 10
Terminals and Reference Value for Combination
Meter ................................................................... ... 12
Meter/Gauge Operation and Odo/Trip Meter ...... ... 13
SELF-DIAGNOSIS FUNCTION ....................... ... 13
HOW TO INITIATE COMBINATION METER
SELF- DIAGNOSIS MODE .............................. ... 13
COMBINATION METER SELF-DIAGNOSIS
MODE FUNCTIONS ........................................ ... 13
How to Proceed With Trouble Diagnosis ............. ... 17
Diagnosis Flow .................................................... ... 17
Power Supply and Ground Circuit Inspection ..... ... 18
Symptom Chart ................................................... ... 19
Vehicle Speed Signal Inspection ......................... ... 19
Engine Oil Pressure Signal Inspection ................ ... 19
Water Temperature Signal Inspection ................. ... 21
Engine Speed Signal Inspection ......................... ... 21Fuel Level Sensor Unit Inspection .......................
... 22
FUEL LEVEL SENSOR UNIT .......................... ... 22
LOW-FUEL WARNING LAMP .......................... ... 22
Fuel Gauge Fluctuates, Indicates Wrong Value, or
Varies ................................................................... ... 24
Fuel Gauge Does Not Move to Full-position ........ ... 24
Electrical Components Inspection ....................... ... 25
FUEL LEVEL SENSOR UNIT CHECK ............. ... 25
Removal and Installation of Combination Meter .. ... 25
COMPASS AND THERMOMETER ........................ ... 26
System Description .............................................. ... 26
OUTSIDE TEMPERATURE DISPLAY .............. ... 26
DIRECTION DISPLAY ...................................... ... 26
Wiring Diagram — COMPAS — .......................... ... 27
Trouble Diagnoses .............................................. ... 28
PRELIMINARY CHECK FOR THERMOMETER ... 28
INSPECTION/COMPASS AND THERMOME-
TER .................................................................. ... 28
Calibration Procedure for Compass .................... ... 29
CORRECTION FUNCTIONS OF COMPASS ... ... 29
INITIAL CORRECTION PROCEDURE FOR
COMPASS ........................................................ ... 30
WARNING LAMPS ................................................. ... 31
Schematic ............................................................ ... 31
Wiring Diagram — WARN — ............................... ... 32
Oil Pressure Warning Lamp Stays Off (Ignition
Switch ON) .......................................................... ... 38
Oil Pressure Warning Lamp Does Not Turn Off (Oil
Pressure Is Normal) ............................................. ... 40
A/T INDICATOR ..................................................... ... 41
Wiring Diagram — AT/IND — .............................. ... 41
A/T Indicator Does Not Illuminate ........................... 42
WARNING CHIME .................................................. ... 43
Component Parts and Harness Connector Location ... 43
System Description .............................................. ... 44
FUNCTION ....................................................... ... 44
IGNITION KEY WARNING CHIME .................. ... 44
LIGHT WARNING CHIME ................................ ... 44
SEAT BELT WARNING CHIME ........................ ... 44
CAN Communication System Description ........... ... 45

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" .

COMBINATION METERSDI-13
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Revision: November 2009 2006 QX56
Meter/Gauge Operation and Odo/Trip MeterEKS00BC0
SELF-DIAGNOSIS FUNCTION
The following items can be checked during Combination Meter Self-Diagnosis Mode.

Gauge sweep and present gauge values.

Illuminates all odometer, fuel, and engine temperature segments.

Illuminates all micro controlled lamps/LED's regardless of switch configuration.

Displays estimated present battery voltage.

Displays seat belt buckle switch LH status.
HOW TO INITIATE COMBINATION METER SELF- DIAGNOSIS MODE
NOTE:
Once entered, Combination Meter Self-Diagnosis Mode will function with the ignition switch in ON or START.
Combination Meter Self-Diagnosis Mode will exit upon turning the ignition switch to OFF or ACC.
To initiate Combination Meter Self-Diagnosis Mode, refer to the following procedure.
1. Turn the ignition switch ON, while holding the odometer/trip meter switch for 5 - 8 seconds.
NOTE:
If the diagnosis function is activated the odometer/trip meter will display tESt.
COMBINATION METER SELF-DIAGNOSIS MODE FUNCTIONS
To interpret Combination Meter Self-Diagnosis Mode functions, refer to the following table.
Event Odometer Display Description of Test/Data Notes:
Odometer/trip meter A/B
switch held from 5 to 8
seconds (or until
released) tESt
Initiating self-diagnosis mode
Odometer/trip meter A/B
switch engaged and
released = next test
requested rXXXX, FAILReturn to normal opera-
tion of all lamps/LEDs and
displays hex ROM rev. If
a ROM checksum fault
exists, display alternates
between "r XXXX" and
"FAIL".
Next test requested nrXXXX Displays hex ROM rev as
stored in NVM.
Next test requested Sc1XX Displays 8-bit software
configuration value in Hex
format.Bit Coding
7-3 = reserved for future use
2 = TCS/VDC 0 = not present
1 = present
1 = Shift type 0 = Column shift
1 = Floor shift
0 = ICC 0 = not present
1 = present
Next test requested Sc2XX Displays 8-bit software
configuration value in Hex
format.Bit coding
7-0 = Reserved for future use
Next test requested EprXX Displays 8-bit software
configuration value in Hex
format.Bit Coding
7-2 = reserved for future use
1 = A/T Oil Temp (gauge)
0 = not present
1 = present
1 = Odo Units 0 = kilometers
1 = miles
Next test requested 1nFXX Displays 8-bit market info
value in Hex format.$31 = USA
$2A = Canada
Next test requested cYLXX Displays 8-bit engine con-
figuration value in Hex
format.$08 = 8 cylinder
$06 = 6 cylinder

DI-14
COMBINATION METERS
Revision: November 20092006 QX56
Next test requested bulbIlluminates all micro-con-
trolled lamps/LEDs
regardless of SW configu-
ration.
Next test requested D-HI Meter/LCD Illumination.
Next test requested (All segments illuminated) Lights all odometer/trip
meter, fuel, and engine
temperature display seg-
ments.Full daytime brightness all
LCD segments active
Next test requested N-HI Meter/LCD Illumination.
Next test requested (All segments illuminated) Lights all odometer/trip
meter, fuel, and engine
temperature display seg-
ments.Full nighttime brightness all
LCD segments active
Next test requested N-LO Meter/LCD Illumination.
Next test requested (All segments illuminated) Lights all odometer/trip
meter, fuel, and engine
temperature display seg-
ments.Min. nighttime brightness all
LCD segments active
Next test requested dS XX Current dimming step. 1-21
Next test requested EE XX, FAIL Hex EE level. If EE
checksum fault exists,
display alternates
between "EE XX" and
"FAIL".
Next test requested dtXXXX Hex coding of final manu-
facturing test date.
Next test requested GAGE Performs sweep of all
gauges, then displays
present gauge values.
Performs checksum tests
on ROM and EE.Gauges sweep within 10 sec-
onds
Next test requested FFXXXX Displays 16-bit fuel flow
constant "Q" in tenths of
cc/min in Hex format.$0000 - $FFFF
Next test requested tF Displays 16-bit tire factor
"A" in hundredths in Hex
format.$0000 - $FFFF
Next test requested oP Current oil pressure value
in A/D counts in hex for-
mat.
$00 - $FF
Next test requested ot1XX Displays oil pressure tell-
tale "on" threshold in A/D
counts in Hex format.$00 - $FF
Next test requested ot0XX Displays oil pressure tell-
tale "off" threshold in A/D
counts in Hex format.$00 - $FF
Next test requested XXXXX Raw uncompensated
english speed value in
hundredths of MPH.
Speedometer indicates
present speed.Will display "-----" if message is
not received. Will display
"99999" if data received is
invalid
Next test requested XXXXX Raw uncompensated
metric speed value in
hundredths of KPH.
Speedometer indicates
present speed.Will display "-----" if message is
not received. Will display
"99999" if data received is
invalid
Event Odometer Display Description of Test/Data Notes:

COMBINATION METERSDI-19
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Revision: November 2009 2006 QX56
Symptom ChartEKS00BC4
Vehicle Speed Signal InspectionEKS00BC5
1. CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
Refer to BRC-29, "
SELF-DIAGNOSIS" .
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "COMBINATION METER" .
NG >> Perform "Diagnostic Procedure" for displayed DTC. Refer to BRC-11, "
TROUBLE DIAGNOSIS" .
Engine Oil Pressure Signal Inspection EKS00BC6
1. CHECK OIL PRESSURE SENSOR SIGNAL
1. Turn ignition switch ON.
2. Check voltage between combination meter harness connector M24 terminal 20 and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. CHECK OIL PRESSURE SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect combination meter connector M24 and oil pressure sensor connector F4.
3. Check continuity between combination meter harness connector M24 terminal 16 and oil pressure sensor harness connector F4
terminal 3.
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "COM-
BINATION METER" .
NG >> Repair harness or connector.
Trouble phenomenon Possible cause
Improper tachometer indication. Refer to DI-21, "
Engine Speed Signal Inspection" .
Improper water temperature gauge indication. Refer to DI-21, "
Water Temperature Signal Inspection" .
Improper speedometer or odometer. Refer to DI-19, "
Vehicle Speed Signal Inspection" .
Improper fuel gauge indication. Refer to DI-22, "
Fuel Level Sensor Unit Inspection" .
Fuel warning lamp indication is irregular.
Improper A/T oil temperature gauge indication Refer to
AT-127, "
DTC P1710 A/T FLUID TEMPERATURE SEN-
SOR CIRCUIT" .
Improper voltage gauge indication Replace combination meter. Refer to IP-13, "
COMBINATION
METER" .
More than one gauge does not give proper indication.
Improper A/T position indication. Refer to DI-41, "
A/T INDICATOR" .
Illumination control does not operate properly. Refer to LT-157, "
ILLUMINATION" .
Terminals
Condition Voltage (V)
(+)
(– )
Connector Terminal
M24 20 Ground When ignition switch is in ON
position. (Engine stopped)
Ye s
Engine running. (Idle speed) Yes
WKIA1833E
Continuity should exist.
WKIA1837E