2006 INFINITI QX56 ignition

OVERHEATING CAUSE ANALYSISCO-7
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Revision: November 2009 2006 QX56
Except cool-
ing system
parts mal-
function—
Overload on engine Abusive driving
High engine rpm under no
load
Driving in low gear for
extended time
Driving at extremely high
speed
Powertrain system mal-
function
—
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

ENGINE COOLANTCO-11
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Revision: November 2009 2006 QX56
DRAINING ENGINE COOLANT
1. Turn ignition switch ON and set temperature control lever all the way to HOT position or the highest tem-
perature position. Wait 10 seconds and turn ignition switch OFF.
2. Remove the engine front undercover using power tool.
3. Open the radiator drain plug at the bottom of the radiator, and remove the radiator filler cap. This is the only step required
when partially draining the cooling system (radiator only).
CAUTION:
Do not to allow the coolant to contact the drive belts.
4. When draining all of the coolant in the system for engine removal or repair, it is necessary to drain the cylinder block.
Remove the RH cylinder block drain plug to drain the right bank
and the oil cooler hose to drain the left bank as shown.
5. Remove the reservoir tank to drain the engine coolant, then clean the reservoir tank before installing it.
6. Check the drained coolant for contaminants such as rust, corrosion or discoloration. If the coolant is contaminated, flush the engine cooling system. Refer to CO-12, "
FLUSHING COOLING
SYSTEM" .
REFILLING ENGINE COOLANT
1. Close the radiator drain plug. Install the reservoir tank, cylinder block drain plug, and the oil cooler hose, if
removed for a total system drain or for engine removal or repair.

The radiator must be completely empty of coolant and water.

Apply sealant to the threads of the cylinder block drain plug. Use Genuine High Performance Thread
Sealant or equivalent. Refer to GI-46, "
Recommended Chemical Products and Sealants" .
2. Set the vehicle heater controls to the full HOT and heater ON position. Turn the vehicle ignition ON with the engine OFF as necessary to activate the heater mode.
3. Remove the vented reservoir cap and replace it with a non-vented reservoir cap before filling the cooling system.
WBIA0391E
PBIC0146E
WBIA0392E
Radiator drain plug : Refer to CO-14, "RADIATOR" .
RH cylinder block drain plug : Refer to EM-78, "
CYLINDER BLOCK" .

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

COMBINATION METERSDI-5
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Revision: November 2009 2006 QX56
COMBINATION METERSPFP:24814
System DescriptionEKS00BBU
UNIFIED METER CONTROL UNIT

Speedometer, odometer, tachometer, fuel gauge, oil pressure gauge, voltage gauge, A/T oil temperature
gauge, and water temperature gauge are controlled by the unified meter control unit, which is built into the
combination meter.

Warning indicators are controlled by signals drawn from the CAN communication system, BCM (body con-
trol module), and components connected directly to the combination meter.

Digital meter is adopted for odometer/trip meters*, as well as the A/T position indicator display.
*The record of the odometer is kept even if the battery cable is disconnected.

Odometer/trip meters and A/T indicator segments can be checked in diagnosis mode.

Meters/gauges can be checked in diagnosis mode.
Illumination control
The unified meter control unit outputs the speedometer, odometer/trip meters, tachometer, oil pressure gauge,
voltage meter, A/T indicator, A/T temperature gauge, fuel and temperature gauge lighting when the ignition
switch is turned on. When the lighting switch is turned on, the illumination control switch can be used to adjust
the brightness of the combination meter illumination and the odometer/trip meters and meter illumination.
When the ignition switch is turned from the OFF to the ON position, the combination meter dial lighting will
remain off for 0.7 seconds. For additional combination meter illumination control information, refer to LT- 1 5 7 ,
"System Description" .

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" .

DI-12
COMBINATION METERS
Revision: November 20092006 QX56
Terminals and Reference Value for Combination MeterEKS00BBZ
Terminal
No. Wire
color Item Condition
Reference value (V)
(Approx.)
Ignition
switch Operation or condition
1O Ignition switch ACC or
ON ACC
— Battery voltage
8 Y/R Battery power supply OFF —Battery voltage
11 L C A N - H —— —
12 P CAN-L —— —
15 Y/L Fuel level sensor signal ——Refer to
DI-22, "
Fuel Level Sensor
Unit Inspection" .
16 B/P Fuel level sensor and oil
pressure sensor ground
ON
— 0V
17 B Ground OFF— 0V
18 BR Illumination control switch —Lighting switch ON Refer to
LT-158, "
ILLUMINATION
OPERATION BY LIGHTING
SWITCH" .
20 Y Oil pressure sensor sig-
nal
ON
— 0 - 5V
22 GR/L Oil pressure sensor refer-
ence voltage ON
— 5V
24 O/L Ignition switch ON or
START ON
— Battery voltage

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

COMBINATION METERSDI-17
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Revision: November 2009 2006 QX56
How to Proceed With Trouble DiagnosisEKS00BC1
1. Confirm the symptom or customer complaint.
2. Perform diagnosis according to diagnosis flow. Refer to DI-17, "
Diagnosis Flow" .
3. According to the symptom chart, repair or replace the cause of the symptom.
4. Does the meter operate normally? If so, go to 5. If not, go to 2.
5. Inspection End.
Diagnosis FlowEKS00BC2
1. CHECK WARNING INDICATOR ILLUMINATION
1. Turn ignition switch ON.
2. Make sure warning indicators (such as malfunction indicator lamp and oil pressure low/coolant tempera- ture high warning indicator) illuminate.
Do warning indicators illuminate?
YES >> GO TO 2.
NO >> Check ignition power supply system of combination meter. Refer to DI-18, "
Power Supply and
Ground Circuit Inspection" .
2. CHECK SELF-DIAGNOSIS OPERATION OF COMBINATION METER
Perform combination meter self-diagnosis. Refer to DI-13, "
SELF-DIAGNOSIS FUNCTION" .
Does self-diagnosis function operate?
YES >> GO TO 3.
NO >> Check combination meter power supply and ground circuit. Refer to DI-18, "
Power Supply and
Ground Circuit Inspection" .
3. CHECK ODOMETER OPERATION
Check segment display status of odometer.
Is the display normal?
YES >> GO TO 4.
NO >> Replace the combination meter. Refer to IP-13, "
COM-
BINATION METER" .
4. CHECK COMBINATION METER CIRCUIT
Check indication of each meter/gauge in self-diagnosis mode.
OK or NG
OK >> Go to DI-19, "Symptom Chart" .
NG >> Replace the combination meter. Refer to IP-13, "
COM-
BINATION METER" .
WKIA1531E
WKIA1814E