2008 INFINITI QX56 fl sensor

ENGINE MAINTENANCEMA-17
< ON-VEHICLE MAINTENANCE >
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2. Fill the radiator and the reservoir tank (to the “MAX”
line), with water. Reinstall the radiator cap and leave
the vented reservoir cap off.
3. Run the engine until it reaches normal operating temperature.
4. Press the engine accelerator two or three times under no-load.
5. Stop the engine and wait until it cools down.
6. Drain the water from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant" .
7. Repeat steps 2 through 6 until clear water begins to drain from the radiator.
Checking Fuel LineINFOID:0000000001606172
Inspect the fuel lines and fuel tank for improper mounting, leaks,
cracks, damage, loose connections, chafing, or deterioration.
As necessary, repair or replace any faulty parts.
Changing Fuel FilterINFOID:0000000001606173
The fuel filter is part of the fuel level sensor unit, fuel filter and fuel pump assembly. Refer to FL-7, "Removal
and Installation" .
WARNING:
Before replacing the fuel filter, release the fuel pressure from the fuel system. Refer to EC-494, "
Fuel
Pressure Check".
Changing Engine Air Cleaner FilterINFOID:0000000001606174
VISCOUS PAPER TYPE
NOTE:
• The viscous paper type filter does not need cleaning between replacement intervals.
• Replace the air filter as necessary for required maintenance.
1. Remove the air duct and resonator assembly.
SMA803A
1. Air cleaner case (upper) 2. Air cleaner filter3. Air cleaner case (lower)
4. Air duct and resonator assembly
WBIA0465E
Revision: March 2010 2008 QX56

MIR-8
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004873066
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inopera tive, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harn esses can be identified by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
• When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000004873067
NOTE:
• This Procedure is applied only to models with Intelligent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
• Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
• Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be rotated.
4. Perform the necessary repair operation.
Revision: March 2010 2008 QX56

MWI-2
INFORMATION DISPLAY .........................................19
INFORMATION DISPLAY : System Diagram .........20
INFORMATION DISPLAY : System Description ....20
INFORMATION DISPLAY : Component Parts Lo-
cation ................................................................... ...
21
INFORMATION DISPLAY : Component Descrip-
tion ....................................................................... ...
21
COMPASS .........................................................22
Description ........................................................... ...22
DIAGNOSIS SYSTEM (METER) .......................24
Diagnosis Description .......................................... ...24
CONSULT-III Function (METER/M&A) ................ ...25
COMPONENT DIAGNOSIS ........................28
DTC U1000 CAN COMMUNICATION ............ ...28
DTC Logic ............................................................ ...28
Diagnosis Procedure .............................................28
DTC B2205 VEHICLE SPEED CIRCUIT ...........29
Description ........................................................... ...29
DTC Logic ...............................................................29
Diagnosis Procedure .............................................29
POWER SUPPLY AND GROUND CIRCUIT .....30
COMBINATION METER ........................................ ...30
COMBINATION METER : Diagnosis Procedure ....30
BCM (BODY CONTROL MODULE) ...................... ...30
BCM (BODY CONTROL MODULE) : Diagnosis
Procedure ...............................................................
31
IPDM E/R (INTELLIGENT POWER DISTRIBU-
TION MODULE ENGINE ROOM) .......................... ...
31
IPDM E/R (INTELLIGENT POWER DISTRIBU-
TION MODULE ENGINE ROOM) : Diagnosis Pro-
cedure .....................................................................
31
FUEL LEVEL SENSOR SIGNAL CIRCUIT .......33
Description ........................................................... ...33
Component Function Check ...................................33
Diagnosis Procedure .............................................33
Component Inspection ............................................34
OIL PRESSURE SWITCH SIGNAL CIRCUIT ...35
Description ..............................................................35
Component Function Check ...................................35
Diagnosis Procedure ..............................................35
Component Inspection ............................................35
PARKING BRAKE SWITCH SIGNAL CIR-
CUIT ...................................................................
36
Description ........................................................... ...36
Component Function Check ...................................36
Diagnosis Procedure ..............................................36
Component Inspection ............................................36
WASHER LEVEL SWITCH SIGNAL CIRCUIT ...37
Description ........................................................... ...37
Diagnosis Procedure ............................................ ...37
Component Inspection ............................................37
COMPASS .........................................................38
Wiring Diagram .................................................... ...38
CLOCK ..............................................................40
Wiring Diagram .................................................... ...40
ECU DIAGNOSIS .......................................42
COMBINATION METER ................................. ...42
Reference Value .................................................. ...42
Wiring Diagram .......................................................44
Fail Safe ..................................................................61
DTC Index ...............................................................62
BCM (BODY CONTROL MODULE) ..................64
Reference Value .................................................. ...64
Terminal Layout ......................................................64
Physical Values .......................................................64
Wiring Diagram .......................................................64
DTC Inspection Priority Chart ...............................64
DTC Index ..............................................................64
IPDM E/R (INTELLIGENT POWER DISTRI-
BUTION MODULE ENGINE ROOM) .................
65
Reference Value .................................................. ...65
Terminal Layout ......................................................65
Physical Values .......................................................65
Wiring Diagram .......................................................65
Fail Safe .................................................................65
DTC Index ..............................................................65
SYMPTOM DIAGNOSIS ............................66
THE FUEL GAUGE POINTER DOES NOT
MOVE .............................................................. ...
66
Description ........................................................... ...66
Diagnosis Procedure ...............................................66
THE FUEL GAUGE POINTER DOES NOT
MOVE TO "F" WHEN REFUELING ..................
67
Description ........................................................... ...67
Diagnosis Procedure ...............................................67
THE OIL PRESSURE WARNING LAMP
DOES NOT TURN ON .................................... ...
68
Description ........................................................... ...68
Diagnosis Procedure ...............................................68
THE OIL PRESSURE WARNING LAMP
DOES NOT TURN OFF .................................. ...
69
Description ........................................................... ...69
Diagnosis Procedure ...............................................69
THE PARKING BRAKE RELEASE WARNING
CONTINUES DISPLAYING, OR DOES NOT
DISPLAY ............................................................
70
Description ........................................................... ...70
Diagnosis Procedure ...............................................70
Revision: March 2010 2008 QX56

MWI
METER SYSTEMMWI-7
< FUNCTION DIAGNOSIS >
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METER SYSTEM : Com ponent Parts LocationINFOID:0000000001691236
METER SYSTEM : Component DescriptionINFOID:0000000001691237
1. IPDM E/R E122, E124 2. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control unit) E1256. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Unit Description
Combination meter Controls the following with the signals received from each unit via CAN communication and the sig-
nals from switches and sensors.
• Speedometer
• Tachometer
• Engine coolant temperature gauge • Fuel gauge
• Engine oil pressure gauge • Odo/trip meter
• Voltage gauge • Indicator lamps
• Warning lamps • Warning chime
• Information display
IPDM E/R IPDM E/R reads the ON/OFF signals of the oil pressure switch and transmits the oil pressure switch
signal to the combination meter via BCM with CAN communication line.
Fuel level sensor unit Refer to MWI-33, "
Description".
Oil pressure switch Refer to MWI-35, "
Description".
ECM Transmits the following signals to the combination meter with CAN communication line.
• Engine speed signal
• Engine coolant temperature signal
• Fuel consumption monitor signal
Revision: March 2010 2008 QX56

MWI
METER SYSTEMMWI-9
< FUNCTION DIAGNOSIS >
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SPEEDOMETER : Compone nt Parts LocationINFOID:0000000001696366
SPEEDOMETER : Component DescriptionINFOID:0000000001691241
TACHOMETER
TACHOMETER : System DiagramINFOID:0000000001691242
1. IPDM E/R E122, E124 2. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control unit) E1256. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Unit Description
Combination meter Indicates the vehicle speed according to the vehicle speed signal received from ABS actuator and
electric unit (control unit) via CAN communication.
ABS actuator and electric unit
(control unit) Transmits the vehicle speed signal to the combination meter with CAN communication line.
SKIB6904E
Revision: March 2010
2008 QX56

MWI-10
< FUNCTION DIAGNOSIS >
METER SYSTEM
TACHOMETER : System Description
INFOID:0000000001691243
The tachometer indicates engine speed in revolutions per minute (rpm).
The ECM provides an engine speed signal to the co mbination meter via CAN communication lines.
TACHOMETER : Component Parts LocationINFOID:0000000001696367
TACHOMETER : Component DescriptionINFOID:0000000001691245
ENGINE COOLANT TEMPERATURE GAUGE
1. IPDM E/R E122, E1242. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control
unit) E125 6. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Unit Description
Combination meter Indicates the engine speed in RPM according to the engine speed signal received from ECM via
CAN communication.
ECM Transmits the engine speed signal to the combination meter with CAN communication line.
Revision: March 2010 2008 QX56

MWI
METER SYSTEMMWI-11
< FUNCTION DIAGNOSIS >
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ENGINE COOLANT TEMPERATURE GAUGE : System DiagramINFOID:0000000001691246
ENGINE COOLANT TEMPERATURE GAUGE : System DescriptionINFOID:0000000001691247
The engine coolant temperature gauge indicates the engine coolant temperature.
The ECM provides an engine coolant temperature signal to the combination meter via CAN communication
lines.
ENGINE COOLANT TEMPERATURE GA UGE : Component Parts Location
INFOID:0000000001696368
SKIB6905E
1. IPDM E/R E122, E124 2. Combination meter M23, M24 3. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover re-
moved)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (control unit) E1256. Oil pressure switch F4
A: Oil pan (upper)
7. A/T assembly F9 8. BCM M18, M19 (view with instrument
lower panel LH removed)
AWNIA0201ZZ
Revision: March 2010 2008 QX56

MWI-12
< FUNCTION DIAGNOSIS >
METER SYSTEM
ENGINE COOLANT TEMPERATURE GAUGE : Component Description
INFOID:0000000001691249
FUEL GAUGE
FUEL GAUGE : System DiagramINFOID:0000000001691250
FUEL GAUGE : System DescriptionINFOID:0000000001691251
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 by the fuel
level sensor unit.
FUEL GAUGE : Compone nt Parts LocationINFOID:0000000001696369
Unit Description
Combination meter Indicates the engine coolant temperature according to the engine coolant temperature signal re-
ceived from ECM via CAN communication.
ECM Transmits the engine coolant temperature signal to the combination meter via CAN communication.
AWNIA0004GB
AWNIA0201ZZ
Revision: March 2010 2008 QX56