2008 INFINITI QX56 fl sensor

TERMINOLOGYGI-19
< HOW TO USE THIS MANUAL >
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***: Not applicable Transmission control module TCM A/T control unit
Turbocharger TC Turbocharger
Vehicle speed sensor VSS Vehicle speed sensor
Volume air flow sensor VAFS Air flow meter
Warm up oxidation catalyst WU-OC Catalyst
Warm up oxidation catalytic converter sys-
tem
WU-OC system ***
Warm up three way catalyst WU-TWC Catalyst
Warm up three way catalytic converter sys-
tem WU-TWC system
***
Wide open throttle position switch WOTP switchFull switch
NEW TERM
NEW ACRONYM /
ABBREVIATION OLD TERM
Revision: March 2010
2008 QX56

GI-24
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
DescriptionINFOID:0000000001539205
Observe the following precautions to ensure safe and proper servicing. These precautions are not
described in each individual section.
Precaution for Supplemental Restraint Syst em (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000006054104
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:0000000004900859
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.
Revision: March 2010 2008 QX56

PRECAUTIONSGI-27
< PRECAUTION >
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system. The connectors should be disconnected only when working according to the WORK FLOW of
TROUBLE DIAGNOSES in EC and TM sections.
Three Way CatalystINFOID:0000000001539210
If a large amount of unburned fuel flows into the catalyst, the catalyst temperature will be excessively high. To
prevent this, follow the instructions.
• Use unleaded gasoline only. Leaded gasoline will seriously damage the three way catalyst.
• When checking for ignition spark or measuring engine compression, make tests quickly and only when nec-
essary.
• Do not run engine when the fuel tank level is low, otherwise the engine may misfire, causing damage to the
catalyst.
Do not place the vehicle on flammable material. Keep flammable material off the exhaust pipe and the three
way catalyst.
Precaution for Fuel (Unlead ed Premium Gasoline Recommended)INFOID:0000000006211825
INFINITI recommends the use of unleaded premium gasoline with an octane rating of at least 91 AKI (Anti-
Knock Index) number (Research octane number 96).
If unleaded premium gasoline is not available, unleaded regular gasoline with an octane rating of at least 87
AKI number (Research octane number 91) can be us ed, but only under the following precautions:
• have the fuel tank filled only partially with unleaded regular gasoline, and fill up with unleaded premium gas- oline as soon as possible.
• avoid full throttle driving and abrupt acceleration.
However, for maximum vehicle performance, the u se of unleaded premium gasoline is recommended.
CAUTION:
Do not use leaded gasoline. Usin g leaded gasoline will damage the three way catalyst. Using a fuel
other than that specified could adversely affect the emission cont rol devices and systems, and could
also affect the warranty coverage validity.
Multiport Fuel Inje ction System or Engine Control SystemINFOID:0000000001539213
• Before connecting or disconnecting any harness connector for the
multiport fuel injection system or ECM:
Turn ignition switch to “OFF” position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.
• Before disconnecting pressurized fuel line from fuel pump to injec- tors, be sure to release fuel pressure.
• Be careful not to jar components such as ECM and mass air flow
sensor.
HosesINFOID:0000000001539214
HOSE REMOVAL AND INSTALLATION
• To prevent damage to rubber hose, do not pry off rubber hose withtapered tool or screwdriver.
SGI787
SMA019D
Revision: March 2010 2008 QX56

SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-39
< BASIC INSPECTION >
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lowing section illustrates ways to simulate the c onditions/environment under which the owner experiences an
electrical incident.
The section is broken into the six following topics:• Vehicle vibration
• Heat sensitive
• Freezing
• Water intrusion
• Electrical load
• Cold or hot start up
Get a thorough description of the incident from the customer . It is important for simulating the conditions of the
problem.
VEHICLE VIBRATION
The problem may occur or become worse while driving on a rough road or when engine is vibrating (idle with
A/C on). In such a case, you will want to check for a vibration related condition. Refer to the following illustra-
tion.
Connector & Harness
Determine which connectors and wiring harness would affect the electrical system you are inspecting. Gently
shake each connector and harness while monitoring the syst em for the incident you are trying to duplicate.
This test may indicate a loose or poor electrical connection.
Hint
Connectors can be exposed to moisture. It is possible to get a thin film of corrosion on the connector termi-
nals. A visual inspection may not reveal this without disconnecting the connector. If the problem occurs inter-
mittently, perhaps the problem is caused by corrosi on. It is a good idea to disconnect, inspect and clean the
terminals on related connectors in the system.
Sensor & Relay
Gently apply a slight vibration to sensors and relays in the system you are inspecting.
This test may indicate a loose or poorly mounted sensor or relay.
Engine Compartment
There are several reasons a vehicle or engine vibration could cause an electrical complaint. Some of the
things to check for are:
• Connectors not fully seated.
• Wiring harness not long enough and is being stressed due to engine vibrations or rocking.
• Wires laying across brackets or moving components.
• Loose, dirty or corroded ground wires.
• Wires routed too close to hot components.
To inspect components under the hood, start by verifyi ng the integrity of ground connections. (Refer to Ground
Inspection described later.) First check that the system is properly grounded. Then check for loose connection
by gently shaking the wiring or components as previous ly explained. Using the wiring diagrams inspect the
wiring for continuity.
Behind the Instrument Panel
An improperly routed or improperly clamped harness can become pinched during accessory installation. Vehi-
cle vibration can aggravate a harness which is routed along a bracket or near a screw.
Under Seating Areas
SGI839
Revision: March 2010 2008 QX56

GI-46
< BASIC INSPECTION >
CONSULT-III CHECKING SYSTEM
CONSULT-III CHECKING SYSTEM
DescriptionINFOID:0000000001539228
• When CONSULT-III is connected with a data link connectorequipped on the vehicle side, it will communicate with the control
unit equipped in the vehicle and then enable various kinds of diag-
nostic tests.
• Refer to “CONSULT-III Operation Manual” for more information.
Function and System ApplicationINFOID:0000000001555032
1 : Hood release handle
2 : Data link connector
ALBIA0047ZZ
Diagnostic test mode Function
ENGINE
TRANSMISSION
ICC
*1
ABS
AIR BAG
IPDM E/R
BCM
METER/M&A
INTELLIGENT KEY
AUTO DRIVE POS.
REARVIEW CAMERA
AIR LEVELIZER MULTI AV
ALL MODE AWD/4WD
*2
HVAC
SONAR
Work support This mode enables a technician to adjust some devic-
es faster and more accurately by following the indica-
tions on CONSULT-III. x - xx - - x - xxxx - - - -
Self-diagnostic Self-diagnostic can be performed quickly. ----x-----------
Self-diagnostic re-
sults Self-diagnostic results can be read and erased quick-
ly.
xxxx - xxxxx - xxxxx
Trouble diagnostic
record Current self-diagnostic results and all trouble diag-
nostic records previously stored can be read.
--- - x--- - -------
Data monitor Input/Output data in the ECM can be read. xxxx - xxxxxxxxxxx
Data monitor (spec)Data monitor specification can be read. x---------------
CAN diagnosis The condition of CAN communication can be indicat-
ed by a topology.
xxxxxxxxxx - - xxx -
CAN diagnosis sup-
port monitor The communication condition of CAN communication
line can be read.
xxxx - xxxxx - - xxx -
Active test Diagnostic Test Mode in which CONSULT-III drives
some actuators apart from the ECMs and also shifts
some parameters in a specified range. x-xx-xx-xx-x- - - -
Function test This mode can show results of self-diagnosis of ECU
with either “OK” or “NG”. For engines, more practical
tests regarding sensors/switches and/or actuators
are available. xxxxx - - - x
-------
DTC & SRT confir-
mation The results of SRT (System Readiness Test) and the
self-diagnosis status/result can be confirmed.
x-x-----x-------
DTC work support The operating condition to confirm Diagnosis Trouble
Codes can be selected. xxx-----x-------
ECM/ECU part num-
ber ECM/ECU part number can be read.
xxxx - - x - xxxxx - xx
ECU discriminated
No. Classification number of a replacement ECU can be
read to prevent an incorrect ECU from being in-
stalled.
----x-----------
Revision: March 2010
2008 QX56

GW-2
< PRECAUTION >
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004884108
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:0000000004881261
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

HA-2
CONDENSER ....................................................44
Removal and Installation for Condenser ................44
AMBIENT SENSOR ........................................ ...45
Removal and Installation ..................................... ...45
REFRIGERANT PRESSURE SENSOR ............46
Removal and Installation for Refrigerant Pressure
Sensor ................................................................. ...
46
EXPANSION VALVE .........................................47
Removal and Installation for Front Expansion
Valve .................................................................... ...
47
SERVICE DATA AND SPECIFICATIONS
(SDS) .......... ................................. ...............
48
SERVICE DATA AND SPECIFICATIONS
(SDS) .............................................................. ...
48
Service Data and Specification (SDS) ....................48
Revision: March 2010 2008 QX56

PRECAUTIONSHA-3
< PRECAUTION >
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PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000004884163
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty 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 inoper ative, 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 unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the SR section.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied 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 Un it or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or el ectric 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 minutes before performing any service.
Precaution Necessary for Steering Wheel Rotation After Battery Disconnect
INFOID:0000000004884164
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 disconnecti ng 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 power 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