2001 INFINITI QX4 Ac system

PrecautionsNBGI0001Observe the following precautions to ensure safe and proper
servicing. These precautions are not described in each indi-
vidual section.
SGI646
PRECAUTIONS FOR SUPPLEMENTAL RESTRAINT
SYSTEM (SRS) ªAIR BAGº AND ªSEAT BELT
PRE-TENSIONERº
NBGI0001S01The Supplemental Restraint System such as ªAIR BAGº and ªSEAT
BELT PRE-TENSIONERº used along with a seat belt, helps to
reduce the risk or severity of injury to the driver and front passen-
ger for certain types of collision. The SRS system composition
which is available to INFINITI QX4 is as follows:
IFor a frontal collision
The Supplemental Restraint System consists of driver air bag
module (located in the center of the steering wheel), front pas-
senger air bag module (located on the instrument panel on
passenger side), seat belt pre-tensioners, a diagnosis sensor
unit, warning lamp, wiring harness and spiral cable.
IFor a side collision
The Supplemental Restraint System consists of side air bag
module (located in the outer side of front seat), satellite sensor,
diagnosis sensor unit (one of components of air bags for a
frontal collision), wiring harness, warning lamp (one of compo-
nents of air bags for a frontal collision).
Information necessary to service the system safely is included in
theRS sectionof this Service Manual.
WARNING:
ITo avoid rendering the SRS inoperative, 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 INFINITI
dealer.
IImproper maintenance, including incorrect removal and
installation of the SRS, can lead to personal injury caused
by unintentional activation of the system. For removal of
Spiral Cable and Air Bag Module, see the RS section.
IDo not use electrical test equipment on any circuit related
to the SRS unless instructed to in this Service Manual.
Spiral cable and wiring harnesses covered with yellow
insulation tape either just before the harness connectors
or for the complete harness are related to the SRS.
PRECAUTIONS FOR IVIS (INFINITI VEHICLE
IMMOBILIZER SYSTEM Ð NATS)
NBGI0001S08IVIS (NATS) will immobilize the engine if someone tries to start it
without the registered key of IVIS (NATS).
Both of the originally supplied ignition key IDs have been IVIS
(NATS) registered.
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PRECAUTIONS
Precautions
GI-3

The security indicator is located on the instrument panel. The indi-
cator blinks when the ignition switch is in OFF or ACC position.
Therefore, IVIS (NATS) warns outsiders that the vehicle is
equipped with the anti-theft system.
IWhen IVIS (NATS) detects trouble, the security indicator lamp
lights up while ignition switch is in ON position.
This lighting up indicates that the anti-theft is not functioning,
so prompt service is required.
IWhen servicing IVIS (NATS) (trouble diagnoses, system initial-
ization and additional registration of other IVIS (NATS) ignition
key IDs), CONSULT-II hardware and CONSULT-II IVIS (NATS)
software is necessary.
Regarding the procedures of IVIS (NATS) initialization and
IVIS (NATS) ignition key ID registration, refer to CONSULT-II
operation manual, IVIS/NVIS.
Therefore, CONSULT-II IVIS (NATS) software (program card
and operation manual) must be kept strictly confidential to
maintain the integrity of the anti-theft function.
IWhen servicing IVIS (NATS) (trouble diagnoses, system initial-
ization and additional registration of other IVIS (NATS) ignition
key IDs), it may be necessary to re-register original key iden-
tification. Therefore, be sure to receive all keys from vehicle
owner.
A maximum of five key IDs can be registered into IVIS (NATS).
IWhen failing to start the engine first time using the key of IVIS
(NATS) (for example, when interference is caused by another
IVIS (NATS) key, an automated full road device or automated
payment device on the key ring), restart as follows.
a) Leave the ignition switch in ON position for approximately 5
seconds.
b) Turn ignition switch to OFF or LOCK position and wait approxi-
mately 5 seconds.
c) Repeat step 1 and 2.
d) Restart the engine while holding the device (which may have
caused the interference) separate from the registered NATS
key. If the no start condition re-occurs, NISSAN recommends
placing the registered IVIS (NATS) key on a separate key ring
to avoid interference from other devices.
PRECAUTIONS FOR INFINITI COMMUNICATOR (IVCS)NBGI0001S09The purpose of INFINITI Communicator is to increase security for
the vehicle owner by providing a convenient way to contact the
most appropriate emergency assistance provider during an emer-
gency.
Improper operation of the system may result in a police response.
The theft warning system also activates INFINITI Communicator.
For details, refer to INFINITI Communicator (IVCS) in the EL sec-
tion.
PRECAUTIONS
Precautions (Cont'd)
GI-4

IClean all disassembled parts in the designated liquid or solvent
prior to inspection or assembly.
IReplace oil seals, gaskets, packings, O-rings, locking washers,
cotter pins, self-locking nuts, etc. with new ones.
IReplace inner and outer races of tapered roller bearings and
needle bearings as a set.
IArrange the disassembled parts in accordance with their
assembled locations and sequence.
IDo not touch the terminals of electrical components which use
microcomputers (such as ECMs).
Static electricity may damage internal electronic components.
IAfter disconnecting vacuum or air hoses, attach a tag to indi-
cate the proper connection.
IUse only the fluids and lubricants specified in this manual.
IUse approved bonding agent, sealants or their equivalents
when required.
IUse tools and recommended special tools where specified for
safe and efficient service repairs.
IWhen repairing the fuel, oil, water, vacuum or exhaust
systems, check all affected lines for leaks.
IDispose of drained oil or the solvent used for cleaning parts in
an appropriate manner.
WARNING:
To prevent ECM from storing the diagnostic trouble codes, do
not carelessly disconnect the harness connectors which are
related to the engine control system and TCM (Transmission
Control Module) system. The connectors should be discon-
nected only when working according to the WORK FLOW of
TROUBLE DIAGNOSES in EC and AT sections.
SGI787
PRECAUTIONS FOR MULTIPORT FUEL INJECTION
SYSTEM OR ENGINE CONTROL SYSTEM
NBGI0001S03IBefore connecting or disconnecting any harness connector for
the multiport fuel injection system or ECM (Engine Control
Module):
Turn ignition switch to OFF position.
Disconnect negative battery terminal.
Otherwise, there may be damage to ECM.
IBefore disconnecting pressurized fuel line from fuel pump to
injectors, be sure to release fuel pressure.
IBe careful not to jar components such as ECM and mass air
flow sensor.
PRECAUTIONS FOR THREE WAY CATALYSTNBGI0001S04If a large amount of unburned fuel flows into the catalyst, the cata-
lyst temperature will be excessively high. To prevent this, follow the
instructions below:
IUse unleaded gasoline only. Leaded gasoline will seriously
damage the three way catalyst.
IWhen checking for ignition spark or measuring engine
compression, make tests quickly and only when necessary.
IDo not run engine when the fuel tank level is low, otherwise the
engine may misfire causing damage to the catalyst.
PRECAUTIONS
Precautions (Cont'd)
GI-6

PRECAUTIONS FOR ENGINE OILSNBGI0001S05Prolonged and repeated contact with used engine oil may cause
skin cancer. Try to avoid direct skin contact with used oil.
If skin contact is made, wash thoroughly with soap or hand cleaner
as soon as possible.
Health Protection PrecautionsNBGI0001S0501IAvoid prolonged and repeated contact with oils, particularly
used engine oils.
IWear protective clothing, including impervious gloves where
practicable.
IDo not put oily rags in pockets.
IAvoid contaminating clothes, particularly underpants, with oil.
IHeavily soiled clothing and oil-impregnated footwear should
not be worn. Overalls must be cleaned regularly.
IFirst Aid treatment should be obtained immediately for open
cuts and wounds.
IUse barrier creams, applying them before each work period, to
help the removal of oil from the skin.
IWash with soap and water to ensure all oil is removed (skin
cleansers and nail brushes will help). Preparations containing
lanolin replace the natural skin oils which have been removed.
IDo not use gasoline, kerosine, diesel fuel, gas oil, thinners or
solvents for cleaning skin.
IIf skin disorders develop, obtain medical advice without delay.
IWhere practicable, degrease components prior to handling.
IWhere there is a risk of eye contact, eye protection should be
worn, for example, chemical goggles or face shields; in addi-
tion an eye wash facility should be provided.
Environmental Protection PrecautionsNBGI0001S0502Burning used engine oil in small space heaters or boilers can be
recommended only for units of approved design. The heating sys-
tem must meet the requirements of HM Inspectorate of Pollution for
small burners of less than 0.4 MW. If in doubt check with the
appropriate local authority and/or manufacturer of the approved
appliance.
Dispose of used oil and used oil filters through authorized waste
disposal contractors to licensed waste disposal sites, or to the
waste oil reclamation trade. If in doubt, contact the local authority
for advice on disposal facilities.
It is illegal to pour used oil on to the ground, down sewers or drains,
or into water courses.
The regulations concerning pollution vary between regions.
PRECAUTIONS FOR FUELNBGI0001S06Use unleaded gasoline with an octane rating of at least 87 AKI
(Anti-Knock Index) number (research octane number 91).
CAUTION:
Do not use leaded gasoline. Using leaded gasoline will dam-
age the three way catalyst.
Using a fuel other than that specified could adversely affect
the emission control devices and systems, and could also
affect the warranty coverage validity.
PRECAUTIONS FOR AIR CONDITIONINGNBGI0001S07Use an approved refrigerant recovery unit any time the air condi-
tioning system must be discharged. Refer to HA-144, ªHFC-134a
(R-134a) Service Procedureº for specific instructions.
PRECAUTIONS
Precautions (Cont'd)
GI-8

NBGI0002
IThe captionsWARNINGandCAUTIONwarn you of steps that must be followed to prevent personal injury
and/or damage to some part of the vehicle.
WARNINGindicates the possibility of personal injury if instructions are not followed.
CAUTIONindicates the possibility of component damage if instructions are not followed.
BOLD TYPED STATEMENTSexceptWARNINGandCAUTIONgive you helpful information.
IALPHABETICAL INDEXis provided at the end of this manual so that you can rapidly find the item and
page you are searching for.
IA QUICK REFERENCE INDEX, a black tab (e.g.
) is provided on the first page. You can quickly find
the first page of each section by mating it to the section's black tab.
ITHE CONTENTSare listed on the first page of each section.
ITHE TITLEis indicated on the upper portion of each page and shows the part or system.
ITHE PAGE NUMBERof each section consists of two letters which designate the particular section and a
number (e.g. ªBR-5º).
ITHE LARGE ILLUSTRATIONSare exploded views (See below.) and contain tightening torques, lubrica-
tion points, section number of thePARTS CATALOG(e.g. SEC. 440) and other information necessary to
perform repairs.
The illustrations should be used in reference to service matters only. When ordering parts, refer to the
appropriatePARTS CATALOG.
SBR364AC
ITHE SMALL ILLUSTRATIONSshow the important steps such as inspection, use of special tools, knacks
of work and hidden or tricky steps which are not shown in the previous large illustrations.
Assembly, inspection and adjustment procedures for the complicated units such as the automatic transaxle
or transmission, etc. are presented in a step-by-step format where necessary.
ITheUNITSgiven in this manual are primarily expressed as the SI UNIT (International System of Unit),
and alternatively expressed in the metric system and in the yard/pound system.
ªExampleº
Tightening torque:
59 - 78 N´m (6.0 - 8.0 kg-m, 43 - 58 ft-lb)
ITROUBLE DIAGNOSESare included in sections dealing with complicated components.
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HOW TO USE THIS MANUAL
GI-9

Description=NBGI0003S02
Number Item Description
1 Power conditionIThis shows the condition when the system receives battery positive voltage (can be oper-
ated).
2 Fusible linkIThe double line shows that this is a fusible link.
IThe open circle shows current flow in, and the shaded circle shows current flow out.
3Fusible link/fuse loca-
tionIThis shows the location of the fusible link or fuse in the fusible link or fuse box. For
arrangement, refer to EL-10, ªPOWER SUPPLY ROUTINGº.
4 FuseIThe single line shows that this is a fuse.
IThe open circle shows current flow in, and the shaded circle shows current flow out.
5 Current ratingIThis shows the current rating of the fusible link or fuse.
6 ConnectorsIThis shows that connector E3 is female and connector M1 is male.
IThe G/R wire is located in the 1A terminal of both connectors.
ITerminal number with an alphabet (1A, 5B, etc.) indicates that the connector is SMJ con-
nector. Refer to GI-19.
7 Optional spliceIThe open circle shows that the splice is optional depending on vehicle application.
8 SpliceIThe shaded circle shows that the splice is always on the vehicle.
9 Page crossingIThis arrow shows that the circuit continues to an adjacent page.
IThe A will match with the A on the preceding or next page.
10 Common connectorIThe dotted lines between terminals show that these terminals are part of the same con-
nector.
11 Option abbreviationIThis shows that the circuit is optional depending on vehicle application.
12 RelayIThis shows an internal representation of the relay. For details, refer to EL-7, ªSTANDARD-
IZED RELAYº.
13 ConnectorsIThis shows that the connector is connected to the body or a terminal with bolt or nut.
14 Wire colorIThis shows a code for the color of the wire.
B = Black
W = White
R = Red
G = Green
L = Blue
Y = Yellow
LG = Light GreenBR = Brown
OR = Orange
P = Pink
PU = Purple
GY = Gray
SB = Sky Blue
CH = Dark Brown
DG = Dark Green
When the wire color is striped, the base color is given first, followed by the stripe color as
shown below:
Example: L/W = Blue with White Stripe
15 Option descriptionIThis shows a description of the option abbreviation used on the page.
16 SwitchIThis shows that continuity exists between terminals 1 and 2 when the switch is in the A
position. Continuity exists between terminals 1 and 3 when the switch is in the B position.
17 Assembly partsIConnector terminal in component shows that it is a harness incorporated assembly.
18 Cell codeIThis identifies each page of the wiring diagram by section, system and wiring diagram
page number.
19 Current flow arrowIArrow indicates electric current flow, especially where the direction of standard flow (verti-
cally downward or horizontally from left to right) is difficult to follow.
IA double arrow ª
º shows that current can flow in either direction depending on cir-
cuit operation.
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HOW TO READ WIRING DIAGRAMS
Description
GI-13

Number Item Description
20 System branchIThis shows that the system branches to another system identified by cell code (section
and system).
21 Page crossingIThis arrow shows that the circuit continues to another page identified by cell code.
IThe C will match with the C on another page within the system other than the next or pre-
ceding pages.
22 Shielded lineIThe line enclosed by broken line circle shows shield wire.
23Component box in
wave lineIThis shows that another part of the component is also shown on another page (indicated
by wave line) within the system.
24 Component nameIThis shows the name of a component.
25 Connector numberIThis shows the connector number.
IThe letter shows which harness the connector is located in.
IExample:M: main harness. For detail and to locate the connector, refer to EL-442, ªMain
Harnessº. A coordinate grid is included for complex harnesses to aid in locating connec-
tors.
26 Ground (GND)IThe line spliced and grounded under wire color shows that ground line is spliced at the
grounded connector.
27 Ground (GND)IThis shows the ground connection.
28 Connector viewsIThis area shows the connector faces of the components in the wiring diagram on the
page.
29 Common componentIConnectors enclosed in broken line show that these connectors belong to the same com-
ponent.
30 Connector colorIThis shows a code for the color of the connector. For code meaning, refer to wire color
codes, Number 14 of this chart.
31Fusible link and fuse
boxIThis shows the arrangement of fusible link(s) and fuse(s), used for connector views of
ªPOWER SUPPLY ROUTINGº in EL section.
The open square shows current flow in, and the shaded square shows current flow out.
32 Reference areaIThis shows that more information on the Super Multiple Junction (SMJ), Electrical Units
etc., exists at the end of the manual. Refer to GI-19 for details.
HOW TO READ WIRING DIAGRAMS
Description (Cont'd)
GI-14

SGI862-A
DETECTABLE LINES AND NON-DETECTABLE LINESNBGI0003S0203In some wiring diagrams, two kinds of lines, representing wires,
with different weight are used.
IA line with regular weight (wider line) represents a ªdetectable
line for DTC (Diagnostic Trouble Code)º. A ªdetectable line for
DTCº is a circuit in which ECM (Engine Control Module) can
detect its malfunctions with the on board diagnostic system.
IA line with less weight (thinner line) represents a ªnon-detect-
able line for DTCº. A ªnon-detectable line for DTCº is a circuit
in which ECM cannot detect its malfunctions with the on board
diagnostic system.
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HOW TO READ WIRING DIAGRAMS
Description (Cont'd)
GI-17