Electrical Wiring INFINITI QX4 2001 Factory Owner's Guide

The second method is to put the suspect component into a freezer
long enough for any water to freeze. Reinstall the part into the car
and check for the reoccurrence of the incident. If it occurs, repair
or replace the component.
SGI844
WATER INTRUSIONNBGI0004S0205The incident may occur only during high humidity or in rainy/snowy
weather. In such cases the incident could be caused by water
intrusion on an electrical part. This can be simulated by soaking the
car or running it through a car wash.
Do not spray water directly on any electrical components.
SGI845
ELECTRICAL LOADNBGI0004S0206The incident may be electrical load sensitive. Perform diagnosis
with all accessories (including A/C, rear window defogger, radio,
fog lamps) turned on.
COLD OR HOT START UPNBGI0004S0207On some occasions an electrical incident may occur only when the
car is started cold. Or it may occur when the car is restarted hot
shortly after being turned off. In these cases you may have to keep
the car overnight to make a proper diagnosis.
Circuit InspectionNBGI0004S03INTRODUCTIONNBGI0004S0302In general, testing electrical circuits is an easy task if it is
approached in a logical and organized method. Before beginning
it is important to have all available information on the system to be
tested. Also, get a thorough understanding of system operation.
Then you will be able to use the appropriate equipment and follow
the correct test procedure.
You may have to simulate vehicle vibrations while testing electrical
components.Gently shakethe wiring harness or electrical com-
ponent to do this.
OPEN A circuit is open when there is no continuity through a section of
the circuit.
SHORT There are two types of shorts.
ISHORT CIRCUIT When a circuit contacts another circuit
and causes the normal resistance to
change.
ISHORT TO GROUND When a circuit contacts a ground
source and grounds the circuit.
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HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT
Incident Simulation Tests (Cont'd)
GI-27

ohmmeter, contact by a single strand of wire will give reading of 0
ohms. This would indicate a good circuit. When the circuit operates,
this single strand of wire is not able to carry the current. The single
strand will have a high resistance to the current. This will be picked
up as a slight voltage drop.
Unwanted resistance can be caused by many situations as follows:
IUndersized wiring (single strand example)
ICorrosion on switch contacts
ILoose wire connections or splices.
If repairs are needed always use wire that is of the same or larger
gauge.
Measuring Voltage Drop Ð Accumulated Method
1) Connect the voltmeter across the connector or part of the cir-
cuit you want to check. The positive lead of the voltmeter
should be closer to power and the negative lead closer to
ground.
2) Operate the circuit.
3) The voltmeter will indicate how many volts are being used to
ªpushº current through that part of the circuit.
Note in the illustration that there is an excessive 4.1 volt drop
between the battery and the bulb.
SGI974
Measuring Voltage Drop Ð Step by Step
The step by step method is most useful for isolating excessive
drops in low voltage systems (such as those in ªComputer Con-
trolled Systemsº).
Circuits in the ªComputer Controlled Systemº operate on very low
amperage.
The (Computer Controlled) system operations can be adversely
affected by any variation in resistance in the system. Such resis-
tance variation may be caused by poor connection, improper
installation, improper wire gauge or corrosion.
The step by step voltage drop test can identify a component or wire
with too much resistance.
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HOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENT
Circuit Inspection (Cont'd)
GI-31

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBHA0001The 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 passenger 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 steer-
ing wheel), front passenger 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 front 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 components 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 per-
sonal 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 Working with HFC-134a
(R-134a)
NBHA0002WARNING:
ICFC-12 (R-12) refrigerant and HFC-134a (R-134a) refrigerant are not compatible. If the refrigerants
are mixed and compressor failure is likely to occur, refer to ªCONTAMINATED REFRIGERANTº
below. To determine the purity of HFC-134a (R-134a) in the vehicle and recovery tank, use Refrig-
erant Recovery/Recycling Recharging equipment (ACR4) (J-39500-INF) and Refrigerant Identifier.
IUse only specified lubricant for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) compo-
nents. If lubricant other than that specified is used, compressor failure is likely to occur.
IThe specified HFC-134a (R-134a) lubricant rapidly absorbs moisture from the atmosphere. The fol-
lowing handling precautions must be observed:
a) When removing refrigerant components from a vehicle, immediately cap (seal) the component to
minimize the entry of moisture from the atmosphere.
b) When installing refrigerant components to a vehicle, do not remove the caps (unseal) until just
before connecting the components. Connect all refrigerant loop components as quickly as pos-
sible to minimize the entry of moisture into system.
c) Only use the specified lubricant from a sealed container. Immediately reseal containers of lubri-
cant. Without proper sealing, lubricant will become moisture saturated and should not be used.
d) Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and
throat. Remove R-134a from the A/C system, using certified service equipment meeting require-
ments of SAE J2210 (R-134a recycling equipment), or J2209 (R-134a recovery equipment). If acci-
dental system discharge occurs, ventilate work area before resuming service. Additional health and
safety information may be obtained from refrigerant and lubricant manufacturers.
e) Do not allow lubricant (Nissan A/C System Oil Type S) to come in contact with styrofoam parts.
Damage may result.
CONTAMINATED REFRIGERANTNBHA0002S01If a refrigerant other than pure R-134a is identified in a vehicle, your options are:
IExplain to the customer that environmental regulations prohibit the release of contaminated refrigerant into
the atmosphere.
IExplain that recovery of the contaminated refrigerant could damage your service equipment and refriger-
ant supply.
PRECAUTIONS
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
HA-2

Wiring Diagrams and Trouble DiagnosesNBHA0007When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-10, ªWiring Diagram Ð POWER к for power distribution
circuit
When you perform trouble diagnoses, refer to the following:
IGI-34, ªHOW TO FOLLOW TROUBLE DIAGNOSESº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR
AN ELECTRICAL INCIDENTºGI
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PRECAUTIONS
Wiring Diagrams and Trouble Diagnoses
HA-9

E
ECM input/output signal ...............................EC-127
ECTS - Wiring diagram ........................EC-171, 189
Electric sun roof ............................................EL-173
Electrical diagnoses.........................................GI-24
Electrical ignition system ................................EC-30
Electrical unit ................................................Foldout
Electrical units location .................................EL-436
Engine compartment .......................................BT-58
Engine control circuit diagram........................EC-24
Engine control component parts
location .......................................................EC-20
Engine control module (ECM) ......................EC-444
Engine control system diagram and
chart ............................................................EC-25
Engine coolant temperature sensor
(ECTS) ..............................................EC-169, 187
Engine fail-safe system ................................EC-117
Engine oil filter replacement ..........................MA-18
Engine oil precautions .......................................GI-8
Engine oil replacement ..................................MA-18
Engine outer component parts ......................EM-10
Engine removal ..............................................EM-57
Engine room - See Engine
compartment................................................BT-58
Engine serial number ......................................GI-43
EVAP canister.................................................EC-33
EVAP canister purge volume control
solenoid valve.............................EC-32, 367, 541
EVAP canister vent control
valve .........................................EC-374, 553, 573
EVAP control system (small leak)
diagnosis ..................................EC-352, 394, 526
EVAP control system pressure sensor.........EC-381
EVAP control system purge flow moni-
toring diagnosis.........................................EC-561
EVAP vapor lines inspection ..........................MA-20
Evaporative emission (EVAP) system ............EC-32
Exhaust system ................................................FE-8
Exhaust system inspection ............................MA-21
Exterior ............................................................BT-35
F
4LO indicator lamp........................................TF-104
4WD shift indicator lamp.................................TF-98
4WD shift switch ............................................TF-111
4WD solenoid valve.......................................TF-111
4WD warning lamp .........................................TF-13
Fan control amp. ............................................HA-98
F/FOG - Wiring diagram .................................EL-72
Final drive disassembly ..................................PD-43
Final drive pre-inspection ...............................PD-43
Final drive removal and installation ...............PD-43
Finisher, interior - See Trim ............................BT-28
F/LID - Wiring diagram .................................EL-180
Fluid temperature sensor (A/T) .....................AT-110Fluids ..............................................................MA-11
Flywheel runout..............................................EM-70
FO2H-L - Wiring diagram .............................EC-243
FO2H-R - Wiring diagram ............................EC-242
Fog lamp, front................................................EL-70
Fog lamp, front, removal and
installation ...................................................BT-12
Forward clutch ...............................................AT-320
F/PUMP - Wiring diagram ............................EC-627
Freeze frame data ..........................................EC-60
FRO2LH - Wiring diagram ...........EC-197, 223, 235
FRO2RH - Wiring diagram...........EC-196, 222, 234
Front axle..........................................................AX-2
Front bumper ..................................................BT-12
Front case (Transfer) ....................................TF-133
Front combination lamp removal and
installation ...................................................BT-12
Front disc brake .............................................BR-22
Front door .......................................................BT-18
Front drive shaft (Transfer) ...........................TF-125
Front final drive disassembly (4WD) ..............PD-18
Front final drive pre-inspection (4WD) ...........PD-18
Front final drive removal and installa-
tion (4WD)...................................................PD-18
Front fog lamp.................................................EL-70
Front fog lamp removal and installation .........BT-12
Front heated oxygen sensor (HO2S)
(Left bank) ................EC-192, 202, 210, 218, 231
Front heated oxygen sensor (HO2S)
(Right bank) .............EC-192, 202, 210, 218, 231
Front heated oxygen sensor heater
(Left bank).................................................EC-240
Front heated oxygen sensor heater
(Right bank) ..............................................EC-240
Front revolution sensor (Transfer) ................TF-112
Front seat ........................................................BT-41
Front seat belt ..................................................RS-4
Front suspension ..............................................SU-2
Front washer .................................................EL-136
Front wiper ....................................................EL-136
Fuel cut control (at no load & high
engine speed) .............................................EC-32
Fuel filler lid.....................................................BT-15
Fuel filter replacement ...................................MA-16
Fuel gauge ......................................................EL-94
Fuel injection system (Left bank) .........EC-294, 302
Fuel injection system (Right bank) ......EC-294, 302
Fuel lid opener, electric.................................EL-180
Fuel line inspection ........................................MA-16
Fuel precautions ................................................GI-8
Fuel pressure check .......................................EC-39
Fuel pressure regulator ..................................EC-40
Fuel pressure release ....................................EC-39
Fuel pump ....................................................EC-625
Fuel system ......................................................FE-4
Fuel tank temperature sensor ......................EC-309
Fuel tank vacuum relief valve ........................EC-33
FUELLH - Wiring diagram....................EC-297, 305
FUELRH - Wiring diagram ...................EC-296, 304
Fuse ................................................................EL-16
Fuse block ....................................................Foldout
ALPHABETICAL INDEX
IDX-4

Fusible link ......................................................EL-16
G
Garage jack and safety stand .........................GI-46
Gauges............................................................EL-94
Generator - See Alternator .............................SC-28
Generic scan tool (GST) ................................EC-95
Glass ...............................................................BT-18
Glass hatch opener, electric .........................EL-178
Grease ............................................................MA-11
Ground distribution..........................................EL-17
H
Harness connector ............................................EL-5
Harness connector inspection .........................GI-21
Harness layout ..............................................EL-440
Hazard warning lamp ......................................EL-75
Headlamp ........................................................EL-31
Headlamp aiming control ................................EL-59
Headlining - See Roof trim .............................BT-32
Heated seat .......................................BT-43, EL-183
Height (Dimensions) ........................................GI-43
HFC134a (R134a) system precaution .............HA-2
HFC134a (R134a) system service
procedure ..................................................HA-144
HFC134a (R134a) system service tools ........HA-11
HFC134a system service equipment
precaution .....................................................HA-7
High clutch.....................................................AT-317
H/LAMP - Wiring diagram ...............................EL-36
Hood................................................................BT-12
Horn ..............................................................EL-147
HORN - Wiring diagram................................EL-147
How to erase DTC for OBD system...............EC-72
HSEAT - Wiring diagram...............................EL-183
I
IACV-AAC valve ...........................................EC-422
IATS - Wiring diagram ..................................EC-166
Identification .....................................................HA-4
Identification plate............................................GI-42
Idle air control valve (IACV) .........................EC-422
Idle mixture ratio.............................................EC-43
Idle speed .......................................................EC-43
IGN/SG - Wiring diagram .............................EC-501
Ignition control system .................................EC-499
Ignition timing .................................................EC-43
ILL - Wiring diagram .......................................EL-83
Illumination ......................................................EL-80
In vehicle sensor ..........................................HA-132
INFINITI COMMUNICATOR..........................EL-348
Infiniti communicator (IVCS) .........................EL-348
INJECT - Wiring diagram .............................EC-617
Injector ..........................................................EC-616Injector removal and installation ....................EC-41
Instrument panel .............................................BT-21
INT/L - Wiring diagram....................................EL-91
Intake air temparature sensor ......................EC-164
Intake door control linkage adjustment ..........HA-94
Intake door motor ...........................................HA-87
Intake manifold...............................................EM-12
Intake sensor ................................................HA-139
Integrated homelink transmitter ....................EL-325
Interior .............................................................BT-28
Interior lamp ....................................................EL-88
Interior lamp on-off control ..............................EL-89
Internal gear (Transfer) .................................TF-134
IVC-L - Wiring diagram.................................EC-453
IVC-R - Wiring diagram ................................EC-453
IVCS - Wiring diagram ..................................EL-359
IVCS-L - Wiring diagram ..............................EC-485
IVCS-R - Wiring diagram .............................EC-485
IVIS (Infiniti vehicle immobilizer
system) ......................................................EL-328
IVIS (Infiniti vehicle immobilizer sys-
tem) precautions ............................................GI-3
J
Jacking points ..................................................GI-45
Journal bearing assembly (propeller
shaft) .............................................................PD-9
Journal bearing disassembly (propeller
shaft) .............................................................PD-8
Junction box (J/B).........................................Foldout
K
Keyless entry system - See Multi-re-
mote control system ..................................EL-270
Knock sensor (KS) .......................................EC-328
Knuckle spindle ................................................AX-9
KS - Wiring diagram .....................................EC-330
L
Length (Dimensions) .......................................GI-43
License lamp ...................................................EL-61
Lifting points ....................................................GI-47
Limited slip diff. adjustment ............................PD-50
Limited slip diff. assembly ..............................PD-51
Limited slip diff. disassembly..........................PD-48
Limited slip diff. inspection .............................PD-49
Line pressure solenoid valve ........AT-147, 161, 167
Line pressure switch (Transfer) .....................TF-111
Line pressure test (A/T) ..................................AT-62
Liquid gasket application .................................EM-3
LOAD - Wiring diagram ................................EC-643
Location of electrical units ............................EL-436
Lock, door .......................................................BT-18
Low and reverse brake .................................AT-324
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ALPHABETICAL INDEX
IDX-5

Supplemental Restraint System (SRS) ªAIR
BAGº and ªSEAT BELT PRE-TENSIONERº
NBMA0001The 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 passenger 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 steer-
ing wheel), front passenger 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 components 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 per-
sonal 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
Supplemental Restraint System (SRS) ªAIR BAGº and ªSEAT BELT PRE-TENSIONERº
MA-2

Precautions
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) ªAIR BAGº AND ªSEAT BELT
PRE-TENSIONERº
NBRS0001The 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 passenger for certain types of
collision. The SRS 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 steer-
ing wheel), front passenger 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 components of air bags for a frontal collision).
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 per-
sonal injury caused by unintentional activation of the system.
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.
PRECAUTION FOR SEAT BELT SERVICENBRS0002CAUTION:
IBefore removing the seat belt pre-tensioner assembly, turn the ignition switch off, disconnect both
battery cables and wait at least 3 minutes.
IDo not use electrical test equipment for seat belt pre-tensioner connector.
IAfter replacing or reinstalling seat belt pre-tensioner assembly, or reconnecting seat belt pre-ten-
sioner connector, check the system function. Refer to ªSRS Operation Checkº (RS-38) for details.
IDo not use disassemble buckle or seat belt assembly.
IReplace anchor bolts if they are deformed or worn out.
INever oil tongue and buckle.
IIf any component of seat belt assembly is questionable, do not repair. Replace the whole seat belt
assembly.
IIf webbing is cut, frayed, or damaged, replace seat belt assembly.
IWhen replacing seat belt assembly, use a genuine seat belt assembly.
After A CollisionNBRS0002S01WARNING:
Inspect all seat belt assemblies including retractors and attaching hardware after any collision.
NISSAN recommends that all seat belt assemblies in use during a collision be replaced unless the
collision was minor and the belts show no damage and continue to operate properly. Failure to do so
could result in serious personal injury in an accident. Seat belt assemblies not in use during a colli-
sion should also be replaced if either damage or improper operation is noted. Seat belt pre-tensioner
should be replaced even if the seat belts are not in use during a frontal collision in which the air bags
are deployed.
Replace any seat belt assembly if:
IThe seat belt was in use at the time of a collision (except for minor collisions and the belts, retractors and
buckles show no damage and continue to operate properly).
IThe seat belt was damaged in an accident. (i.e. torn webbing, bent retractor or guide, etc.)
IThe seat belt attaching point was damaged in an accident. Inspect the seat belt attaching area for dam-
age or distortion and repair as necessary before installing a new seat belt assembly.
IAnchor bolts are deformed or worn out.
IThe seat belt pre-tensioner should be replaced even if the seat belts are not in use during the collision in
which the air bags are deployed.
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SEAT BELTS
Precautions
RS-3

Precautions
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) ªAIR BAGº AND ªSEAT BELT
PRE-TENSIONERº
NBRS0005The 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 passenger for certain types of
collision. The SRS 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 steer-
ing wheel), front passenger 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 components of air bags for a frontal collision).
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 per-
sonal injury caused by unintentional activation of the system.
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 SRS ªAIR BAGº AND ªSEAT BELT PRE-TENSIONERº SERVICENBRS0006IDo not use electrical test equipment to check SRS circuits unless instructed to in this Service Manual.
IBefore servicing the SRS, turn ignition switch ªOFFº, disconnect both battery cables and wait at least 3
minutes.
For approximately 3 minutes after the cables are removed, it is still possible for the air bag and seat belt
pre-tensioner to deploy. Therefore, do not work on any SRS connectors or wires until at least 3 minutes
have passed.
IDiagnosis sensor unit must always be installed with their arrow marks ªgº pointing towards the front of
the vehicle for proper operation. Also check diagnosis sensor unit for cracks, deformities or rust before
installation and replace as required.
IThe spiral cable must be aligned with the neutral position since its rotations are limited. Do not attempt to
turn steering wheel or column after removal of steering gear.
IHandle air bag module carefully. Always place driver and passenger air bag modules with the pad side
facing upward and side air bag module (built-in type) standing with the stud bolt side setting bottom.
IConduct self-diagnosis to check entire SRS for proper function after replacing any components.
IAfter air bag inflates, the front instrument panel assembly should be replaced if damaged.
WIRING DIAGRAMS AND TROUBLE DIAGNOSISNBRS0007When you read wiring diagrams, refer to the following:
IGI-11, ªHOW TO READ WIRING DIAGRAMSº
IEL-9, ªPOWER SUPPLY ROUTINGº for power distribution circuit
When you perform trouble diagnosis, refer to the following:
IGI-35, ªHOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSESº
IGI-24, ªHOW TO PERFORM EFFICIENT DIAGNOSIS FOR AN ELECTRICAL INCIDENTº
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
Precautions
RS-10

Trouble Diagnoses Introduction=NBRS0040CAUTION:
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.
IDo not attempt to repair, splice or modify the SRS wiring harness. If the harness is damaged,
replace it with a new one.
IKeep ground portion clean.
DIAGNOSIS FUNCTIONNBRS0040S01The SRS self-diagnosis results can be read by using ªAIR BAGº warning lamp and/or CONSULT-II. The read-
ing of these results is accomplished using one of two modes Ð ªUser modeº and ªDiagnosis modeº.
The User mode is exclusively prepared for the customer (driver). This mode warns the driver of a system
malfunction through the operation of the ªAIR BAGº warning lamp.
The Diagnosis mode allows the technician to locate and inspect the malfunctioning part.
The mode applications for the ªAIR BAGº warning lamp and CONSULT-II are as follows:
User mode Diagnosis mode Display type
ªAIR BAGº warning lamp X X ON-OFF operation
CONSULT-II Ð X Monitoring
NOTE:
Seat belt pre-tensioner malfunction is indicated by ªAIR BAGº warning lamp.
DIAGNOSIS MODE FOR CONSULT-IINBRS0040S02IªSELF-DIAG [CURRENT]º
A current Self-diagnosis result (also indicated by the number of warning lamp flashes in the Diagnosis
mode) is displayed on the CONSULT-II screen in real time. This refers to a malfunctioning part requiring
repairs.
IªSELF-DIAG [PAST]º
Diagnosis results previously stored in the memory are displayed on the CONSULT-II screen. The stored
results are not erased until memory erasing is executed.
IªTROUBLE DIAG RECORDº
With TROUBLE DIAG RECORD, diagnosis results previously erased by a reset operation can be displayed
on the CONSULT-II screen.
IªECU DISCRIMINATED NO.º
The diagnosis sensor unit for each vehicle model is assigned with its own, individual classification num-
ber. This number will be displayed on the CONSULT-II screen, as shown below. When replacing the diag-
nosis sensor unit, refer to the part number for the compatibility. After installation, replacement with a cor-
rect unit can be checked by confirming this classification number on the CONSULT-II screen.
SRS851
For INFINITI QX4, the diagnosis sensor unit classification numbers assigned is A540.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
BT
HA
SC
EL
IDX
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
Trouble Diagnoses Introduction
RS-29