2001 INFINITI QX4 Electrical

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

HFC-134a (R-134a) Service Tools and
Equipment
=NBHA0009Never mix HFC-134a refrigerant and/or its specified lubricant with CFC-12 (R-12) refrigerant and/or its lubri-
cant.
Separate and non-interchangeable service equipment must be used for handling each type of refrigerant/
lubricant.
Refrigerant container fittings, service hose fittings and service equipment fittings (equipment which handles
refrigerant and/or lubricant) are different between CFC-12 (R-12) and HFC-134a (R-134a). This is to avoid
mixed use of the refrigerants/lubricant.
Adapters that convert one size fitting to another must never be used: refrigerant/lubricant contamination will
occur and compressor failure will result.
Tool number
(Kent-Moore No.)
Tool nameDescription
HFC-134a (R-134a)
refrigerant
NT196
Container color: Light blue
Container marking: HFC-134a (R-134a)
Fitting size: Thread size
ILarge container 1/2²-16 ACME
KLH00-PAGS0
(Ð)
Nissan A/C System Oil
Type S
NT197
Type: Poly alkylene glycol oil (PAG), type S
Application: HFC-134a (R-134a) swash plate (pis-
ton) compressors (Nissan only)
Lubricity: 40 m(1.4 US fl oz, 1.4 Imp fl oz)
(J-39500-INF)
Recovery/Recycling
Recharging equipment
(ACR4)
NT195
Function: Refrigerant Recovery and Recycling and
Recharging
(J-41995)
Electrical leak detector
AHA281A
Power supply:
IDC 12V (Cigarette lighter)
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PREPARATION
HFC-134a (R-134a) Service Tools and Equipment
HA-11

RHA441GA
Transmission Data and Transmission OrderNBHA0014S0802Amplifier data is transmitted consecutively to each of the door motors following the form shown in figure below.
Start: Initial compulsory signal sent to each of the door motors.
Address: Data sent from the auto amplifier is selected according to data-based decisions made by the air mix
door motor and mode door motor.
If the addresses are identical, the opening angle data and error check signals are received by the door motor
LCUs. The LCUs then make the appropriate error decision. If the opening angle data is normal, door control
begins.
If an error exists, the received data is rejected and corrected data received. Finally, door control is based upon
the corrected opening angle data.
Opening angle: Data that shows the indicated door opening angle of each door motor.
Error check: Procedure by which sent and received data is checked for errors. Error data is then compiled.
The error check prevents corrupted data from being used by the air mix door motor and mode door motor.
Error data can be related to the following problems.
IAbnormal electrical frequency
IPoor electrical connections
ISignal leakage from transmission lines
ISignal level fluctuation
Stop signal: At the end of each transmission, a stop operation, in-operation, or internal problem message is
delivered to the auto amplifier. This completes one data transmission and control cycle.
RHA442G
Air Mix Door Control (Automatic Temperature Control)NBHA0014S0803The air mix door is automatically controlled so that in-vehicle temperature is maintained at a predetermined
value by: The temperature setting, ambient temperature, in-vehicle temperature and amount of sunload.
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DESCRIPTION
Features (Cont'd)
HA-21

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