2001 INFINITI QX4 Engine control

GENERAL INFORMATION
SECTION
GI
CONTENTS
PRECAUTIONS...............................................................3
Precautions ..................................................................3
PRECAUTIONS FOR SUPPLEMENTAL
RESTRAINT SYSTEM (SRS)²AIR BAG²AND
²SEAT BELT PRE-TENSIONER²
.................................3
PRECAUTIONS FOR IVIS (INFINITI VEHICLE
IMMOBILIZER SYSTEM - NATS)
.................................3
PRECAUTIONS FOR INFINITI COMMUNICATOR
(IVCS)
.......................................................................4
GENERAL PRECAUTIONS.........................................5
PRECAUTIONS FOR MULTIPORT FUEL
INJECTION SYSTEM OR ENGINE CONTROL
SYSTEM
...................................................................6
PRECAUTIONS FOR THREE WAY CATALYST...........6
PRECAUTIONS FOR HOSES.....................................7
PRECAUTIONS FOR ENGINE OILS...........................8
PRECAUTIONS FOR FUEL........................................8
PRECAUTIONS FOR AIR CONDITIONING..................8
HOW TO USE THIS MANUAL........................................9
HOW TO READ WIRING DIAGRAMS.......................... 11
Sample/Wiring Diagram - EXAMPL - ........................ 11
OPTIONAL SPLICE..................................................12
Description .................................................................13
CONNECTOR SYMBOLS.........................................15
HARNESS INDICATION...........................................16
COMPONENT INDICATION......................................16
SWITCH POSITIONS...............................................16
DETECTABLE LINES AND NON-DETECTABLE
LINES
.....................................................................17
MULTIPLE SWITCH.................................................18
REFERENCE AREA.................................................19
HOW TO CHECK TERMINAL.......................................21
Connector and Terminal Pin Kit.................................21
How to Probe Connectors .........................................21
PROBING FROM HARNESS SIDE............................21
PROBING FROM TERMINAL SIDE...........................21
How to Check Enlarged Contact Spring of
Terminal .....................................................................22
Waterproof Connector Inspection ..............................23
RUBBER SEAL INSPECTION...................................23
WIRE SEAL INSPECTION........................................23Terminal Lock Inspection ...........................................23
HOW TO PERFORM EFFICIENT DIAGNOSIS
FOR AN ELECTRICAL INCIDENT...............................24
Work Flow ..................................................................24
Incident Simulation Tests ...........................................25
INTRODUCTION......................................................25
VEHICLE VIBRATION..............................................25
HEAT SENSITIVE....................................................26
FREEZING..............................................................26
WATER INTRUSION................................................27
ELECTRICAL LOAD.................................................27
COLD OR HOT START UP.......................................27
Circuit Inspection .......................................................27
INTRODUCTION......................................................27
TESTING FOR²OPENS²IN THE CIRCUIT................28
TESTING FOR²SHORTS²IN THE CIRCUIT..............29
GROUND INSPECTION...........................................30
VOLTAGE DROP TESTS..........................................30
CONTROL UNIT CIRCUIT TEST...............................32
HOW TO FOLLOW TROUBLE DIAGNOSIS................34
How to Follow Test Groups in Trouble Diagnosis .....35
Key to Symbols Signifying Measurements or
Procedures.................................................................36
CONSULT-II CHECKING SYSTEM...............................38
Function and System Application ..............................38
Nickel Metal Hydride Battery Replacement...............39
Checking Equipment..................................................39
CONSULT-II Data Link Connector (DLC) Circuit ......40
INSPECTION PROCEDURE.....................................40
IDENTIFICATION INFORMATION................................41
Model Variation ..........................................................41
PREFIX AND SUFFIX DESIGNATIONS.....................41
Identification Number .................................................41
VEHICLE IDENTIFICATION NUMBER
ARRANGEMENT
.....................................................42
IDENTIFICATION PLATE..........................................42
ENGINE SERIAL NUMBER.......................................43
AUTOMATIC TRANSMISSION NUMBER...................43
TRANSFER SERIAL NUMBER..................................43
Dimensions ................................................................43
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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

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

NBGI0006
Function and System ApplicationNBGI0006S01
Diagnostic
test modeFunction ENGINEALL-
MODE
4WDA/T ABSAIR
BAGIVCS*1IVIS
(NATS)*2SMART
EN-
TRANCE
Work sup-
portThis mode enables a
technician to adjust some
devices faster and more
accurate by following the
indications on CONSULT-
II.x x ÐÐÐÐÐÐ
Self-diag-
nostic
resultsSelf-diagnostic results
can be read and erased
quickly.xxxxxxxÐ
Trouble
diagnostic
recordCurrent self-diagnostic
results and all trouble
diagnostic records previ-
ously stored can be read.ÐÐÐÐ x ÐÐÐ
ECU dis-
criminated
No.Classification number of
a replacement ECU can
be read to prevent an
incorrect ECU from being
installed.ÐÐÐÐ x ÐÐÐ
Data monitorInput/Output data in the
ECU (ECM) can be read.x x x xÐxÐÐ
Data monitor
(Spec.)The specified values will
be displayed when an
OK/NG jugement is diffi-
cult for the DATA MONI-
TOR items by Barchart
and Line Graph.x ÐÐÐÐÐÐÐ
DTC work
supportThis mode enables a
technician to set operat-
ing conditions to confirm
self-diagnosis status/
results.ÐÐ x ÐÐÐÐÐ
Active testDiagnostic Test Mode in
which CONSULT-II drives
some actuators apart
from the ECMs and also
shifts some parameters
in a specified range.x ÐÐ x ÐÐÐÐ
ECU (ECM)
part numberECU (ECM) part number
can be read.x x x xÐxÐÐ
Control unit
initializationAll registered ignition key
IDs in NATS components
can be initialized and
new IDs can be regis-
tered.ÐÐÐÐÐÐ x Ð
SRT & DTC
confirmationThe results of SRT (Sys-
tem Readiness Test) and
the self-diagnosis status/
results can be confirmed.x ÐÐÐÐÐÐÐ
Function
checkªRemote door unlock
functionº of IVCS system
can be checked in this
mode.ÐÐÐÐÐ x ÐÐ
CONSULT-II CHECKING SYSTEM
Function and System Application
GI-38

Diagnostic
test modeFunction ENGINEALL-
MODE
4WDA/T ABSAIR
BAGIVCS*1IVIS
(NATS)*2SMART
EN-
TRANCE
Registered
dataDisplay the VIN, etc. data
registered in the IVCS
unit.ÐÐÐÐÐ x ÐÐ
Configura-
tionIThe IVCS system can
be set up in the dem-
onstration mode to
confirm system opera-
tion.
IVarious data related to
both the Communica-
tor Response Center
contract and cellular
provider can be
written/rewritten in this
mode.ÐÐÐÐÐ x ÐÐ
REMO
CONT ID
SET UPA maximum of four IDs
(identifications) can be
registered in the memory
using the remote control-
ler. These IDs can be
also be confirmed and
erased as required.ÐÐÐÐÐÐÐ x
x: Applicable
*1: INFINITI Communicator (IVCS)
*2: IVIS (NATS) [INFINITI Vehicle Immobilizer System (Nissan Anti-Theft System)]
Nickel Metal Hydride Battery ReplacementNBGI0006S06CONSULT-II contains a nickel metal hydride battery. When replacing the battery obey the following:
WARNING:
Replace the nickel metal hydride battery with Genuine CONSULT-II battery only. Use of another bat-
tery may present a risk of fire or explosion. The battery may present a fire or chemical burn hazard if
mistreated. Do not recharge, disassemble of dispose of in fire.
Keep the battery out of reach of children and discard used battery conforming to the local regulations.
Checking EquipmentNBGI0006S07When ordering the below equipment, contact your NISSAN/INFINITI distributor.
Tool name Description
NISSAN CONSULT-II
q
1CONSULT-II unit (Tester internal soft:
Resident version 3.2.0) and accessories
q
2Program card AED99C (Version 3.0)
and UEN99A (For IVIS and IVCS)
To confirm the best combination of these
softwares, refer to CONSULT-II Operation
Manual.
SGI100A
NOTE:
IThe CONSULT-II must be used in conjunction with a program card.
CONSULT-II does not require loading (Initialization) procedure.
IBe sure the CONSULT-II is turned off before installing or removing a program card.
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CONSULT-II CHECKING SYSTEM
Function and System Application (Cont'd)
GI-39

NBGI0010
SAE J1930 Terminology ListNBGI0010S01All emission related terms used in this publication in accordance with SAE J1930 are listed. Accordingly, new
terms, new acronyms/abbreviations and old terms are listed in the following chart.
NEW TERMNEW ACRONYM /
ABBREVIATIONOLD TERM
Air cleaner ACL Air cleaner
Barometric pressure BARO ***
Barometric pressure sensor-BCDD BAROS-BCDD BCDD
Camshaft position CMP ***
Camshaft position sensor CMPS Crank angle sensor
Canister *** Canister
Carburetor CARB Carburetor
Charge air cooler CAC Intercooler
Closed loop CL Closed loop
Closed throttle position switch CTP switch Idle switch
Clutch pedal position switch CPP switch Clutch switch
Continuous fuel injection system CFI system ***
Continuous trap oxidizer system CTOX system ***
Crankshaft position CKP ***
Crankshaft position sensor CKPS ***
Data link connector DLC ***
Diagnostic test mode DTM Diagnostic mode
Diagnostic test mode selector DTM selector Diagnostic mode selector
Diagnostic test mode I DTM I Mode I
Diagnostic test mode II DTM II Mode II
Diagnostic trouble code DTC Malfunction code
Direct fuel injection system DFI system ***
Distributor ignition system DI system Ignition timing control
Early fuel evaporation-mixture heater EFE-mixture heater Mixture heater
Early fuel evaporation system EFE system Mixture heater control
Electrically erasable programmable read
only memoryEEPROM ***
Electronic ignition system EI system Ignition timing control
Engine control EC ***
Engine control module ECM ECCS control unit
Engine coolant temperature ECT Engine temperature
Engine coolant temperature sensor ECTS Engine temperature sensor
Engine modification EM ***
Engine speed RPM Engine speed
Erasable programmable read only
memoryEPROM ***MA
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SAE J1930 TERMINOLOGY LIST
SAE J1930 Terminology List
GI-51

NEW TERMNEW ACRONYM /
ABBREVIATIONOLD TERM
Evaporative emission canister EVAP canister Canister
Evaporative emission system EVAP system Canister control solenoid valve
Exhaust gas recirculation valve EGR valve EGR valve
Exhaust gas recirculation control-BPT
valveEGRC-BPT valve BPT valve
Exhaust gas recirculation control-solenoid
valveEGRC-solenoid valve EGR control solenoid valve
Exhaust gas recirculation temperature
sensorEGRT sensor Exhaust gas temperature sensor
EGR temperature sensor
Flash electrically erasable programmable
read only memoryFEEPROM ***
Flash erasable programmable read only
memoryFEPROM ***
Flexible fuel sensor FFS ***
Flexible fuel system FF system ***
Fuel pressure regulator *** Pressure regulator
Fuel pressure regulator control solenoid
valve*** PRVR control solenoid valve
Fuel tank temperature sensor FTT sensor Tank fuel temperature sensor
Fuel trim FT ***
Heated Oxygen sensor HO2S Exhaust gas sensor
Idle air control system IAC system Idle speed control
Idle air control valve-air regulator IACV-air regulator Air regulator
Idle air control valve-auxiliary air control
valveIACV-AAC valve Auxiliary air control (AAC) valve
Idle air control valve-FICD solenoid valve IACV-FICD solenoid valve FICD solenoid valve
Idle air control valve-idle up control sole-
noid valveIACV-idle up control solenoid valve Idle up control solenoid valve
Idle speed control-FI pot ISC-FI pot FI pot
Idle speed control system ISC system ***
Ignition control IC ***
Ignition control module ICM ***
Indirect fuel injection system IFI system ***
Intake air IA Air
Intake air temperature sensor IAT sensor Air temperature sensor
Knock *** Detonation
Knock sensor KS Detonation sensor
Malfunction indicator lamp MIL Check engine light
Manifold absolute pressure MAP ***
Manifold absolute pressure sensor MAPS ***
SAE J1930 TERMINOLOGY LIST
SAE J1930 Terminology List (Cont'd)
GI-52