2005 INFINITI QX4 check engine

SERVICE INFORMATION FOR ELECTRICAL INCIDENT
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How to Perform Efficient Diagnosis for an Electrical IncidentEAS001FN
WORK FLOW
INCIDENT SIMULATION TESTS
Introduction
Sometimes the symptom is not present when the vehicle is brought in for service. If possible, re-create the
conditions present at the time of the incident. Doing so may help avoid a No Trouble Found Diagnosis. The fol-
lowing section illustrates ways to simulate the conditions/environment under which the owner experiences an
electrical incident.
The section is broken into the six following topics:

Vehicle vibration

Heat sensitive
SG I8 38
STEP DESCRIPTION
STEP 1Get detailed information about the conditions and the environment when the incident occurred.
The following are key pieces of information required to make a good analysis:
WHATVehicle Model, Engine, Transmission/Transaxle and the System (i.e. Radio).
WHENDate, Time of Day, Weather Conditions, Frequency.
WHERERoad Conditions, Altitude and Traffic Situation.
HOWSystem Symptoms, Operating Conditions (Other Components Interaction).
Service History and if any After Market Accessories have been installed.
STEP 2Operate the system, road test if necessary.
Verify the parameter of the incident.
If the problem cannot be duplicated, refer to “Incident Simulation Tests”.
STEP 3Get the proper diagnosis materials together including:

Power Supply Routing

System Operation Descriptions

Applicable Service Manual Sections

Check for any Service Bulletins
Identify where to begin diagnosis based upon your knowledge of the system operation and the customer comments.
STEP 4Inspect the system for mechanical binding, loose connectors or wiring damage.
Determine which circuits and components are involved and diagnose using the Power Supply Routing and Harness
Layouts.
STEP 5 Repair or replace the incident circuit or component.
STEP 6Operate the system in all modes. Verify the system works properly under all conditions. Make sure you have not inad-
vertently created a new incident during your diagnosis or repair steps.

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SERVICE INFORMATION FOR ELECTRICAL INCIDENT
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Freezing

Water intrusion

Electrical load

Cold or hot start up
Get a thorough description of the incident from the customer. It is important for simulating the conditions of the
problem.
Vehicle Vibration
The problem may occur or become worse while driving on a rough road or when engine is vibrating (idle with
A/C on). In such a case, you will want to check for a vibration related condition. Refer to the following illustra-
tion.
CONNECTORS & HARNESS
Determine which connectors and wiring harness would affect the electrical system you are inspecting. Gently
shake each connector and harness while monitoring the system for the incident you are trying to duplicate.
This test may indicate a loose or poor electrical connection.
HINT
Connectors can be exposed to moisture. It is possible to get a thin film of corrosion on the connector termi-
nals. A visual inspection may not reveal this without disconnecting the connector. If the problem occurs inter-
mittently, perhaps the problem is caused by corrosion. It is a good idea to disconnect, inspect and clean the
terminals on related connectors in the system.
SENSORS & RELAYS
Gently apply a slight vibration to sensors and relays in the system you are inspecting.
This test may indicate a loose or poorly mounted sensor or relay.
ENGINE COMPARTMENT
There are several reasons a vehicle or engine vibration could cause an electrical complaint. Some of the
things to check for are:

Connectors not fully seated.

Wiring harness not long enough and is being stressed due to engine vibrations or rocking.

Wires laying across brackets or moving components.

Loose, dirty or corroded ground wires.

Wires routed too close to hot components.
To inspect components under the hood, start by verifying the integrity of ground connections. (Refer to Ground
Inspection described later.) First check that the system is properly grounded. Then check for loose connection
by gently shaking the wiring or components as previously explained. Using the wiring diagrams inspect the
wiring for continuity.
BEHIND THE INSTRUMENT PANEL
An improperly routed or improperly clamped harness can become pinched during accessory installation. Vehi-
cle vibration can aggravate a harness which is routed along a bracket or near a screw.
UNDER SEATING AREAS
SG I8 39

CONSULT-II CHECKING SYSTEM
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CONSULT-II CHECKING SYSTEMPFP:00000
DescriptionEAS001XR

CONSULT-II is a hand-held type tester. When it is connected with a diagnostic connector equipped on the
vehicle side, it will communicate with the control unit equipped in the vehicle and then enable various
kinds of diagnostic tests.

Refer to “CONSULT Operator's Manual” for more information.
Function and System ApplicationEAS001XS
x: Applicable.
*1: IVIS (NATS) [Infiniti Vehicle Immobilizer System (Nissan Anti-Theft System)].
*2: This system is shown with IVIS (NATS) using program card AEN04A-1 or later.Diagnostic test
modeFunction
ENGINE
A/T
ICC
ABS
AIR BAG
IPDM E/R
BCM
AUTO DRIVE POS.
REARVIEW CAMERA
AIR LEVELIZER
ALL MODE AWD/4WD
HVAC
NVIS (NATS)
*1
NVIS (NATS BCM OR S/ENT)
*1
Work supportThis mode enables a technician to adjust some devices
faster and more accurately by following the indications on
CONSULT-II.x - xx - - xxxxx - - -
Self-diagnosticSelf-diagnostic can be performed quickly. ----x---------
Self-diagnos-
tic resultsSelf-diagnostic results can be read and erased quickly. xxxx - xxx - xxxxx
Trouble diag-
nostic recordCurrent self-diagnostic results and all trouble diagnostic
records previously stored can be read.--- - x---------
Data monitor Input/Output data in the ECM can be read. xxxx - x - xxxxx - -
Data monitor
(spec)Data monitor specification can be read. x-------------
CAN diagno-
sis support
monitorThe communication condition of CAN communication line
can be read.xxxx - xxx - - xx - -
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-xx-x-x-x----
Function testThis mode can show results of self-diagnosis of ECU with
either “OK” or “NG”. For engines, more practical tests
regarding sensors/switches and/or actuators are avail-
able.xx-xx- --- -----
DTC & SRT
confirmationThe results of SRT (System Readiness Test) and the self-
diagnosis status/result can be confirmed.x-------------
DTC work sup-
portThe operating condition to confirm Diagnosis Trouble
Codes can be selected.xx------------
ECM/ECU part
numberECM/ECU part number can be read. x x x x - - x x x x x x - -
ECU discrimi-
nated No.Classification number of a replacement ECU can be read
to prevent an incorrect ECU from being installed.----x---------
Configuration Sets control module parameters to match vehicle options.------x-------
PIN read
*2This mode shows the BCM-specific 5-digit code. -------------x
Control unit
initialization
*2All registered ignition key IDs in NATS components can
be initialized and new IDs can be registered.------------x-

CONSULT-II CHECKING SYSTEM
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2. If necessary, turn on the ignition switch.
3. Touch “START (NISSAN BASED VHCL)” or system shortcut (eg:
ENGINE) on the screen.
CONSULT-II Data Link Connector (DLC) CircuitEAS001XW
INSPECTION PROCEDURE
If the CONSULT-II cannot diagnose the system properly, check the following items:
NOTE:
The preceding schematic is an example and may not be a true representation of the vehicle. The actual DDL1
circuits (CAN lines) from DLC pins 6 and 14 as well as the DDL2 circuit (K-line) from DLC pin 7 may be con-
nected to more than one system. A short in a DDL circuit connected to a control unit in one system may affect
CONSULT-II access to other systems.
BCIA0029E
LAIA0028E
Symptom Check item
CONSULT-II cannot access
any system.

CONSULT-II DLC power supply circuit (Terminal 8) and ground circuit (Terminal 4). For detailed cir-
cuit, refer to EC-667, "
Wiring Diagram" .

CONSULT-II DLC cable and CONSULT-II CONVERTER.
CONSULT-II cannot access
individual system. (Other sys-
tems can be accessed.)

CONSULT-II program card (Check the appropriate CONSULT-II program card for the system.
Refer to GI-38, "
Checking Equipment" .

Power supply and ground circuit for the control unit of the system (For detailed circuit, refer to wir-
ing diagram for each system.)

Open or short circuit between the system and CONSULT-II DLC (For detailed circuit, refer to wiring
diagram for each system.)

Open or short circuit in CAN or K communication line. Refer to LAN-3, "Precautions When Using
CONSULT-II" .

IDENTIFICATION INFORMATION
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Identification NumberEAS001G3
VEHICLE IDENTIFICATION NUMBER ARRANGEMENT
1. Emission control information label 2. Tire placard 3. F.M.V.S.S. certification label
4. Vehicle identification number plate 5. Vacuum hose diagram
WAIA0053E
Position Character Qualifier Definition
1
5N3 Manufacturer 5N3: USA produced multi-purpose vehicle 2
3
4 A Engine type A: VK56DE
5 A Vehicle line A: Infiniti QX56
6 0 Model change (0-9)
7 8 Body type 8: 4 door wagon
8AGross vehicle
weight ratingA: 2WD, 4-wheel ABS, Class E
B: 4WD, 4-wheel ABS, Class E
9 * Check digit(0 to 9 or X) The code for the check digit is determined by a mathematical
computation.
10 5 Model year 2005
11 NManufacturing
plantN: Canton Mississippi
12
XXXXXVehicle serial num-
berChassis number 13
14
15
16
17

TERMINOLOGY
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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 sen-
sor
EGRT 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 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 ***
Manifold differential pressure MDP ***
Manifold differential pressure sensor MDPS ***
Manifold surface temperature MST ***
Manifold surface temperature sensor MSTS ***
Manifold vacuum zone MVZ ***
Manifold vacuum zone sensor MVZS ***
Mass air flow sensor MAFS Air flow meter
Mixture control solenoid valve MC solenoid valve Air-fuel ratio control solenoid valve
Multiport fuel injection System MFI system Fuel injection controlNEW TERMNEW ACRONYM /
ABBREVIATIONOLD TERM

GW-6
SQUEAK AND RATTLE TROUBLE DIAGNOSES
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DUPLICATE THE NOISE AND TEST DRIVE
If possible, drive the vehicle with the customer until the noise is duplicated. Note any additional information on
the Diagnostic Worksheet regarding the conditions or location of the noise. This information can be used to
duplicate the same conditions when you confirm the repair.
If the noise can be duplicated easily during the test drive, to help identify the source of the noise, try to dupli-
cate the noise with the vehicle stopped by doing one or all of the following:
1) Close a door.
2) Tap or push/pull around the area where the noise appears to be coming from.
3) Rev the engine.
4) Use a floor jack to recreate vehicle “twist”.
5) At idle, apply engine load (electrical load, half-clutch on M/T model, drive position on A/T model).
6) Raise the vehicle on a hoist and hit a tire with a rubber hammer.

Drive the vehicle and attempt to duplicate the conditions the customer states exist when the noise occurs.

If it is difficult to duplicate the noise, drive the vehicle slowly on an undulating or rough road to stress the
vehicle body.
CHECK RELATED SERVICE BULLETINS
After verifying the customer concern or symptom, check ASIST for Technical Service Bulletins (TSBs) related
to that concern or symptom.
If a TSB relates to the symptom, follow the procedure to repair the noise.
LOCATE THE NOISE AND IDENTIFY THE ROOT CAUSE
1. Narrow down the noise to a general area.To help pinpoint the source of the noise, use a listening tool
(Chassis Ear: J-39570, Engine Ear: J-39565 and mechanic's stethoscope).
2. Narrow down the noise to a more specific area and identify the cause of the noise by:

removing the components in the area that you suspect the noise is coming from.
Do not use too much force when removing clips and fasteners, otherwise clips and fasteners can be bro-
ken or lost during the repair, resulting in the creation of new noise.

tapping or pushing/pulling the component that you suspect is causing the noise.
Do not tap or push/pull the component with excessive force, otherwise the noise will be eliminated only
temporarily.

feeling for a vibration with your hand by touching the component(s) that you suspect is (are) causing the
noise.

placing a piece of paper between components that you suspect are causing the noise.

looking for loose components and contact marks.
Refer to GW-7, "
Generic Squeak and Rattle Troubleshooting" .
REPAIR THE CAUSE

If the cause is a loose component, tighten the component securely.

If the cause is insufficient clearance between components:
–separate components by repositioning or loosening and retightening the component, if possible.
–insulate components with a suitable insulator such as urethane pads, foam blocks, felt cloth tape or ure-
thane tape. A NISSAN Squeak and Rattle Kit (J-43980) is available through your authorized NISSAN
Parts Department.
CAUTION:
Do not use excessive force as many components are constructed of plastic and may be damaged.
Always check with the Parts Department for the latest parts information.
The following materials are contained in the NISSAN Squeak and Rattle Kit (J-43980). Each item can be
ordered separately as needed.
URETHANE PADS [1.5 mm (0.059 in) thick]
Insulates connectors, harness, etc.
76268-9E005: 100×135 mm (3.94×5.31 in)/76884-71L01: 60×85 mm (2.36×3.35 in)/76884-71L02: 15×25
mm (0.59×0.98 in)
INSULATOR (Foam blocks)
Insulates components from contact. Can be used to fill space behind a panel.
73982-9E000: 45 mm (1.77 in) thick, 50×50 mm (1.97×1.97 in)/73982-50Y00: 10 mm (0.39 in) thick,
50×50 mm (1.97×1.97 in)
INSULATOR (Light foam block)

IDX-4
ALPHABETICAL INDEX
Drive chain (Transfer) ......................... TF-147, TF-174
Drive pinion diff. inspection ............................. RFD-13
Drive pinion height .......................................... RFD-18
Drive shaft (rear) ............................................... RAX-7
Driver air bag .................................................. SRS-46
DTC work support ............................................ EC-136
DTRL - Wiring diagram ....................................... LT-37
Duct and grilles .............................................. ATC-170
DVD Player ........................................................ AV-60
E
ECM input/output signal ..................... EC-117
, EC-141
ECM power supply ............................. EC-157, EC-393
ECM relay ........................................................ EC-157
ECM/PW - Wiring diagram ............................... EC-394
ECTS - Wiring diagram .................................... EC-197
Electric sunroof .................................................. RF-10
Electric throttle control actuator ......... EC-397, EC-399
Electrical load signal circuit .............................. EC-648
Electrical units location ...................................... PG-63
Electronic ignition (EI) system ........................... EC-26
Engine control circuit diagram ......................... EC-115
Engine control component parts location ......... EC-108
Engine control module (ECM) .......................... EC-383
Engine control system diagram ......................... EC-23
Engine coolant .................................................. CO-10
Engine coolant temperature sensor (ECTS) ... EC-195,
EC-208
Engine fail-safe system .................................... EC-103
Engine oil ............................................................. LU-7
Engine oil filter replacement ............................. MA-17
Engine oil precautions .......................................... GI-7
Engine oil replacement ..................................... MA-17
Engine removal ................................................. EM-69
Engine room cover ............................................ EM-11
Engine serial number .......................................... GI-48
ETC1 - Wiring diagram .................................... EC-400
ETC2 - Wiring diagram .................................... EC-407
ETC3 - Wiring diagram .................................... EC-411
EVAP canister .................................................... EC-35
EVAP canister purge volume control solenoid valve ....
EC-318
, EC-531
EVAP canister vent control valve ....... EC-325, EC-539
EVAP control system (small leak) diagnosis .. EC-309,
EC-349
, EC-357
EVAP control system pressure sensor .... EC-332, EC-
335, EC-341
EVAP control system purge flow monitoring diagnosis
EC-304
EVAP vapor lines inspection ............................. MA-20
Evaporative emission (EVAP) system ............... EC-32
Evaporator ..................................................... ATC-186
Exhaust manifold .............................................. EM-19
Exhaust system ................................................... EX-3
Exhaust system inspection .................................. EX-3
Expansion valve ............................................. ATC-188
F
F/FOG - Wiring diagram ..................................... LT-71
F/PUMP - Wiring diagram ............................... EC-638
Final drive pre-inspection .................. FFD-14, RFD-13
Final drive removal and installation ... FFD-11, RFD-10
Flow charts .......................................................... GI-27
Fluid temperature sensor (A/T) ........................ AT-126
Fluids ................................................................ MA-11
Fluorescent leak detector .............................. ATC-189
Fog lamp, front ................................................... LT-69
Foot lamp ......................................................... LT-130
Freeze frame data ............................... EC-54, EC-130
Front brake solenoid valve ................. AT-144, AT-146
Front bumper ...................................................... EI-13
Front case (Transfer) .......................... TF-147, TF-174
Front combination lamp removal and installation LT-32
Front door ............................. BL-128, BL-131, GW-68
Front Door Trim ................................................... EI-32
Front drive shaft (Transfer) ................. TF-147, TF-174
Front fog lamp .................................................... LT-69
Front passenger air bag .................................. SRS-51
Front seat ........................................................... SE-97
Front seat belt ...................................................... SB-3
Front seat belt pre-tensioner ............... SRS-3, SRS-58
Front washer ...................................................... WW-4
Front wiper ......................................................... WW-4
FTTS - Wiring diagram ...................... EC-255, EC-260
Fuel cut control (at no load high engine speed) EC-27
Fuel filter replacement ......................................... FL-5
Fuel gauge ............................................................ DI-5
Fuel injection system (Bank 1) .......... EC-236, EC-245
Fuel injection system (Bank 2) .......... EC-236, EC-245
Fuel injector and fuel tube ................................. EM-29
Fuel level sensor ................. EC-366, EC-368, EC-370
Fuel line inspection .............................................. FL-3
Fuel pressure check .......................................... EC-93
Fuel pressure release ....................................... EC-93
Fuel pump ....................................................... EC-637
Fuel pump and gauge .......................................... FL-5
Fuel system .......................................................... FL-3
Fuel tank .............................................................. FL-9
Fuel tank temperature sensor ........... EC-253, EC-259
Fuel tank vacuum relief valve ........................... EC-35
FUELB1 - Wiring diagram ................. EC-238, EC-247
FUELB2 - Wiring diagram ................. EC-239, EC-248
Fuse ...................................................... PG-66, PG-77
Fuse and fusible link box .................................. PG-77
Fuse block ......................................................... PG-76
Fusible link ............................................ PG-66, PG-77
G
Garage jack and safety stand ............................. GI-40
Gauges ................................................................. DI-5
Generator .......................................................... SC-17
Generic scan tool (GST) ................................. EC-139
Glass ...................................... GW-11, GW-68, GW-71
Glove box lamp ................................................ LT-153