electric INFINITI QX56 2009 Factory Service Manual

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< PRECAUTION >[REAR FINAL DRIVE: R230]
PRECAUTIONS
PRECAUTION
PRECAUTIONS
Precaution for Supplemental Restraint S
ystem (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000005877756
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SR and SB section of this Service Man-
ual.
WARNING:
 To avoid rendering the SRS inopera tive, 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 NISS AN/INFINITI dealer.
 Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintent ional activation of the system. For re moval of Spiral Cable and Air Bag
Module, see the SR section.
 Do not use electrical test equipmen t on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS
WARNING:
 When working near the Airbag Diagnosis Sensor Unit or other Airbag System sensors with the Igni-
tion ON or engine running, DO NOT use air or electri c power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
 When using air or electric power tools or hammers , always switch the Ignition OFF, disconnect the
battery, and wait at least 3 minu tes before performing any service.
Precaution Necessary for Steering W heel Rotation After Battery Disconnect
INFOID:0000000005877757
NOTE:
 This Procedure is applied only to models with Intelli gent Key system and NATS (NISSAN ANTI-THEFT SYS-
TEM).
 Remove and install all control units after disconnecting both battery cables with the ignition knob in the
″LOCK ″ position.
 Always use CONSULT-III to perform self-diagnosis as a part of each function inspection after finishing work.
If DTC is detected, perform trouble diagnosis according to self-diagnostic results.
For models equipped with the Intelligent Key system and NATS, an electrically controlled steering lock mech-
anism is adopted on the key cylinder.
For this reason, if the battery is disconnected or if the battery is discharged, the steering wheel will lock and
steering wheel rotation will become impossible.
If steering wheel rotation is required when battery pow er is interrupted, follow the procedure below before
starting the repair operation.
OPERATION PROCEDURE
1. Connect both battery cables. NOTE:
Supply power using jumper cables if battery is discharged.
2. Use the Intelligent Key or mechanical key to turn the ignition switch to the ″ACC ″ position. At this time, the
steering lock will be released.
3. Disconnect both battery cables. The steering lock will remain released and the steering wheel can be
rotated.
4. Perform the necessary repair operation.
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ENGINE
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CONTENTS
ENGINE CONTROL SYSTEM
VK56DE
BASIC INSPECTION ....... .............................
8
DIAGNOSIS AND REPAIR WORKFLOW ..... .....8
Trouble Diagnosis Introduction ........................... ......8
INSPECTION AND ADJUSTMENT ....................13
Basic Inspection .................................................. ....13
Idle Speed and Ignition Timing Check ....................17
Procedure After Replacing ECM .............................17
VIN Registration ......................................................17
Accelerator Pedal Released Position Learning .......18
Throttle Valve Closed Position Learning .................18
Idle Air Volume Learning .........................................18
FUNCTION DIAGNOSIS ..............................21
ENGINE CONTROL SYSTEM ........................ ....21
System Diagram .................................................. ....21
Engine Control Component Parts Location .............22
MULTIPORT FUEL INJECTION SYSTEM .........28
System Description ............................................. ....28
ELECTRIC IGNITION SYSTEM ..................... ....31
System Description ............................................. ....31
AIR CONDITIONING CUT CONTROL ...............32
Input/Output Signal Chart .................................... ....32
System Description .................................................32
AUTOMATIC SPEED CONTROL DEVICE
(ASCD) ...............................................................
33
System Description ............................................. ....33
Component Description ...........................................34
CAN COMMUNICATION ....................................35
System Description ............................................. ....35
COOLING FAN CONTROL ................................36
Description .......................................................... ....36
EVAPORATIVE EMISSION SYSTEM ...............37
Description ........................................................... ....37
INTAKE VALVE TIMING CONTROL ................40
Description ...............................................................40
ON BOARD DIAGNOSTIC (OBD) SYSTEM ....41
Introduction ..............................................................41
Two Trip Detection Logic .........................................41
Emission-related Diagnostic Information .................42
Malfunction Indicator Lamp (MIL) ............................55
OBD System Operation Chart .................................58
CONSULT-III Function (ENGINE) ...........................63
Generic Scan Tool (GST) Function .........................72
COMPONENT DIAGNOSIS .........................74
TROUBLE DIAGNOSIS - SPECIFICATION
VALUE ...............................................................
74
Description ........................................................... ....74
Testing Condition .....................................................74
Inspection Procedure ...............................................74
Diagnosis Procedure ...............................................75
POWER SUPPLY AND GROUND CIRCUIT ....82
Diagnosis Procedure ...............................................82
Ground Inspection ...................................................85
U1000, U1001 CAN COMM CIRCUIT ...............86
Description ...............................................................86
On Board Diagnosis Logic .......................................86
DTC Confirmation Procedure ..................................86
Diagnosis Procedure ...............................................86
P0011, P0021 IVT CONTROL ...........................87
On Board Diagnosis Logic .......................................87
DTC Confirmation Procedure ..................................87
Diagnosis Procedure ...............................................88
Component Inspection .............................................92
P0031, P0032, P0051, P0052 A/F SENSOR 1
HEATER ............................................................
94
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EC-6
On Board Diagnosis Logic .....................................351
DTC Confirmation Procedure ................................351
Diagnosis Procedure .............................................351
P2101 ELECTRIC THROTTLE CONTROL
FUNCTION .......................................................
354
Description ........................................................... ..354
On Board Diagnosis Logic .....................................354
DTC Confirmation Procedure ................................354
Diagnosis Procedure .............................................354
Component Inspection ...........................................357
P2118 THROTTLE CONTROL MOTOR ..........358
Component Description ....................................... ..358
On Board Diagnosis Logic .....................................358
DTC Confirmation Procedure ................................358
Diagnosis Procedure .............................................358
Component Inspection ...........................................359
P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR .....................................................
360
Component Description ....................................... ..360
On Board Diagnosis Logic .....................................360
DTC Confirmation Procedure ................................360
Diagnosis Procedure .............................................361
P2122, P2123 APP SENSOR ..........................362
Component Description ....................................... ..362
On Board Diagnosis Logic .....................................362
DTC Confirmation Procedure ................................362
Diagnosis Procedure .............................................362
Component Inspection ...........................................364
P2127, P2128 APP SENSOR ..........................365
Component Description ....................................... ..365
On Board Diagnosis Logic .....................................365
DTC Confirmation Procedure ................................365
Diagnosis Procedure .............................................365
Component Inspection ...........................................368
P2135 TP SENSOR .........................................369
Component Description ....................................... ..369
On Board Diagnosis Logic .....................................369
DTC Confirmation Procedure ................................369
Diagnosis Procedure .............................................369
Component Inspection ...........................................372
P2138 APP SENSOR ......................................373
Component Description ....................................... ..373
On Board Diagnosis Logic .....................................373
DTC Confirmation Procedure ................................373
Diagnosis Procedure .............................................374
Component Inspection ...........................................376
P2A00, P2A03 A/F SENSOR 1 .......................377
Component Description ....................................... ..377
On Board Diagnosis Logic .....................................377
DTC Confirmation Procedure ................................377
Diagnosis Procedure .............................................378
ASCD BRAKE SWITCH ................................. .383
Component Description ....................................... .383
Diagnosis Procedure .............................................383
Component Inspection ..........................................386
ASCD INDICATOR ...........................................387
Component Description ....................................... .387
Diagnosis Procedure .............................................387
COOLING FAN .................................................388
Diagnosis Procedure ............................................ .388
Component Inspection ..........................................388
ELECTRICAL LOAD SIGNAL ..........................390
Description ........................................................... .390
Diagnosis Procedure .............................................390
FUEL INJECTOR ..............................................392
Component Description ....................................... .392
Diagnosis Procedure .............................................392
Component Inspection ..........................................394
FUEL PUMP .....................................................395
Description ........................................................... .395
Diagnosis Procedure .............................................395
Component Inspection ..........................................398
ICC BRAKE SWITCH ..................................... ..399
Component Description ....................................... .399
Diagnosis Procedure .............................................399
Component Inspection ..........................................402
IGNITION SIGNAL ............................................404
Component Description ....................................... .404
Diagnosis Procedure .............................................404
Component Inspection ..........................................407
ON BOARD REFUELING VAPOR RECOV-
ERY (ORVR) .....................................................
409
System Description .............................................. .409
Diagnosis Procedure .............................................409
Component Inspection ..........................................411
POSITIVE CRANKCASE VENTILATION .........414
Description ........................................................... .414
Component Inspection ..........................................414
REFRIGERANT PRESSURE SENSOR ...........416
Component Description ....................................... .416
Diagnosis Procedure .............................................416
ECU DIAGNOSIS ......................................419
ECM ................................................................ ..419
CONSULT-lll Reference Value in Data Monitor
Mode .................................................................... .
419
ECM Harness Connector Terminal Layout ...........422
ECM Terminal and Reference Value ....................422
Wiring Diagram - ENGINE CONTROL SYSTEM - .432
Fail-Safe Chart ......................................................453
DTC Inspection Priority Chart ...............................455
DTC Index .............................................................456
Emission-related Diagnostic Information ..............460
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EC-8
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis IntroductionINFOID:0000000003771293
INTRODUCTION
The engine has an ECM to control major systems such as fuel con-
trol, ignition control, idle air control system, etc. The ECM accepts
input signals from sensors and instantly drives actuators. It is essen-
tial that both input and output signals are proper and stable. At the
same time, it is important that there are no malfunctions such as vac-
uum leaks, fouled spark plugs, or
other malfunctions with the engine.
It is much more difficult to diagnose an incident that occurs intermit-
tently rather than continuously. Most intermittent incidents are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-III (or GST) or a circuit tester connected should
be performed. Follow the Work Flow on "WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a dr iveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Di agnostic Worksheet like the example
on "Worksheet Sample" should be used.
Start your diagnosis by looking fo r conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.
WORK FLOW
MEF036D
SEF233G
SEF234G
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INSPECTION AND ADJUSTMENTEC-13
< BASIC INSPECTION > [VK56DE]
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INSPECTION AND ADJUSTMENT
Basic InspectionINFOID:0000000003771294
1.INSPECTION START
1. Check service records for any recent repairs that ma y indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
- Harness connectors for improper connections
- Wiring harness for improper connections, pinches and cut
- Vacuum hoses for splits, kinks and improper connections
- Hoses and ducts for leaks
- Air cleaner clogging
- Gasket
3. Confirm that electrical or mechanical loads are not applied.
- Headlamp switch is OFF.
- Air conditioner switch is OFF.
- Rear window defogger switch is OFF.
- Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no load.
6. Make sure that no DTC is displayed with CONSULT-III or GST.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2.REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3.
3.CHECK TARGET IDLE SPEED
With CONSULT-III
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
SEF983U
SEF976U
SEF977U
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EC-18
< BASIC INSPECTION >[VK56DE]
INSPECTION AND ADJUSTMENT
With CONSULT-III
1. Check the VIN of the vehicle and note it. Refer to
GI-20, "Model Variation".
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION ” in “WORK SUPPORT” mode.
4. Follow the instruction of CONSULT-III display.
Accelerator Pedal Released Position LearningINFOID:0000000003771298
DESCRIPTION
Accelerator Pedal Released Position Learning is an operati on to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal positi on sensor output signal. It must be performed each time
harness connector of accelerator pedal pos ition sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningINFOID:0000000003771299
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to l earn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal . It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF wait at least 10 seconds. Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningINFOID:0000000003771300
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:
 Each time electric throttle control actuator or ECM is replaced.
 Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
 Battery voltage: More than 12.9V (At idle)
 Engine coolant temperature: 70 - 100 °C (158 - 212 °F)
 Select lever: P or N
 Electric load switch: OFF (Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine is
start the headlamp will not be illuminated.
 Steering wheel: Neutral (Straight-ahead position)
 Vehicle speed: Stopped
 Transmission: Warmed-up
- With CONSULT-III: Drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indi-
cates less than 0.9V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
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EC-22
< FUNCTION DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM
Engine Control Comp onent Parts Location
INFOID:0000000003771302
1. ECM 2. Battery current sensor 3. Power steering pressure sensor
4. Ignition coil (with power transistor)
and spark plug (bank 2) 5. Refrigerant pressure sensor 6. Intake valve timing control position
sensor (bank 2)
7. Intake valve timing control solenoid valve (bank 2) 8. Engine coolant temperature sensor 9. Electric throttle control actuator
10. Intake valve timing control position sensor (bank 1) 11. Intake valve timing control solenoid
valve (bank 1) 12. Cooling fan motor
13. Camshaft position sensor (PHASE) 14. I gnition coil (with power transistor)
and spark plug (bank 1) 15. Mass air flow sensor (with intake air
temperature sensor)
16. A/F sensor 1 (bank 1) 17. EVAP service port 18. Fuel injector (bank 1)
19. Knock sensor (bank 1) 20. EVAP canister purge volume control solenoid valve21. Knock sensor (bank 2)
22. Fuel injector (bank 2) 23. A/F sensor 1 (bank 2) 24. IPDM E/R
BBIA0743E
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EC-24
< FUNCTION DIAGNOSIS >[VK56DE]
ENGINE CONTROL SYSTEM
10. Camshaft position sensor (PHASE) 11
. Electric throttle control actuator
(view with intake air duct removed) 12. Cooling fan motor harness connec-
tor
: Vehicle front
BBIA0739E
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EC-28
< FUNCTION DIAGNOSIS >[VK56DE]
MULTIPORT FUEL INJECTION SYSTEM
MULTIPORT FUEL INJECTION SYSTEM
System DescriptionINFOID:0000000003771303
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system. This is used only for the on board diagnosis.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is
determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). T he amount of fuel injected is a program value in the
ECM memory. The program value is preset by engi ne operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION I NCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compens ated to improve engine performance under various operat-
ing conditions as listed below.
 During warm-up
 When starting the engine
 During acceleration
 Hot-engine operation
 When selector lever is changed from N to D
 High-load, high-speed operation

 During deceleration
 During high engine speed operation
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
controlFuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
TCM Gear position
Knock sensor Engine knocking condition
Battery
Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
ABS actuator and electric unit (control unit) VDC/TCS operation command*
2
Air conditioner switchAir conditioner operation*2
Wheel sensorVehicle speed*2
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ELECTRIC IGNITION SYSTEMEC-31
< FUNCTION DIAGNOSIS > [VK56DE]
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System DescriptionINFOID:0000000003771304
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1 - 8 - 7 - 3 - 6 - 5 - 4 -2
The ignition timing is controlled by the ECM to maintain
the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor signal. Comput-
ing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revi sed by the ECM according to the other data stored in
the ECM.
 At starting
 During warm-up
At idle
 At low battery voltage
 During acceleration
The knock sensor retard system is designed only for emergencies. The basic ignition timing is programmed
within the anti-knocking zone, if recommended fuel is used under dry conditions. The retard system does not
operate under normal driving conditions. If engine knocking occurs, the knock sensor monitors the condition.
The signal is transmitted to the ECM. The ECM retards the ignition timing to eliminate the knocking condition.
Sensor Input signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
2
Piston position
Ignition timing
controlPower transistor
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
TCM Gear position
Battery
Battery voltage*
2
Wheel sensor
Vehicle speed*1
Revision: December 20092009 QX56