2009 INFINITI QX56 engine

DLN-244
< ON-VEHICLE MAINTENANCE >[REAR FINAL DRIVE: R230]
DIFFERENTIAL GEAR OIL
ON-VEHICLE MAINTENANCE
DIFFERENTIAL GEAR OIL
Changing Differential Gear OilINFOID:0000000004193554
DRAINING
1. Stop the engine.
2. Remove the drain plug and gasket from the rear final drive
assembly to drain the differential gear oil.
3. Install the drain plug with a new gasket to the rear final drive assembly. Tighten to the specified torque. Refer to DLN-253,
"Disassembly and Assembly".
CAUTION:
Do not reuse gasket.
FILLING
1. Remove the filler plug and gasket from the rear final drive assembly.
2. Fill the rear final drive assembly with new differential gear oil until the level reaches the specified level near the filler plug hole.
3. Install the filler plug with a new gasket on it to the rear final drive assembly. Tighten to the specified torque. Refer to DLN-253,
"Disassembly and Assembly".
CAUTION:
Do not reuse gasket.
Checking Differential Gear OilINFOID:0000000004193555
OIL LEAKAGE AND OIL LEVEL
1. Make sure that differential gear oil is not leaki ng from the rear final drive assembly or around it.
2. Check the differential gear oil level from the filler plug hole as shown.
CAUTION:
Do not start engine while checki ng differential gear oil level.
3. Install the filler plug with a new gasket on it to the rear final drive assembly. Tighten to the specified torque. Refer to DLN-253,
"Disassembly and Assembly".
CAUTION:
Do not reuse gasket.
LLIA0068E
Differential gear oil
grade and capacity : Refer to
MA-12, "Fluids and
Lubricants".
LLIA0068E
LLIA0068E
Revision: December 20092009 QX56

EC-1
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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-5
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On Board Diagnosis Logic ..................................
..
295
P1211 TCS CONTROL UNIT ...........................296
Description .......................................................... ..296
On Board Diagnosis Logic ....................................296
DTC Confirmation Procedure ................................296
Diagnosis Procedure .............................................296
P1212 TCS COMMUNICATION LINE ..............297
Description .......................................................... ..297
On Board Diagnosis Logic ....................................297
DTC Confirmation Procedure ................................297
Diagnosis Procedure .............................................297
P1217 ENGINE OVER TEMPERATURE .........298
On Board Diagnosis Logic .................................. ..298
Overall Function Check .........................................298
Diagnosis Procedure .............................................299
Main 13 Causes of Overheating ............................300
P1225 TP SENSOR ..........................................302
Component Description ....................................... ..302
On Board Diagnosis Logic ....................................302
DTC Confirmation Procedure ................................302
Diagnosis Procedure .............................................302
P1226 TP SENSOR ..........................................304
Component Description ....................................... ..304
On Board Diagnosis Logic ....................................304
DTC Confirmation Procedure ................................304
Diagnosis Procedure .............................................304
P1421 COLD START CONTROL .....................306
Description .......................................................... ..306
On Board Diagnosis Logic ....................................306
DTC Confirmation Procedure ................................306
Diagnosis Procedure .............................................306
P1550 BATTERY CURRENT SENSOR ...........308
Component Description ....................................... ..308
On Board Diagnosis Logic ....................................308
DTC Confirmation Procedure ................................308
Diagnosis Procedure .............................................308
Component Inspection ..........................................310
P1551, P1552 BATTERY CURRENT SEN-
SOR ..................................................................
312
Component Description ....................................... ..312
On Board Diagnosis Logic ....................................312
DTC Confirmation Procedure ................................312
Diagnosis Procedure .............................................312
Component Inspection ..........................................314
P1553 BATTERY CURRENT SENSOR ...........316
Component Description ....................................... ..316
On Board Diagnosis Logic ....................................316
DTC Confirmation Procedure ................................316
Diagnosis Procedure .............................................316
Component Inspection ..........................................318
P1554 BATTERY CURRENT SENSOR ...........320
Component Description ....................................... ..320
On Board Diagnosis Logic .....................................320
Overall Function Check .........................................320
Diagnosis Procedure .............................................321
Component Inspection ...........................................322
P1564 ICC STEERING SWITCH .....................324
Component Description .........................................324
On Board Diagnosis Logic .....................................324
DTC Confirmation Procedure ................................324
Diagnosis Procedure .............................................324
Component Inspection ...........................................326
P1564 ASCD STEERING SWITCH .................328
Component Description .........................................328
On Board Diagnosis Logic .....................................328
DTC Confirmation Procedure ................................328
Diagnosis Procedure .............................................328
Component Inspection ...........................................330
P1568 ICC FUNCTION ....................................332
On Board Diagnosis Logic .....................................332
DTC Confirmation Procedure ................................332
Diagnosis Procedure .............................................332
P1572 ICC BRAKE SWITCH ..........................333
Component Description .........................................333
On Board Diagnosis Logic .....................................333
DTC Confirmation Procedure ................................333
Diagnosis Procedure .............................................334
Component Inspection ...........................................337
P1572 ASCD BRAKE SWITCH ......................339
Component Description .........................................339
On Board Diagnosis Logic .....................................339
DTC Confirmation Procedure ................................339
Diagnosis Procedure .............................................340
Component Inspection ...........................................343
P1574 ICC VEHICLE SPEED SENSOR .........344
Component Description .........................................344
On Board Diagnosis Logic .....................................344
DTC Confirmation Procedure ................................344
Diagnosis Procedure .............................................344
P1574 ASCD VEHICLE SPEED SENSOR .....346
Component Description .........................................346
On Board Diagnosis Logic .....................................346
DTC Confirmation Procedure ................................346
Diagnosis Procedure .............................................346
P1805 BRAKE SWITCH .................................348
Description .............................................................348
On Board Diagnosis Logic .....................................348
DTC Confirmation Procedure ................................348
Diagnosis Procedure .............................................348
Component Inspection ...........................................350
P2100, P2103 THROTTLE CONTROL MO-
TOR RELAY ....................................................
351
Component Description .........................................351
Revision: December 20092009 QX56

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
Revision: December 20092009 QX56

EC-7
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SYMPTOM DIAGNOSIS ..... .......................475
ENGINE CONTROL SYSTEM SYMPTOMS .. ..475
Symptom Matrix Chart ........................................ ..475
NORMAL OPERATING CONDITION ...............479
Fuel Cut Control (at No Load and High Engine
Speed) ................................................................. ..
479
PRECAUTION ............................................480
PRECAUTIONS .............................................. ..480
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ..
480
On Board Diagnosis (OBD) System of Engine and
A/T .........................................................................
480
Precaution .............................................................481
PREPARATION .........................................484
PREPARATION .............................................. ..484
Special Service Tool ........................................... ..484
Commercial Service Tool ......................................485
ON-VEHICLE MAINTENANCE ..................487
FUEL PRESSURE .......................................... ..487
Fuel Pressure Check ........................................... ..487
EVAP LEAK CHECK ........................................489
How to Detect Fuel Vapor Leakage .................... ..489
ON-VEHICLE REPAIR ...............................491
EVAP CANISTER ............................................491
Removal and Installation ..................................... ..491
Component Inspection ...........................................491
INTAKE VALVE TIMING CONTROL ..............492
Intake Valve Timing Control Solenoid Valve (LH) ..492
Intake Valve Timing Cont rol Solenoid Valve (RH) ..492
Intake Valve Timing Control Position Sensor (LH) ..493
Intake Valve Timing Control Position Sensor (RH) ..493
Camshaft Position Sensor (PHASE) .....................493
SERVICE DATA AND SPECIFICATIONS
(SDS) ............... ...........................................
495
SERVICE DATA AND SPECIFICATIONS
(SDS) ...............................................................
495
Fuel Pressure ...................................................... ..495
Idle Speed and Ignition Timing ..............................495
Calculated Load Value ..........................................495
Mass Air Flow Sensor ............................................495
Intake Air Temperature Sensor .............................495
Engine Coolant Temperature Sensor ....................495
A/F Sensor 1 Heater ..............................................495
Heated Oxygen sensor 2 Heater ...........................496
Crankshaft Position Sensor (POS) ........................496
Camshaft Position Sensor (PHASE) .....................496
Throttle Control Motor ............................................496
Fuel Injector ...........................................................496
Fuel Pump .............................................................496
Revision: December 20092009 QX56

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
Revision: December 20092009 QX56

EC-12
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about a incident. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the one on the next page in order
to organize all the information for troubleshooting.
Some conditions may cause the MIL to come on steady or blink and
DTC to be detected. Examples:
 Vehicle ran out of fuel, which caused the engine to misfire.
 Fuel filler cap was left off or incorrectly screwed on, allowing fuel to
evaporate into the atmosphere.
Worksheet Sample
SEF907L
MTBL0017
Revision: December 20092009 QX56

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
Revision: December 20092009 QX56