2007 INFINITI QX56 wiring

EC-5
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P CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
379
On Board Diagnosis Logic ....................................379
DTC Confirmation Procedure ................................379
Wiring Diagram .....................................................381
Diagnosis Procedure .............................................382
Component Inspection ..........................................384
DTC P0448 EVAP CANISTER VENT CON-
TROL VALVE ...................................................
386
Component Description .........................................386
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
386
On Board Diagnosis Logic ....................................386
DTC Confirmation Procedure ................................386
Wiring Diagram .....................................................388
Diagnosis Procedure .............................................389
Component Inspection ..........................................390
DTC P0451 EVAP CONTROL SYSTEM
PRESSURE SENSOR ......................................
392
Component Description .........................................392
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
392
On Board Diagnosis Logic ....................................392
DTC Confirmation Procedure ................................392
Diagnosis Procedure .............................................393
Component Inspection ..........................................394
DTC P0452 EVAP CONTROL SYSTEM
PRESSURE SENSOR ......................................
395
Component Description .........................................395
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
395
On Board Diagnosis Logic ....................................395
DTC Confirmation Procedure ................................395
Wiring Diagram .....................................................397
Diagnosis Procedure .............................................398
Component Inspection ..........................................400
DTC P0453 EVAP CONTROL SYSTEM
PRESSURE SENSOR ......................................
401
Component Description .........................................401
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
401
On Board Diagnosis Logic ....................................401
DTC Confirmation Procedure ................................401
Wiring Diagram .....................................................403
Diagnosis Procedure .............................................404
Component Inspection ..........................................407
DTC P0455 EVAP CONTROL SYSTEM ..........408
On Board Diagnosis Logic ....................................408
DTC Confirmation Procedure ................................408
Diagnosis Procedure .............................................410
DTC P0456 EVAP CONTROL SYSTEM ..........415
On Board Diagnosis Logic ....................................415
DTC Confirmation Procedure ................................416
Overall Function Check .........................................416
Diagnosis Procedure .............................................417
DTC P0460 FUEL LEVEL SENSOR ...............423
Component Description .........................................423
On Board Diagnosis Logic .....................................423
DTC Confirmation Procedure ................................423
Diagnosis Procedure .............................................424
Removal and Installation .......................................424
DTC P0461 FUEL LEVEL SENSOR ...............425
Component Description .........................................425
On Board Diagnosis Logic .....................................425
Overall Function Check .........................................425
Diagnosis Procedure .............................................426
Removal and Installation .......................................426
DTC P0462, P0463 FUEL LEVEL SENSOR
CIRCUIT ..........................................................
427
Component Description .........................................427
On Board Diagnosis Logic .....................................427
DTC Confirmation Procedure ................................427
Diagnosis Procedure .............................................428
Removal and Installation .......................................428
DTC P0500 VSS ..............................................429
Description .............................................................429
On Board Diagnosis Logic .....................................429
DTC Confirmation Procedure ................................429
Overall Function Check .........................................430
Diagnosis Procedure .............................................430
DTC P0506 ISC SYSTEM ...............................431
Description .............................................................431
On Board Diagnosis Logic .....................................431
DTC Confirmation Procedure ................................431
Diagnosis Procedure .............................................431
DTC P0507 ISC SYSTEM ...............................433
Description .............................................................433
On Board Diagnosis Logic .....................................433
DTC Confirmation Procedure ................................433
Diagnosis Procedure .............................................433
DTC P0550 PSP SENSOR ..............................435
Component Description .........................................435
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
435
On Board Diagnosis Logic .....................................435
DTC Confirmation Procedure ................................435
Wiring Diagram ......................................................436
Diagnosis Procedure .............................................437
Component Inspection ...........................................438
Removal and Installation .......................................439
DTC P0603 ECM POWER SUPPLY ...............440
Component Description .........................................440
On Board Diagnosis Logic .....................................440
DTC Confirmation Procedure ................................440
Wiring Diagram ......................................................441
Diagnosis Procedure .............................................442

EC-6
DTC P0605 ECM ..............................................444
Component Description .........................................444
On Board Diagnosis Logic .....................................444
DTC Confirmation Procedure ................................444
Diagnosis Procedure .............................................445
DTC P0643 SENSOR POWER SUPPLY ........447
On Board Diagnosis Logic .....................................447
DTC Confirmation Procedure ................................447
Wiring Diagram ......................................................448
Diagnosis Procedure .............................................449
DTC P0850 PNP SWITCH ...............................452
Component Description .........................................452
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
452
On Board Diagnosis Logic .....................................452
DTC Confirmation Procedure ................................452
Overall Function Check .........................................453
Wiring Diagram ......................................................454
Diagnosis Procedure .............................................455
DTC P1140, P1145 IVT CONTROL POSITION
SENSOR ..........................................................
457
Component Description .........................................457
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
457
On Board Diagnosis Logic .....................................457
DTC Confirmation Procedure ................................457
Wiring Diagram ......................................................458
Diagnosis Procedure .............................................461
Component Inspection ...........................................463
Removal and Installation .......................................464
DTC P1148, P1168 CLOSED LOOP CON-
TROL ................................................................
466
On Board Diagnosis Logic .....................................466
DTC P1211 TCS CONTROL UNIT ..................467
Description .............................................................467
On Board Diagnosis Logic .....................................467
DTC Confirmation Procedure ................................467
Diagnosis Procedure .............................................467
DTC P1212 TCS COMMUNICATION LINE .....468
Description .............................................................468
On Board Diagnosis Logic .....................................468
DTC Confirmation Procedure ................................468
Diagnosis Procedure .............................................468
DTC P1217 ENGINE OVER TEMPERATURE .469
Description .............................................................469
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
469
On Board Diagnosis Logic .....................................470
Overall Function Check .........................................470
Wiring Diagram ......................................................472
Diagnosis Procedure .............................................473
Main 13 Causes of Overheating ............................476
Component Inspection ...........................................476
DTC P1225 TP SENSOR ..................................477
Component Description ........................................477
On Board Diagnosis Logic ....................................477
DTC Confirmation Procedure ................................477
Diagnosis Procedure .............................................477
Removal and Installation .......................................478
DTC P1226 TP SENSOR ..................................479
Component Description ........................................479
On Board Diagnosis Logic ....................................479
DTC Confirmation Procedure ................................479
Diagnosis Procedure .............................................479
Removal and Installation .......................................480
DTC P1421 COLD START CONTROL ............481
Description ............................................................481
On Board Diagnosis Logic ....................................481
DTC Confirmation Procedure ................................481
Diagnosis Procedure .............................................481
DTC P1550 BATTERY CURRENT SENSOR ...483
Component Description ........................................483
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
483
On Board Diagnosis Logic ....................................483
DTC Confirmation Procedure ................................483
Wiring Diagram .....................................................485
Diagnosis Procedure .............................................486
Component Inspection ..........................................488
DTC P1551, P1552 BATTERY CURRENT
SENSOR ...........................................................
489
Component Description ........................................489
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
489
On Board Diagnosis Logic ....................................489
DTC Confirmation Procedure ................................489
Wiring Diagram .....................................................491
Diagnosis Procedure .............................................492
Component Inspection ..........................................494
DTC P1553 BATTERY CURRENT SENSOR ...495
Component Description ........................................495
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
495
On Board Diagnosis Logic ....................................495
DTC Confirmation Procedure ................................495
Wiring Diagram .....................................................497
Diagnosis Procedure .............................................498
Component Inspection ..........................................500
DTC P1554 BATTERY CURRENT SENSOR ...501
Component Description ........................................501
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
501
On Board Diagnosis Logic ....................................501
Overall Function Check .........................................501
Wiring Diagram .....................................................503
Diagnosis Procedure .............................................504
Component Inspection ..........................................506

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DTC P1564 ICC STEERING SWITCH .............507
Component Description .........................................507
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
507
On Board Diagnosis Logic ....................................507
DTC Confirmation Procedure ................................507
Wiring Diagram .....................................................509
Diagnosis Procedure .............................................510
Component Inspection ..........................................512
DTC P1564 ASCD STEERING SWITCH .........513
Component Description .........................................513
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
513
On Board Diagnosis Logic ....................................513
DTC Confirmation Procedure ................................513
Wiring Diagram .....................................................515
Diagnosis Procedure .............................................516
Component Inspection ..........................................518
DTC P1568 ICC FUNCTION ............................519
On Board Diagnosis Logic ....................................519
DTC Confirmation Procedure ................................519
Diagnosis Procedure .............................................519
DTC P1572 ICC BRAKE SWITCH ...................520
Component Description .........................................520
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
520
On Board Diagnosis Logic ....................................520
DTC Confirmation Procedure ................................520
Wiring Diagram .....................................................522
Diagnosis Procedure .............................................523
Component Inspection ..........................................526
DTC P1572 ASCD BRAKE SWITCH ...............528
Component Description .........................................528
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
528
On Board Diagnosis Logic ....................................528
DTC Confirmation Procedure ................................528
Wiring Diagram .....................................................530
Diagnosis Procedure .............................................531
Component Inspection ..........................................534
DTC P1574 ICC VEHICLE SPEED SENSOR ..535
Component Description .........................................535
On Board Diagnosis Logic ....................................535
DTC Confirmation Procedure ................................535
Diagnosis Procedure .............................................536
DTC P1574 ASCD VEHICLE SPEED SEN-
SOR ..................................................................
537
Component Description .........................................537
On Board Diagnosis Logic ....................................537
DTC Confirmation Procedure ................................537
Diagnosis Procedure .............................................538
DTC P1805 BRAKE SWITCH ..........................539
Description ............................................................539
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
539
On Board Diagnosis Logic .....................................539
DTC Confirmation Procedure ................................539
Wiring Diagram ......................................................540
Diagnosis Procedure .............................................541
Component Inspection ...........................................542
DTC P2100, P2103 THROTTLE CONTROL
MOTOR RELAY ..............................................
543
Component Description .........................................543
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
543
On Board Diagnosis Logic .....................................543
DTC Confirmation Procedure ................................543
Wiring Diagram ......................................................545
Diagnosis Procedure .............................................546
DTC P2101 ELECTRIC THROTTLE CON-
TROL FUNCTION ...........................................
548
Description .............................................................548
On Board Diagnosis Logic .....................................548
DTC Confirmation Procedure ................................548
Wiring Diagram ......................................................549
Diagnosis Procedure .............................................550
Component Inspection ...........................................553
Removal and Installation .......................................553
DTC P2118 THROTTLE CONTROL MOTOR .554
Component Description .........................................554
On Board Diagnosis Logic .....................................554
DTC Confirmation Procedure ................................554
Wiring Diagram ......................................................555
Diagnosis Procedure .............................................556
Component Inspection ...........................................557
Removal and Installation .......................................557
DTC P2119 ELECTRIC THROTTLE CON-
TROL ACTUATOR ..........................................
559
Component Description .........................................559
On Board Diagnosis Logic .....................................559
DTC Confirmation Procedure ................................559
Diagnosis Procedure .............................................560
DTC P2122, P2123 APP SENSOR .................561
Component Description .........................................561
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
561
On Board Diagnosis Logic .....................................561
DTC Confirmation Procedure ................................561
Wiring Diagram ......................................................563
Diagnosis Procedure .............................................564
Component Inspection ...........................................566
Removal and Installation .......................................566
DTC P2127, P2128 APP SENSOR .................567
Component Description .........................................567
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
567
On Board Diagnosis Logic .....................................567

EC-8
DTC Confirmation Procedure ................................567
Wiring Diagram ......................................................569
Diagnosis Procedure .............................................570
Component Inspection ...........................................572
Removal and Installation .......................................573
DTC P2135 TP SENSOR .................................574
Component Description .........................................574
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
574
On Board Diagnosis Logic .....................................574
DTC Confirmation Procedure ................................574
Wiring Diagram ......................................................576
Diagnosis Procedure .............................................577
Component Inspection ...........................................579
Removal and Installation .......................................580
DTC P2138 APP SENSOR ..............................581
Component Description .........................................581
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
581
On Board Diagnosis Logic .....................................581
DTC Confirmation Procedure ................................582
Wiring Diagram ......................................................583
Diagnosis Procedure .............................................584
Component Inspection ...........................................587
Removal and Installation .......................................587
DTC P2A00, P2A03 A/F SENSOR 1 ...............588
Component Description .........................................588
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
588
On Board Diagnosis Logic .....................................588
DTC Confirmation Procedure ................................588
Wiring Diagram ......................................................590
Diagnosis Procedure .............................................593
Removal and Installation .......................................596
ASCD BRAKE SWITCH ..................................597
Component Description .........................................597
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
597
Wiring Diagram ......................................................598
Diagnosis Procedure .............................................599
Component Inspection ...........................................602
ASCD INDICATOR ..........................................603
Component Description .........................................603
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
603
Wiring Diagram ......................................................604
Diagnosis Procedure .............................................604
ELECTRICAL LOAD SIGNAL .........................606
Description .............................................................606
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
606
Diagnosis Procedure .............................................606
FUEL INJECTOR ..............................................608
Component Description ........................................608
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
608
Wiring Diagram .....................................................609
Diagnosis Procedure .............................................610
Component Inspection ..........................................612
Removal and Installation .......................................612
FUEL PUMP .....................................................613
Description ............................................................613
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
613
Wiring Diagram .....................................................614
Diagnosis Procedure .............................................615
Component Inspection ..........................................617
Removal and Installation .......................................618
ICC BRAKE SWITCH .......................................619
Component Description ........................................619
CONSULT-II Reference Value in Data Monitor
Mode .....................................................................
619
Wiring Diagram .....................................................620
Diagnosis Procedure .............................................621
Component Inspection ..........................................624
IGNITION SIGNAL ............................................626
Component Description ........................................626
Wiring Diagram .....................................................627
Diagnosis Procedure .............................................632
Component Inspection ..........................................635
Removal and Installation .......................................637
REFRIGERANT PRESSURE SENSOR ...........638
Component Description ........................................638
Wiring Diagram .....................................................639
Diagnosis Procedure .............................................640
Removal and Installation .......................................642
MIL AND DATA LINK CONNECTOR ...............643
Wiring Diagram .....................................................643
SERVICE DATA AND SPECIFICATIONS
(SDS) ................................................................
645
Fuel Pressure ........................................................645
Idle Speed and Ignition Timing .............................645
Calculated Load Value ..........................................645
Mass Air Flow Sensor ...........................................645
Intake Air Temperature Sensor .............................645
Engine Coolant Temperature Sensor ...................645
A/F Sensor 1 Heater .............................................645
Heated Oxygen sensor 2 Heater ..........................645
Crankshaft Position Sensor (POS) .......................646
Camshaft Position Sensor (PHASE) .....................646
Throttle Control Motor ...........................................646
Fuel Injector ..........................................................646
Fuel Pump .............................................................646

PRECAUTIONS
EC-17
< SERVICE INFORMATION >
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PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER"
INFOID:0000000003531580
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity 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 whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WARNING:
• To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including incorrect removal and installation of the SRS, can lead to personal
injury caused by unintentional activation of the system. For removal of Spiral Cable and Air Bag
Module, see the SRS section.
• Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or har-
ness connectors.
On Board Diagnosis (OBD) System of Engine and A/TINFOID:0000000003531581
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch OFF and disconnect the negative battery cable before any repair
or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc. will
cause the MIL to light up.
• Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For description and how to disconnect, refer to PG-66
.
• Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to light up due to the short circuit.
• Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the EVAP system or fuel injection system,
etc.
• Be sure to erase the unnecessary malfunction information (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
PrecautionINFOID:0000000003531582
•Always use a 12 volt battery as power source.
•Do not attempt to disconnect battery cables while engine is
running.
•Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
•Before removing parts, turn ignition switch OFF and then dis-
connect negative battery cable.
SEF289H

EC-32
< SERVICE INFORMATION >
CAN COMMUNICATION
CAN COMMUNICATION
System DescriptionINFOID:0000000003531593
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
Refer to LAN-44, "
CAN System Specification Chart", about CAN communication for detail.

BASIC SERVICE PROCEDURE
EC-71
< SERVICE INFORMATION >
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BASIC SERVICE PROCEDURE
Basic InspectionINFOID:0000000003531609
1.INSPECTION START
1. Check service records for any recent repairs that may 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-II 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-II
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
SEF983U
SEF976U
SEF977U

EC-82
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
TROUBLE DIAGNOSIS
Trouble Diagnosis IntroductionINFOID:0000000003531617
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-II (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 driveability 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 Diagnostic Worksheet like the example
on "Worksheet Sample" should be used.
Start your diagnosis by looking for conventional malfunctions first.
This will help troubleshoot driveability malfunctions on an electroni-
cally controlled engine vehicle.
WORK FLOW
MEF036D
SEF233G
SEF234G