diagram INFINITI QX56 2004 Factory Manual PDF

EC-6Revision: August 20072004 QX56 Component Inspection ..........................................503
Removal and Installation ......................................503
DTC P1446 EVAP CANISTER VENT CONTROL
VALVE .....................................................................504
Component Description ........................................504
CONSULT-II Reference Value in Data Monitor Mode
.504
On Board Diagnosis Logic ....................................504
DTC Confirmation Procedure ...............................505
Wiring Diagram .....................................................506
Diagnostic Procedure ...........................................507
Component Inspection ..........................................508
DTC P1564 ICC STEERING SWITCH ....................510
Component Description ........................................510
CONSULT-II Reference Value in Data Monitor Mode
.510
On Board Diagnosis Logic ....................................510
DTC Confirmation Procedure ...............................510
Wiring Diagram .....................................................512
Diagnostic Procedure ...........................................514
Component Inspection ..........................................516
DTC P1564 ASCD STEERING SWITCH ................517
Component Description ........................................517
CONSULT-II Reference Value in Data Monitor Mode
.517
On Board Diagnosis Logic ....................................517
DTC Confirmation Procedure ...............................518
Wiring Diagram .....................................................519
Diagnostic Procedure ...........................................521
Component Inspection ..........................................522
DTC P1568 ICC FUNCTION ...................................524
On Board Diagnosis Logic ....................................524
DTC Confirmation Procedure ...............................524
Diagnostic Procedure ...........................................524
DTC P1572 ICC BRAKE SWITCH ..........................525
Component Description ........................................525
CONSULT-II Reference Value in Data Monitor Mode
.525
On Board Diagnosis Logic ....................................525
DTC Confirmation Procedure ...............................525
Wiring Diagram .....................................................527
Diagnostic Procedure ...........................................528
Component Inspection ..........................................532
DTC P1572 ASCD BRAKE SWITCH ......................534
Component Description ........................................534
CONSULT-II Reference Value in Data Monitor Mode
.534
On Board Diagnosis Logic ....................................534
DTC Confirmation Procedure ...............................535
Wiring Diagram .....................................................536
Diagnostic Procedure ...........................................537
Component Inspection ..........................................541
DTC P1574 ICC VEHICLE SPEED SENSOR .........542
Component Description ........................................542
On Board Diagnosis Logic ....................................542
DTC Confirmation Procedure ...............................542
Diagnostic Procedure ...........................................543
DTC P1574 ASCD VEHICLE SPEED SENSOR .....544
Component Description ........................................544On Board Diagnosis Logic .................................... 544
DTC Confirmation Procedure ................................ 544
Diagnostic Procedure ............................................ 545
DTC P1706 PNP SWITCH ....................................... 546
Component Description ........................................ 546
CONSULT-II Reference Value in Data Monitor Mode
. 546
On Board Diagnosis Logic .................................... 546
DTC Confirmation Procedure ................................ 546
Overall Function Check ......................................... 547
Wiring Diagram ..................................................... 548
Diagnostic Procedure ............................................ 549
DTC P1805 BRAKE SWITCH ................................. 551
Description ............................................................ 551
CONSULT-II Reference Value in Data Monitor Mode
. 551
On Board Diagnosis Logic .................................... 551
DTC Confirmation Procedure ................................ 551
Wiring Diagram ..................................................... 552
Diagnostic Procedure ............................................ 553
Component Inspection .......................................... 555
DTC P2122, P2123 APP SENSOR ......................... 556
Component Description ........................................ 556
CONSULT-II Reference Value in Data Monitor Mode
. 556
On Board Diagnosis Logic .................................... 556
DTC Confirmation Procedure ................................ 557
Wiring Diagram ..................................................... 558
Diagnostic Procedure ............................................ 559
Component Inspection .......................................... 561
Removal and Installation ....................................... 561
DTC P2127, P2128 APP SENSOR ......................... 562
Component Description ........................................ 562
CONSULT-II Reference Value in Data Monitor Mode
. 562
On Board Diagnosis Logic .................................... 562
DTC Confirmation Procedure ................................ 563
Wiring Diagram ..................................................... 564
Diagnostic Procedure ............................................ 565
Component Inspection .......................................... 568
Removal and Installation ....................................... 568
DTC P2135 TP SENSOR ........................................ 569
Component Description ........................................ 569
CONSULT-II Reference Value in Data Monitor Mode
. 569
On Board Diagnosis Logic .................................... 569
DTC Confirmation Procedure ................................ 570
Wiring Diagram ..................................................... 571
Diagnostic Procedure ............................................ 572
Component Inspection .......................................... 575
Removal and Installation ....................................... 575
DTC P2138 APP SENSOR ...................................... 576
Component Description ........................................ 576
CONSULT-II Reference Value in Data Monitor Mode
. 576
On Board Diagnosis Logic .................................... 576
DTC Confirmation Procedure ................................ 577
Wiring Diagram ..................................................... 578
Diagnostic Procedure ............................................ 579

EC-7
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Revision: August 20072004 QX56 Component Inspection ......................................... 582
Removal and Installation ...................................... 582
IGNITION SIGNAL .................................................. 583
Component Description ........................................ 583
Wiring Diagram .................................................... 584
Diagnostic Procedure ........................................... 589
Component Inspection ......................................... 593
Removal and Installation ...................................... 594
INJECTOR CIRCUIT ............................................... 595
Component Description ........................................ 595
CONSULT-II Reference Value in Data Monitor Mode
. 595
Wiring Diagram .................................................... 596
Diagnostic Procedure ........................................... 597
Component Inspection ......................................... 600
Removal and Installation ...................................... 600
FUEL PUMP CIRCUIT ............................................ 601
Description ........................................................... 601
CONSULT-II Reference Value in Data Monitor Mode
. 601
Wiring Diagram .................................................... 602
Diagnostic Procedure ........................................... 603
Component Inspection ......................................... 606
Removal and Installation ...................................... 606
REFRIGERANT PRESSURE SENSOR ................. 607
Component Description ........................................ 607
Wiring Diagram .................................................... 608
Diagnostic Procedure ........................................... 609
Removal and Installation ....................................... 611
ELECTRICAL LOAD SIGNAL ................................ 612
Description ........................................................... 612
CONSULT-II Reference Value in Data Monitor Mode
. 612
Diagnostic Procedure ........................................... 612
ICC BRAKE SWITCH ............................................. 613
Component Description ........................................ 613
CONSULT-II Reference Value in Data Monitor Mode
. 613
Wiring Diagram .................................................... 614
Diagnostic Procedure ........................................... 615
Component Inspection ......................................... 619
ASCD BRAKE SWITCH ......................................... 621
Component Description ........................................ 621CONSULT-II Reference Value in Data Monitor Mode
.621
Wiring Diagram .....................................................622
Diagnostic Procedure ...........................................623
Component Inspection ..........................................627
ASCD INDICATOR ..................................................628
Component Description ........................................628
CONSULT-II Reference Value in Data Monitor Mode
.628
Wiring Diagram .....................................................629
Diagnostic Procedure ...........................................630
MIL AND DATA LINK CONNECTOR ......................631
Wiring Diagram .....................................................631
EVAPORATIVE EMISSION SYSTEM .....................633
Description ............................................................633
Component Inspection ..........................................636
Removal and Installation ......................................637
How to Detect Fuel Vapor Leakage ......................637
ON BOARD REFUELING VAPOR RECOVERY
(ORVR) ....................................................................640
System Description ...............................................640
Diagnostic Procedure ...........................................641
Component Inspection ..........................................643
POSITIVE CRANKCASE VENTILATION ...............645
Description ............................................................645
Component Inspection ..........................................645
AUTOMATIC SPEED CONTROL DEVICE (ASCD) .647
System Description ...............................................647
Component Description ........................................648
SERVICE DATA AND SPECIFICATIONS (SDS) ....649
Fuel Pressure .......................................................649
Idle Speed and Ignition Timing .............................649
Calculated Load Value ..........................................649
Mass Air Flow Sensor ...........................................649
Intake Air Temperature Sensor .............................649
Engine Coolant Temperature Sensor ...................649
A/F Sensor 1 Heater .............................................649
Heated Oxygen sensor 2 Heater ..........................649
Crankshaft Position Sensor (POS) .......................649
Camshaft Position Sensor (PHASE) ....................649
Throttle Control Motor ...........................................649
Injector ..................................................................650
Fuel Pump ............................................................650

PRECAUTIONS
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Revision: August 20072004 QX56

Do not operate fuel pump when there is no fuel in lines.

Tighten fuel hose clamps to the specified torque.

Do not depress accelerator pedal when starting.

Immediately after starting, do not rev up engine unneces-
sarily.

Do not rev up engine just prior to shutdown.

When installing C.B. ham radio or a mobile phone, be sure
to observe the following as it may adversely affect elec-
tronic control systems depending on installation location.
–Keep the antenna as far as possible from the electronic
control units.
–Keep the antenna feeder line more than 20 cm (8 in) away
from the harness of electronic controls.
Do not let them run parallel for a long distance.
–Adjust the antenna and feeder line so that the standing-
wave radio can be kept smaller.
–Be sure to ground the radio to vehicle body.
Wiring Diagrams and Trouble DiagnosisUBS00GZ8
When you read wiring diagrams, refer to the following:

GI-15, "How to Read Wiring Diagrams"

PG-4, "POWER SUPPLY ROUTING CIRCUIT" for power distribution circuit
When you perform trouble diagnosis, refer to the following:

GI-11, "HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES"

GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident"
BBIA0402E
SEF 7 09 Y
SEF 7 08 Y

ENGINE CONTROL SYSTEM
EC-23
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ENGINE CONTROL SYSTEMPFP:23710
System DiagramUBS00GZB
PBIB2051E

EC-24Revision: August 2007
ENGINE CONTROL SYSTEM
2004 QX56
Vacuum Hose DrawingUBS00GZC
Refer to EC-23, "System Diagram" for Vacuum Control System.
PBIB2052E

BASIC SERVICE PROCEDURE
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21. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HARNESS
1. Turn ignition switch OFF and disconnect battery ground cable.
2. Disconnect ECM harness connector.
3. Disconnect A/F sensor 1 harness connector.
4. Check harness continuity between the following terminals. Refer to EC-431, "
Wiring Diagram" .
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 22.
NG >> 1. Repair open circuit or short to ground or short to power in harness or connectors between ECM
and A/F sensor 1.
2. GO TO 4.
22. PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Reconnect ECM harness connector.
2. Perform EC-44, "
Accelerator Pedal Released Position Learning" .
>> GO TO 23.
23. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-44, "
Throttle Valve Closed Position Learning" .
>> GO TO 24.
24. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-44, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes (With CONSULT-II)>>GO TO 25.
Yes (Without CONSULT-II)>>GO TO 26.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
Bank 1 Bank 2
A/F sensor 1 terminal ECM terminal A/F sensor 1 terminal ECM terminal
1161 76
275277
42424
535557
656658
Continuity should exist.

EC-94Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
Circuit DiagramUBS00H02
BBWA1788E

EC-128Revision: August 2007
POWER SUPPLY AND GROUND CIRCUIT
2004 QX56
POWER SUPPLY AND GROUND CIRCUITPFP:24110
Wiring DiagramUBS00H0F
BBWA11 55 E

EC-130Revision: August 2007
POWER SUPPLY AND GROUND CIRCUIT
2004 QX56
4. DETECT MALFUNCTIONING PART
Check the following.

10A fuse

Harness for open or short between ECM and ignition switch
>> Repair harness or connectors.
5. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-133, "
Ground Inspection" .
OK or NG
OK >> GO TO 6.
NG >> Repair or replace ground connections.
6. CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminals 1, 115, 116 and body ground.
Refer to Wiring Diagram.
3. Also check harness for short to power.
OK or NG
OK >> GO TO 8.
NG >> GO TO 7.
7. DETECT MALFUNCTIONING PART
Check the following.

Harness connectors F32, E2

Harness for open or short between ECM and body ground
>> Repair open circuit or short to power in harness or connectors.
BBIA0354E
Continuity should exist.

EC-132Revision: August 2007
POWER SUPPLY AND GROUND CIRCUIT
2004 QX56
11 . CHECK ECM POWER SUPPLY CIRCUIT-V
1. Disconnect ECM harness connector.
2. Disconnect IPDM E/R harness connector E119.
3. Check harness continuity between ECM terminals 119, 120 and IPDM E/R terminal 3.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 14.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
12. CHECK ECM POWER SUPPLY CIRCUIT-VI
1. Disconnect ECM harness connector.
2. Disconnect IPDM E/R harness connector E119.
3. Check harness continuity between ECM terminal 111 and IPDM E/R terminal 7.
Refer to Wiring Diagram.
4. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 13.
NG >> Repair open circuit or short to ground or short to power in harness or connectors.
13. CHECK 20A FUSE
Check 20A fuse (No. 53, located in the IPDM E/R).
OK or NG
OK >> GO TO 17.
NG >> Replace 20A fuse.
14. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body.
Refer to EC-133, "
Ground Inspection" .
OK or NG
OK >> GO TO 15.
NG >> Repair or replace ground connections.Continuity should exist.
Continuity should exist.
BBIA0354E