2004 INFINITI QX56 service indicator

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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

EC-16Revision: August 2007
PRECAUTIONS
2004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
UBS00GZ5
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.
WAR NIN G:

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 per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal 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
harness connectors.
On Board Diagnostic (OBD) System of Engine and A/TUBS00GZ6
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-
locking type harness connector. For description and how to disconnect, refer to PG-68, "
HAR-
NESS CONNECTOR" .

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.
PrecautionUBS00GZ7

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
battery 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
disconnect battery ground cable.
SEF 2 89 H

BASIC SERVICE PROCEDURE
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Revision: August 20072004 QX56
INSPECTION PROCEDURE
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.
SEF 9 83 U
SEF 9 76 U
SEF 9 77 U

EC-42Revision: August 2007
BASIC SERVICE PROCEDURE
2004 QX56
25. CHECK CO%
With CONSULT-II
1. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
2. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
3. Select “ENG COOLANT TEMP” in “ACTIVE TEST” mode.
4. Set “ENG COOLANT TEMP” to 5°C (41°F) by touching “DWN”
and “Qd”.
5. Start engine and rev it (2,000 to 3,000 rpm) two or three times
under no load, then run engine at idle speed.
6. Check CO%.
OK or NG
OK >> GO TO 28.
NG >> GO TO 27.
26. CHECK CO%
Without CONSULT-II
1. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
2. Turn ignition switch OFF.
3. Disconnect engine coolant temperature sensor harness connector.
4. Connect a resistor (4.4 kΩ) between terminals of engine coolant
temperature sensor harness connector.
5. Start engine and rev it (2,000 to 3,000 rpm) two or three times
under no load, then run engine at idle speed.
6. Check CO%.
7. After checking CO%, turn ignition switch OFF, disconnect the
resistor from the terminals of engine coolant temperature sensor
harness connector, and then connect engine coolant tempera-
ture sensor harness connector to engine coolant temperature
sensor.
OK or NG
OK >> GO TO 28.
NG >> GO TO 27.
27. RECONNECT AIR FUEL RATIO (A/F) SENSOR 1 HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Reconnect A/F sensor 1 harness connector.
>> GO TO 31.
28. REPLACE AIR FUEL RATIO (A/F) SENSOR 1
1. Stop engine.
2. Replace A/F sensor 1 on the malfunctioning bank.
With CONSULT-II>>GO TO 29.
Without CONSULT-II>>GO TO 30.Idle CO: 3 − 11% and engine runs smoothly.
SEF 1 72 Y
Idle CO: 3 − 11% and engine runs smoothly.
SEF 9 82 UA

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
Basic InspectionUBS00GZZ
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.
–Head lamp 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.
SEF 9 83 U
SEF 9 76 U
SEF 9 77 U

EC-638Revision: August 2007
EVAPORATIVE EMISSION SYSTEM
2004 QX56
WITH CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Also attach the pressure pump and hose to the EVAP service port adapter.
3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE” of “WORK SUPPORT
MODE” with CONSULT-II.
5. Touch “START”. A bar graph (Pressure indicating display) will
appear on the screen.
6. Apply positive pressure to the EVAP system until the pressure
indicator reaches the middle of the bar graph.
7. Remove EVAP service port adapter and hose with pressure
pump.
8. Locate the leak using a leak detector. Refer to EC-634, "
EVAP-
ORATIVE EMISSION LINE DRAWING" .
WITHOUT CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP ser-
vice port.
2. Also attach the pressure pump with pressure gauge to the EVAP
service port adapter.
PEF 8 38 U
PEF 9 17 U
SEF 2 00 U
SEF 4 62 UA

EM-100Revision: August 2007
SERVICE DATA AND SPECIFICATIONS (SDS)
2004 QX56
CAMSHAFT AND CAMSHAFT BEARING
Unit: mm (in)
*: Total indicator reading
Valve Lifter
Unit: mm (in)
Valve Clearance
Unit: mm (in)
*: Approximately 20°C (68 °F) ItemsStandard
Camshaft runout [TIR*] Less than 0.02 (0.0008)
Camshaft cam height “A” Intake & Exhaust 44.465 - 44.655 (1.7506 - 1.7581)
Cam wear limit0.02 (0.0008)
Outside diameter of camshaft journal 25.953 - 25.970 (1.0218 - 1.0224)
Camshaft bracket inside diameter 26.000 - 26.021 (1.0236 - 1.0244)
Camshaft journal clearance 0.030 - 0.068 (0.0012 - 0.0027)
Camshaft end play 0.115 - 0.188 (0.0045 - 0.0074)
Camshaft sprocket runout [TIR*] Less than 0.15 (0.0059)
SEM 67 1
ItemsStandard
Valve lifter diameter 33.977 - 33.987 (1.3377 - 1.3381)
Valve lifter hole diameter 34.000 - 34.016 (1.3386 - 1.3392)
Clearance between lifter and lifter guide 0.013 - 0.039 (0.0005 - 0.0015)
Items Hot Cold * (reference data)
Intake 0.304 - 0.416 (0.012 - 0.016) 0.26 - 0.34 (0.010 - 0.013)
Exhaust 0.308 - 0.432 (0.012 - 0.017) 0.29 - 0.37 (0.011 - 0.015)

SERVICE DATA AND SPECIFICATIONS (SDS)
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Revision: August 20072004 QX56
*: Total indicator reading
MAIN BEARING
Unit: mm (in) Main journal dia. “Dm” grade (No. 2, 3 and 4) StandardGrade No. A
Grade No. B
Grade No. C
Grade No. D
Grade No. E
Grade No. F
Grade No. G
Grade No. H
Grade No. J
Grade No. K
Grade No. L
Grade No. M
Grade No. N
Grade No. P
Grade No. R
Grade No. S
Grade No. T
Grade No. U
Grade No. V
Grade No. W
Grade No. X
Grade No. Y
Grade No. 1
Grade No. 263.963 - 63.964 (2.5182 - 2.5183)
63.962 - 63.963 (2.5182 - 2.5182)
63.961 - 63.962 (2.5181 - 2.5182)
63.960 - 63.961 (2.5181 - 2.5181)
63.959 - 63.960 (2.5181 - 2.5181)
63.958 - 63.959 (2.5180 - 2.5181)
63.957 - 63.958 (2.5180 - 2.5180)
63.956 - 63.957 (2.5179 - 2.5180)
63.955 - 63.956 (2.5179 - 2.5179)
63.954 - 63.955 (2.5179 - 2.5179)
63.953 - 63.954 (2.5178 - 2.5179)
63.952 - 63.953 (2.5178 - 2.5178)
63.951 - 63.952 (2.5178 - 2.5178)
63.950 - 63.951 (2.5177 - 2.5178)
63.949 - 63.950 (2.5177 - 2.5177)
63.948 - 63.949 (2.5176 - 2.5177)
63.947 - 63.948 (2.5176 - 2.5176)
63.946 - 63.947 (2.5176 - 2.5176)
63.945 - 63.946 (2.5175 - 2.5176)
63.944 - 63.945 (2.5175 - 2.5175)
63.943 - 63.944 (2.5174 - 2.5175)
63.942 - 63.943 (2.5174 - 2.5174)
63.941 - 63.942 (2.5174 - 2.5174)
63.940 - 63.941 (2.5173 - 2.5174)
Pin journal dia. “Dp” StandardGrade No. 0 53.968 - 53.974 (2.1247 - 2.1250)
Grade No. 1 53.962 - 53.968 (2.1245 - 2.1247)
Grade No. 2 53.956 - 53.962 (2.1243 - 2.1245)
Center distance “r”45.96 - 46.04 (1.8094 - 1.8126)
Out-of-round (Difference between X and Y)
Limit0.002 (0.0001)
Taper (Difference between A and B) 0.002 (0.0001)
Runout [TIR*]Less than 0.05 (0.002)
Crankshaft end playStandard 0.10 - 0.26 (0.0039 - 0.0102)
Limit 0.30 (0.0118)
Grade number UPR/LWR Thickness Identification color Remarks
PBIC0189E