2004 INFINITI QX56 Combination

IDX-4
ALPHABETICAL INDEX
Driver air bag .................................................. SRS-45
DTC work support ............................................ EC-113
DTRL - Wiring diagram ....................................... LT-37
Duct and grilles .............................................. ATC-157
DVD Player ........................................................ AV-59
E
ECM input/output signal ..................................... EC-96
ECM power supply ............................. EC-128, EC-361
ECM relay ........................................................ EC-128
ECM/PW - Wiring diagram ............................... EC-362
ECTS - Wiring diagram .................................... EC-167
Electric sunroof .................................................. RF-10
Electric throttle control actuator ......... EC-365, EC-367
Electrical load signal circuit .............................. EC-612
Electrical units location ...................................... PG-64
Electronic ignition (EI) system ........................... EC-28
Engine control circuit diagram ........................... EC-94
Engine control component parts location ........... EC-88
Engine control module (ECM) .......................... EC-351
Engine control system diagram and chart ......... EC-23
Engine coolant .................................................... CO-8
Engine coolant temperature sensor (ECTS) ... EC-165,
EC-178
Engine fail-safe system ...................................... EC-77
Engine oil ............................................................. LU-7
Engine oil filter replacement ............................. MA-16
Engine oil precautions .......................................... GI-7
Engine oil replacement ..................................... MA-16
Engine removal ................................................. EM-70
Engine room cover ............................................ EM-11
Engine serial number .......................................... GI-48
ETC1 - Wiring diagram .................................... EC-368
ETC2 - Wiring diagram .................................... EC-375
ETC3 - Wiring diagram .................................... EC-379
EVAP canister .................................................. EC-636
EVAP canister purge volume control solenoid valve ....
EC-285
, EC-496
EVAP canister vent control valve ....... EC-292, EC-504
EVAP control system (small leak) diagnosis .. EC-276,
EC-316
, EC-324
EVAP control system pressure sensor .... EC-299, EC-
302, EC-308
EVAP control system purge flow monitoring diagnosis
EC-271
EVAP vapor lines inspection ............................. MA-19
Evaporative emission (EVAP) system ............. EC-633
Evaporator ..................................................... ATC-175
Exhaust manifold .............................................. EM-19
Exhaust system ................................................... EX-3
Exhaust system inspection .................................. EX-3
Expansion valve ............................................. ATC-177
F
F/FOG - Wiring diagram ..................................... LT-71
F/PUMP - Wiring diagram ................................ EC-602
Final drive pre-inspection .................. FFD-15, RFD-12
Final drive removal and installation ... FFD-12, RFD-10
Flow charts .......................................................... GI-27
Fluid temperature sensor (A/T) ........................ AT-131
Fluids ................................................................ MA-10
Fluorescent leak detector .............................. ATC-178
Fog lamp, front ................................................... LT-69
Foot lamp ......................................................... LT-129
Freeze frame data ............................... EC-54, EC-107
Front brake solenoid valve ................. AT-151, AT-154
Front bumper ...................................................... EI-13
Front case (Transfer) ....................................... TF-125
Front combination lamp removal and installation LT-33
Front door ............................. BL-129, BL-132, GW-69
Front Door Trim ................................................... EI-31
Front drive shaft (Transfer) .............................. TF-115
Front fog lamp .................................................... LT-69
Front passenger air bag .................................. SRS-50
Front seat ........................................................... SE-96
Front seat belt ...................................................... SB-3
Front seat belt pre-tensioner ............... SRS-3, SRS-57
Front washer ...................................................... WW-4
Front wiper ......................................................... WW-4
FTTS - Wiring diagram ...................... EC-227, EC-232
Fuel cut control (at no load high engine speed) EC-30
Fuel filter replacement ......................................... FL-5
Fuel gauge ............................................................ DI-5
Fuel injection system (Bank 1) .......... EC-208, EC-217
Fuel injection system (Bank 2) .......... EC-208, EC-217
Fuel injector and fuel tube ................................. EM-29
Fuel level sensor ................. EC-334, EC-336, EC-338
Fuel line inspection .............................................. FL-3
Fuel precautions ................................................... GI-5
Fuel pressure check .......................................... EC-46
Fuel pressure release ....................................... EC-46
Fuel pump ....................................................... EC-601
Fuel pump and gauge .......................................... FL-5
Fuel system .......................................................... FL-3
Fuel tank .............................................................. FL-9
Fuel tank temperature sensor ........... EC-225, EC-231
Fuel tank vacuum relief valve ......................... EC-636
FUELB1 - Wiring diagram ................. EC-210, EC-219
FUELB2 - Wiring diagram ................. EC-211, EC-220
Fuse ...................................................... PG-67, PG-77
Fuse and fusible link box .................................. PG-77
Fuse block ......................................................... PG-76
Fusible link ............................................ PG-67, PG-77
G
Garage jack and safety stand ............................. GI-40
Gauges ................................................................. DI-5
Generator .......................................................... SC-17
Generic scan tool (GST) ................................. EC-116
Glass ...................................... GW-11, GW-69, GW-72
Glove box lamp ................................... LT-152, LT-153
GPS antenna ..................................................... AV-62
Grease .............................................................. MA-10
Ground distribution ............................................ PG-30

IDX-7
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IDX
ALPHABETICAL INDEX
Rear axle ........................................................... RAX-5
Rear bumper ....................................................... EI-15
Rear case (Transfer) ........................................ TF-112
Rear combination lamp removal and installation ... LT-
122
Rear cover packing replacement diff. .............. RFD-23
Rear door ........................................... BL-129, GW-72
Rear seat ......................................................... SE-103
Rear seat belt ...................................................... SB-6
Rear suspension ............................................. RSU-25
Rear view monitor ............................................... DI-72
Rear washer .................................................... WW-33
Rear window defogger ..................................... GW-78
Rear wiper ....................................................... WW-33
Refrigerant connection precaution .................... ATC-7
Refrigerant discharging evacuating charging ATC-162
Refrigerant general precaution .......................... ATC-6
Refrigerant lines ........... ATC-162, ATC-170, ATC-171
Refrigerant pressure sensor ............ EC-607, ATC-173
Relay box .......................................................... PG-78
Remote keyless entry system ............................ BL-44
Removal and installation (A/T) ........... AT-255, AT-258
Removal and installation (Transfer) ................. TF-109
Revolution sensor (A/T) ................................... AT-112
Ring gear diff. inspection ................................. RFD-12
Road wheel size ................................................. GI-49
Rocker cover ..................................................... EM-33
Room lamp ....................................................... LT-129
Room lamp - See Interior lamp ........................ LT-129
ROOM/L - Wiring diagram ................................ LT-135
RP/SEN - Wiring diagram ............................... EC-608
S
SEAT - Wiring diagram ..................................... SE-88
Seat belt inspection ............................... SB-10, MA-31
Seat belt pre-tensioner .................................... SRS-57
Seat belt, front ..................................................... SB-3
Seat belt, rear ...................................................... SB-6
Seat, front .......................................................... SE-96
Seat, rear ........................................................ SE-103
Self-diagnosis (Transfer) .................................... TF-27
SEN/PW - Wiring diagram ............................... EC-425
SHIFT - Wiring diagram ................................... AT-237
Shift lock system .............................................. AT-236
Shock absorber (front) .................................... FSU-10
Shock absorber (rear) ..................................... RSU-34
Side air bag (satellite) sensor .......................... SRS-56
Side bearing preload diff. ................................ RFD-18
Side curtain air bag ......................................... SRS-53
Side trim .............................................................. EI-34
SMJ (super multiple junction) ............................ PG-74
SONAR - Wiring diagram .................................... DI-62
Spare tire size .................................................... GI-49
Spark plug ......................................................... EM-27
Spark plug replacement .................................... MA-17
Specification value .......................................... EC-123
Speedometer ......................................................... DI-5
Spiral cable ..................................................... SRS-47
SROOF - Wiring diagram .................................. RF-13
SRS - See Supplemental Restraint System ...... SRS-5
SRS - Wiring diagram ...................................... SRS-12
SRS Trouble diagnoses ..................................... SRS-8
Stabilizer bar (front) ......................................... FSU-12
Stabilizer bar (rear) ......................................... RSU-41
Stall test (A/T) .................................................... AT-58
Standardized relay ............................................. PG-72
START - Wiring diagram ................................... SC-11
Starting system .................................................. SC-10
Steering gear, linkage and transfer gear inspection .....
MA-28
Steering linkage ................................................. PS-15
Steering wheel and column ................................. PS-7
Step lamp ......................................................... LT-129
Stop lamp ......................................................... LT-103
Stop lamp switch ............................... EC-551, EC-621
STOP/L - Wiring diagram ................................. LT-104
Strut (front) ...................................................... FSU-10
Sun gear (Transfer) .......................................... TF-127
Sun roof, electric ................................................ RF-10
Sunload sensor .............................................. ATC-131
Sunroof .............................................................. RF-24
Supplemental Restraint System ........................ SRS-5
Supplemental restraint system - Wiring diagram . SRS-
12
Symbols and abbreviations ..................... GI-10, GI-22
Symptom matrix chart ........................................ EC-84
System readiness test (SRT) code .................... EC-55
T
T/TOW - Wiring diagram ................................... LT-126
Tachometer .......................................................... DI-5
Tail lamp ........................................................... LT-108
TAIL/L - Wiring diagram .................................... LT-111
TCM circuit diagram .......................................... AT-51
TCM inspection table ......................................... AT-90
TCS - Wiring diagram ..................................... BRC-16
TCS (traction control system) ........................... BRC-7
TCS component parts and connector location BRC-14
TCS wheel sensors ........................................ BRC-14
Thermometer ...................................................... DI-26
Three way catalyst ............................................. EM-19
Three way catalyst function (Bank 1) .............. EC-267
Three way catalyst function (Bank 2) .............. EC-267
Three way catalyst precautions ............................ GI-5
Throttle control motor ...................................... EC-378
Throttle control motor relay .............................. EC-373
Throttle position sensor (TPS) ... EC-171, EC-236, EC-
420, EC-422, EC-569
Throttle valve closed position learning .............. EC-44
Tie-rod ............................................................... PS-15
Timing chain ...................................................... EM-35
Tire rotation ....................................................... MA-27
Tire size .............................................................. GI-49
Tooth contact diff. ............................................ RFD-19
Torque converter installation AT-256, AT-257, AT-259,
AT-260

IP-6
SQUEAK AND RATTLE TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
73982-9E000: 45 mm (1.77 in) thick, 50 x 50 mm (1.97 x 1.97 in)/73982-50Y00: 10 mm (0.39 in) thick, 50 x 50
mm (1.97 x 1.97 in)
INSULATOR (Light foam block)
80845-71L00: 30 mm (1.18 in) thick, 30 x 50 mm (1.18 x 1.97 in)
FELT CLOTH TAPE
Used to insulate where movement does not occur. Ideal for instrument panel applications.
68370-4B000: 15 x 25 mm (0.59 x 0.98 in) pad/68239-13E00: 5 mm (0.20 in) wide tape roll
The following materials, not found in the kit, can also be used to repair squeaks and rattles.
UHMW (TEFLON) TAPE
Insulates where slight movement is present. Ideal for instrument panel applications.
SILICONE GREASE
Used in place of UHMW tape that will be visible or not fit.
Note: Will only last a few months.
SILICONE SPRAY
Use when grease cannot be applied.
DUCT TAPE
Use to eliminate movement.
CONFIRM THE REPAIR
Confirm that the cause of a noise is repaired by test driving the vehicle. Operate the vehicle under the same
conditions as when the noise originally occurred. Refer to the notes on the Diagnostic Worksheet.
Generic Squeak and Rattle TroubleshootingEIS00637
Refer to Table of Contents for specific component removal and installation information.
INSTRUMENT PANEL
Most incidents are caused by contact and movement between:
1. The cluster lid A and instrument panel
2. Acrylic lens and combination meter housing
3. Instrument panel to front pillar garnish
4. Instrument panel to windshield
5. Instrument panel mounting pins
6. Wiring harnesses behind the combination meter
7. A/C defroster duct and duct joint
These incidents can usually be located by tapping or moving the components to duplicate the noise or by
pressing on the components while driving to stop the noise. Most of these incidents can be repaired by apply-
ing felt cloth tape or silicone spray (in hard to reach areas). Urethane pads can be used to insulate wiring har-
ness.
CAUTION:
Do not use silicone spray to isolate a squeak or rattle. If you saturate the area with silicone, you will
not be able to recheck the repair.
CENTER CONSOLE
Components to pay attention to include:
1. Shifter assembly cover to finisher
2. A/C control unit and cluster lid C
3. Wiring harnesses behind audio and A/C control unit
The instrument panel repair and isolation procedures also apply to the center console.
DOORS
Pay attention to the:
1. Finisher and inner panel making a slapping noise
2. Inside handle escutcheon to door finisher
3. Wiring harnesses tapping
4. Door striker out of alignment causing a popping noise on starts and stops

INSTRUMENT PANEL ASSEMBLY
IP-11
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IP
Revision: August 20072004 QX56
1. Remove instrument lower cover LH. Refer to IP-13, "Instrument Lower Cover LH" .
2. Remove glove box assembly.
3. Remove center console lower covers.
4. Remove shift knob and A/T finisher. Refer to IP-13, "
A/T Finisher" .

Disconnect harness from bottom of A/T finisher.
5. Remove shifter assembly. Refer to AT-233, "
Control Device Removal and Installation" .

Disconnect harness and shifter cable.
6. Remove center console and disconnect harness.
7. Remove cluster lid C and disconnect harnesses.
8. Remove cluster lid D and disconnect harness.
9. Remove display assembly and the audio unit. Refer to AV-45, "
Removal and Installation for Audio Unit"
and AV- 1 5 8 , "Removal and Installation of Display Unit" .
10. Remove power point assemblies.
11. Remove front passenger air bag status light.
12. Remove hazard switch.
13. Remove clock.
14. Remove combination meter cover.
15. Remove cluster lid A and disconnect harness.
16. Remove combination meter and disconnect harness.
17. Remove lower knee protector LH.
18. Remove the upper and lower steering column covers.

Disconnect harness from ADP steering switch.
19. Remove defrost grille and disconnect optical sensor harness.
20. Remove side ventilator assembly LH.
21. Remove side ventilator assembly RH.
22. Remove instrument panel.

Remove passenger air bag nuts and remove air bag. Refer to SRS-50, "FRONT PASSENGER AIR
BAG MODULE" .

Disconnect GPS antenna.

Disconnect harnesses to instrument panel speakers LH and RH and remove speakers.

Disconnect all remaining harnesses.
Installation is in the reverse order of removal.
1. Steering member brackets 2. Bracket assembly LH 3. Steering member assembly
4. Combination meter cover 5. Defrost grille 6. Instrument panel speaker LH
7. Instrument panel 8. Bin mat 9. Side ventilator assembly LH
10. Instrument lower cover LH 11. Lower knee protector LH 12. Steering column cover upper
13. Steering column cover lower 14. Center console lower cover LH 15. Combination meter
16. Audio unit bracket LH 17. Driver instrument stay 18. Audio unit
19. Passenger instrument stay 20. Display assembly 21. Switch assembly
22. Cluster lid A 23. Cluster lid D ventilator LH 24. Front passenger air bag status light
25. Power point assemblies 26. Clock 27. Cluster lid C
28. Front air control 29. Audio control 30. Hazard switch
31. Cluster lid D ventilator RH 32. Cluster lid D 33. Glove box door
34. Glove box assembly 35. Glove box housing 36. Glove box striker
37. Rubber bumpers 38. Glove box damper 39. Audio unit bracket RH
40. Center console lower cover RH 41. Fuse block cover 42. Side ventilator assembly RH
43. Instrument panel bracket 44. Instrument panel speaker RH 45. Bracket assembly RH
46. Key cylinder escutcheon 47. Instrument lower cover RH

INSTRUMENT PANEL ASSEMBLY
IP-13
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IP
Revision: August 20072004 QX56
Instrument Lower Cover LH
Remove screws using power tool, and remove instrument lower
cover LH.

Pull to disconnect clips.

Disconnect harnesses from back of instrument lower cover LH.
Installation is in the reverse order of removal.
Combination Meter
1. Remove instrument lower cover LH. Refer to IP-13, "Instrument Lower Cover LH" .
2. Remove the combination meter cover.
3. Remove cluster lid A.
4. Remove screws using power tool and remove the combination
meter assembly.

Disconnect electrical connectors.
Installation is in the reverse order of removal.
A/T Finisher
1. Remove shift knob.
2. Remove console mask.
3. Pull up to release clips and remove A/T finisher.

Disconnect harnesses.
Installation is in the reverse order of removal.
Display Assembly and Audio Unit
1. Remove audio unit. Refer to AV- 4 5 , "Removal and Installation for Audio Unit" .
2. Remove display assembly. Refer to AV- 1 5 8 , "
Removal and Installation of Display Unit" .
LIIA1327E
LIIA1249E
LIIA1335E

LAN-1
LAN SYSTEM
K ELECTRICAL
CONTENTS
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SECTION LAN
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LAN
Revision: August 20072004 QX56
CAN
PRECAUTIONS .......................................................... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Precautions When Using CONSULT-II ..................... 3
CHECK POINTS FOR USING CONSULT-II ......... 3
Precautions For Trouble Diagnosis .......................... 3
CAN SYSTEM ....................................................... 3
Precautions For Harness Repair .............................. 4
CAN SYSTEM ....................................................... 4
CAN COMMUNICATION ............................................ 5
System Description .................................................. 5
CAN Communication Unit ........................................ 5
TYPE1 ................................................................... 5
TYPE2 ................................................................... 8
TYPE 3 ................................................................ 10
TYPE 4 ................................................................ 13
CAN SYSTEM (TYPE 1) ........................................... 16
System Description ................................................ 16
Component Parts and Harness Connector Location ... 16
Schematic .............................................................. 17
Wiring Diagram - CAN - ......................................... 18
Work Flow .............................................................. 21
CHECK SHEET ................................................... 23
CHECK SHEET RESULTS (EXAMPLE) ............. 25
Circuit Check Between TCM and Driver Seat Con-
trol Unit ................................................................... 40
Circuit Check Between Driver Seat Control Unit and
Data Link Connector .............................................. 41
Circuit Check Between Data Link Connector and
IPDM E/R ............................................................... 42
ECM Circuit Check ................................................. 43
TCM Circuit Check ................................................. 43
Driver Seat Control Unit Circuit Check ................... 44
Combination Meter Circuit Check .......................... 44
Display Control Unit Circuit Check ......................... 45
BCM Circuit Check ................................................. 45
Data Link Connector Circuit Check ........................ 46
Steering Angle Sensor Circuit Check ..................... 46Front Air Control Circuit Check ............................... 47
ABS Actuator and Electric Unit (Control Unit) Circuit
Check ..................................................................... 47
IPDM E/R Circuit Check ......................................... 48
CAN Communication Circuit Check ........................ 48
IPDM E/R Ignition Relay Circuit Check .................. 49
Component Inspection ............................................ 49
ECM/IPDM E/R INTERNAL CIRCUIT INSPEC-
TION .................................................................... 49
CAN SYSTEM (TYPE 2) ........................................... 50
System Description ................................................. 50
Component Parts and Harness Connector Location ... 50
Schematic ............................................................... 51
Wiring Diagram - CAN - .......................................... 52
Work Flow ............................................................... 55
CHECK SHEET ................................................... 57
CHECK SHEET RESULTS (EXAMPLE) ............. 59
Circuit Check Between TCM and ICC Sensor ........ 78
Circuit Check Between ICC Sensor and ICC Unit ... 79
Circuit Check Between ICC Unit and Driver Seat
Control Unit ............................................................. 80
Circuit Check Between Driver Seat Control Unit and
Data Link Connector ............................................... 80
Circuit Check Between Data Link Connector and
IPDM E/R ................................................................ 81
ECM Circuit Check ................................................. 82
TCM Circuit Check ................................................. 82
ICC Sensor Circuit Check ....................................... 83
ICC Unit Circuit Check ............................................ 83
Driver Seat Control Unit Circuit Check ................... 84
Combination Meter Circuit Check ........................... 84
Display Control Unit Circuit Check ......................... 85
BCM Circuit Check ................................................. 85
Data Link Connector Circuit Check ........................ 86
Steering Angle Sensor Circuit Check ..................... 86
Front Air Control Circuit Check ............................... 87
ABS Actuator and Electric Unit (Control Unit) Circuit
Check ..................................................................... 87
IPDM E/R Circuit Check ......................................... 88
CAN Communication Circuit Check ........................ 88

LAN-2Revision: August 20072004 QX56 IPDM E/R Ignition Relay Circuit Check ................... 89
Component Inspection ............................................ 89
ECM/IPDM E/R INTERNAL CIRCUIT INSPEC-
TION .................................................................... 89
CAN SYSTEM (TYPE 3) ........................................... 90
System Description ................................................. 90
Component Parts and Harness Connector Location ... 90
Schematic ............................................................... 91
Wiring Diagram - CAN - .......................................... 92
Work Flow ............................................................... 95
CHECK SHEET ................................................... 97
CHECK SHEET RESULTS (EXAMPLE) ............. 99
Circuit Check Between TCM and Driver Seat Con-
trol Unit .................................................................115
Circuit Check Between Driver Seat Control Unit and
Data Link Connector .............................................116
Circuit Check Between Data Link Connector and
IPDM E/R ..............................................................117
ECM Circuit Check ...............................................118
TCM Circuit Check ...............................................118
Driver Seat Control Unit Circuit Check .................119
Combination Meter Circuit Check .........................119
Display Control Unit Circuit Check ........................120
BCM Circuit Check ...............................................120
Data Link Connector Circuit Check .......................121
Steering Angle Sensor Circuit Check ...................121
Front Air Control Circuit Check .............................122
Transfer Control Unit Circuit Check ......................122
ABS Actuator and Electric Unit (Control Unit) Circuit
Check ...................................................................123
IPDM E/R Circuit Check .......................................123
CAN Communication Circuit Check ......................124
IPDM E/R Ignition Relay Circuit Check .................124
Component Inspection ..........................................125
ECM/IPDM E/R INTERNAL CIRCUIT INSPEC-
TION ..................................................................125CAN SYSTEM (TYPE 4) .......................................... 126
System Description ............................................... 126
Component Parts and Harness Connector Location . 126
Schematic ............................................................. 127
Wiring Diagram - CAN - ........................................ 128
Work Flow ............................................................. 131
CHECK SHEET ................................................. 133
CHECK SHEET RESULTS (EXAMPLE) ............ 135
Circuit Check Between TCM and ICC Sensor ...... 155
Circuit Check Between ICC Sensor and ICC Unit . 156
Circuit Check Between ICC Unit and Driver Seat
Control Unit ........................................................... 157
Circuit Check Between Driver Seat Control Unit and
Data Link Connector ............................................. 157
Circuit Check Between Data Link Connector and
IPDM E/R .............................................................. 158
ECM Circuit Check ................................................ 159
TCM Circuit Check ................................................ 159
ICC Sensor Circuit Check ..................................... 160
ICC Unit Circuit Check .......................................... 160
Driver Seat Control Unit Circuit Check .................. 161
Combination Meter Circuit Check ......................... 161
Display Control Unit Circuit Check ........................ 162
BCM Circuit Check ................................................ 162
Data Link Connector Circuit Check ....................... 163
Steering Angle Sensor Circuit Check .................... 163
Front Air Control Circuit Check ............................. 164
Transfer Control Unit Circuit Check ...................... 164
ABS Actuator and Electric Unit (Control Unit) Circuit
Check .................................................................... 165
IPDM E/R Circuit Check ........................................ 165
CAN Communication Circuit Check ...................... 166
IPDM E/R Ignition Relay Circuit Check ................. 166
Component Inspection .......................................... 167
ECM/IPDM E/R INTERNAL CIRCUIT INSPEC-
TION .................................................................. 167

CAN SYSTEM (TYPE 1)
LAN-31
[CAN]
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LAN
Revision: August 20072004 QX56
Case 7
Check combination meter circuit. Refer to LAN-44, "Combination Meter Circuit Check" .
PKIA8056E
PKIA8148E