
IP-18
INSTRUMENT PANEL ASSEMBLY
Revision: August 20072004 QX56
1. Remove cup holder insert.
2. Release latch and remove rear console assembly.
3. Remove hinge cover.
4. Remove screws from hinge assembly and remove console lid assembly.
Remove hinge from upper console assembly.
Remove latch from lid assembly.
5. Remove screws and separate upper and lower console assemblies.
Remove floor latch from upper console assembly.
6. Remove screws and remove bin from upper console assembly.
7. Remove screws and remove floor base.
8. Remove bolts and remove floor bracket.
Assembly is in the reverse order of disassembly.

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
![INFINITI QX56 2004 Factory Service Manual PRECAUTIONS
LAN-3
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PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER INFINITI QX56 2004 Factory Service Manual PRECAUTIONS
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Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER](/manual-img/42/57034/w960_57034-2265.png)
PRECAUTIONS
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PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
UKS0017I
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.
WA RN ING:
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.
Precautions When Using CONSULT-IIUKS0017J
When connecting CONSULT-II to data link connector, connect them through CONSULT-II CONVERTER.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carry out CAN communication.
CHECK POINTS FOR USING CONSULT-II
1. Has CONSULT-II been used without connecting CONSULT-II CONVERTER on this vehicle?
–If YES, GO TO 2.
–If NO, GO TO 5.
2. Is there any indication other than indications relating to CAN communication system in the self-diagnosis
results?
–If YES, GO TO 3.
–If NO, GO TO 4.
3. Based on self-diagnosis results unrelated to CAN communication, carry out the inspection.
4. Malfunctions may be detected in self-diagnosis depending on control units carrying out CAN communica-
tion. Therefore, erase the self-diagnosis results.
5. Diagnose CAN communication system. Refer to LAN-5, "
CAN Communication Unit" .
Precautions For Trouble DiagnosisUKS0017K
CAN SYSTEM
Do not apply voltage of 7.0V or higher to the measurement terminals.
Use the tester with its open terminal voltage being 7.0V or less.
Be sure to turn ignition switch off and disconnect negative battery terminal before checking the circuit.
![INFINITI QX56 2004 Factory Service Manual LAN-22
[CAN]
CAN SYSTEM (TYPE 1)
Revision: August 20072004 QX56
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet. INFINITI QX56 2004 Factory Service Manual LAN-22
[CAN]
CAN SYSTEM (TYPE 1)
Revision: August 20072004 QX56
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet.](/manual-img/42/57034/w960_57034-2284.png)
LAN-22
[CAN]
CAN SYSTEM (TYPE 1)
Revision: August 20072004 QX56
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet. Refer to LAN-23, "
CHECK SHEET" .
NOTE:
If “NG” is displayed on “CAN COMM” as “CAN DIAG SUPPORT MONITOR” for the diagnosed control
unit, replace the control unit. Refer to AV- 1 3 1 , "
CAN Communication Line Check" .
9. According to the check sheet results (example), start inspection. Refer to LAN-25, "
CHECK SHEET
RESULTS (EXAMPLE)" .
![INFINITI QX56 2004 Factory Service Manual CAN SYSTEM (TYPE 1)
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Display Control Unit Circuit CheckUKS0018P
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the INFINITI QX56 2004 Factory Service Manual CAN SYSTEM (TYPE 1)
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Display Control Unit Circuit CheckUKS0018P
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the](/manual-img/42/57034/w960_57034-2307.png)
CAN SYSTEM (TYPE 1)
LAN-45
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Display Control Unit Circuit CheckUKS0018P
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check terminals and connector of display control unit for damage, bend and loose connection (control unit
side and harness side).
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect display control unit connector.
2. Check resistance between display control unit harness connec-
tor M95 terminals 25 (W) and 26 (R).
OK or NG
OK >> Replace display control unit.
NG >> Repair harness between display control unit and data
link connector.
BCM Circuit CheckUKS0018Q
1. CHECK CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect the negative battery terminal.
3. Check terminals and connector of BCM for damage, bend and loose connection (control module side and
harness side).
OK or NG
OK >> GO TO 2.
NG >> Repair terminal or connector.
2. CHECK HARNESS FOR OPEN CIRCUIT
1. Disconnect BCM connector.
2. Check resistance between BCM harness connector M18 termi-
nals 39 (W) and 40 (R).
OK or NG
OK >> Replace BCM. Refer to BCS-19, "Removal and Installa-
tion of BCM" .
NG >> Repair harness between BCM and data link connector.25 (W) - 26 (R) : Approx. 54 - 66Ω
SKIA6884E
39 (W) - 40 (R) : Approx. 54 - 66Ω
SKIA6869E
![INFINITI QX56 2004 Factory Service Manual CAN SYSTEM (TYPE 1)
LAN-49
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2. CHECK HARNESS FOR SHORT CIRCUIT
With all module and control unit connectors disconnected, check
continuity INFINITI QX56 2004 Factory Service Manual CAN SYSTEM (TYPE 1)
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2. CHECK HARNESS FOR SHORT CIRCUIT
With all module and control unit connectors disconnected, check
continuity](/manual-img/42/57034/w960_57034-2311.png)
CAN SYSTEM (TYPE 1)
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2. CHECK HARNESS FOR SHORT CIRCUIT
With all module and control unit connectors disconnected, check
continuity between data link connector M22 terminals 6 (W) and 14
(R).
OK or NG
OK >> GO TO 3.
NG >> Repair harness.
3. CHECK HARNESS FOR SHORT CIRCUIT
Check continuity between data link connector M22 terminals 6 (W),
14 (R) and ground.
OK or NG
OK >> Check ECM and IPDM E/R. Refer to LAN-49, "ECM/
IPDM E/R INTERNAL CIRCUIT INSPECTION" .
NG >> Repair harness.
IPDM E/R Ignition Relay Circuit CheckUKS0018X
Check the following. If no malfunction is found, replace the IPDM E/R.
IPDM E/R power supply circuit. Refer to PG-27, "IPDM E/R Power/Ground Circuit Inspection" .
Ignition power supply circuit. Refer to PG-13, "IGNITION POWER SUPPLY — IGNITION SW. IN ON
AND/OR START" .
Component InspectionUKS0018Y
ECM/IPDM E/R INTERNAL CIRCUIT INSPECTION
Remove ECM and IPDM E/R from vehicle.
Check resistance between ECM terminals 94 and 86.
Check resistance between IPDM E/R terminals 39 and 40.6 (W) - 14 (R) : Continuity should not exist.
PKIA2077E
6 (W) - Ground : Continuity should not exist.
14 (R) - Ground : Continuity should not exist.
PKIA2079E
Unit TerminalResistance value (Ω)
(Approx.)
ECM 94 - 86
108 - 132
IPDM E/R 39 - 40
LKIA0037E
![INFINITI QX56 2004 Factory Service Manual LAN-56
[CAN]
CAN SYSTEM (TYPE 2)
Revision: August 20072004 QX56
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet. INFINITI QX56 2004 Factory Service Manual LAN-56
[CAN]
CAN SYSTEM (TYPE 2)
Revision: August 20072004 QX56
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet.](/manual-img/42/57034/w960_57034-2318.png)
LAN-56
[CAN]
CAN SYSTEM (TYPE 2)
Revision: August 20072004 QX56
8. Mark the “NG” or “UNKWN” item of the check sheet table with “v” from the result of CAN DIAG SUPPORT
MONITOR check sheet. Refer to LAN-57, "
CHECK SHEET" .
NOTE:
If “NG” is displayed on “CAN COMM” as “CAN DIAG SUPPORT MONITOR” for the diagnosed control
unit, replace the control unit. Refer to AV- 1 3 1 , "
CAN Communication Line Check" .
9. According to the check sheet results (example), start inspection. Refer to LAN-59, "
CHECK SHEET
RESULTS (EXAMPLE)" .