2009 INFINITI QX56 ECU

LAN-18
< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
Interview Sheet (Example)
COLLECT DATA
Collect CONSULT-III Data
Print out or save the following CONSULT-III data.
• SELF-DIAG RESULTS
• CAN DIAG SUPPORT MNTR (“ECU list” included)
NOTE:
PKID1211E
Revision: December 20092009 QX56

LAN-20
< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
For some models, CAN communication diagnosis result is
received from the vehicle monitor. (CONSULT-III is
not available.)
CREATE DIAGNOSIS SHEET
NOTE:
Be sure to use the diagnosis sheet for the correct CAN system type.
Print Diagnosis Sheet
Print the diagnosis sheet for the applicable CAN system type.
Check Collected Data
Make sure that all ECUs are received, referring to “ECU list”.
SKIB8722E
Revision: December 20092009 QX56

LAN-22
< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
Identify the error circuit using information from t
he “CAN DIAG SUPPORT MNTR” (“ECU list” included).
1. ECU list: Check the items indicated in “ECU list”. Draw a line on the diagnosis sheet to indicate the error circuit.
NOTE:
CAN communication line has no error if units other than Diag on CAN units are not indicated. An error
may be on the power supply of the control unit, DDL1 line or DDL2 line.
a. “TCM” which is Diag on CAN unit, is not indicated on “E CU list”. This indicates that DLC is not receiving a
signal from TCM. Draw a line to indicate an error between DLC and TCM (line 1-a in the figure below).
NOTE:
• Diag on CAN units are not indicated on the “ECU list” when the CAN line between Diag on CAN unit and
the data link connector is open.
• For a description of Diag on CAN, refer to LAN-6, "
Description".
2. CAN DIAG SUPPORT MNTR: Check each item on “CAN DIAG SUPPORT MNTR”. Draw a line on the diagnosis sheet to indicate the error circuit.
a. Reception item of “ECM”: On “TCM”, “UNKWN” is indicated. This means ECM cannot receive the signal
from TCM. Draw a line to indicate an error between ECM and TCM (line 2-a in the figure below).
NOTE:
If “UNKWN” is indicated on “TRA NSMIT DIAG”, then the control uni t cannot transmit CAN communication
signal to each unit. Draw a line between the control unit and the splice.
b. Reception item of “AFS”: On “T CM”, “UNKWN” is indicated. This means AFS cannot receive the signal
from TCM. Draw a line to indicate an error between AFS and TCM (line 2-b in the figure below).
PKID1214E
Revision: December 20092009 QX56

LAN
DIAGNOSIS AND REPAIR WORKFLOWLAN-27
< BASIC INSPECTION > [CAN FUNDAMENTAL]
C
D
E
F
G H
I
J
K L
B A
O P
N
5. Perform the inspection for the detected error circui
t. For the inspection procedure, refer to “MALFUNC-
TION AREA CHART”.
Present Error — Short Circuit —
When the symptoms listed below exist, a short circui t of the CAN communication line is a possible cause.
Received data
Error symptom• Most the units connected to the CAN communication system go into fail-safe mode or are deactivated.
Inspection procedure
PKID1219E
Item (CONSULT-III) Indication
ECU list (on the CAN DIAG SUPPORT MNTR) A ll Diag on CAN units are not indicated.
CAN DIAG SUPPORT MNTR “UNKWN” is indicated under “TRANSMIT DIAG” and most reception items.
Revision: December 20092009 QX56

LAN-36
< HOW TO USE THIS MANUAL >[CAN]
HOW TO USE THIS SECTION
HOW TO USE THIS MANUAL
HOW TO USE THIS SECTION
CautionINFOID:0000000003894427
• This section describes information peculiar to a v
ehicle, sheets for trouble diagnosis, and inspection proce-
dures.
• For trouble diagnosis procedure, refer to LAN-14, "
Trouble Diagnosis Procedure".
Abbreviation ListINFOID:0000000003776444
Abbreviations in CAN communication signal chart, and the diagnosis sheet are as per the following list.
AbbreviationUnit nameSELECT SYSTEM
(CONSULT-III) CAN DIAG SUPPORT MNTR
(CONSULT-III)
4WD Transfer control unit ALL MODE AWD/4WDAWD/4WD
A-BAG Air bag diagnosis sensor unit AIR BAG—
ABS ABS actuator and electric unit (control unit) ABSVDC/TCS/ABS
ADP Driver seat control unit AUTO DRIVE POS.—
AV AV c o n t r o l u n i t M U LT I AVD I S P L AY
BCM BCM BCMBCM/SEC
DLC Data link connector ——
ECM ECM ENGINEECM
HVAC A/C auto amp. HVAC—
ICC ICC unit ICCICC
ICC/e4WD
I-KEY Intelligent Key unit INTELLIGENT KEYI-KEY
IPDM-E IPDM E/R IPDM E/RIPDM E/R
LASER ICC sensor —ICC SENSOR
M&A Combination meter METER/M&AMETER/M&A
STRG Steering angle sensor —STRG
TCM TCMTRANSMISSION TCM
Revision: December 20092009 QX56

LAN-62
< COMPONENT DIAGNOSIS >[CAN]
MAIN LINE BETWEEN TCM AND ADP CIRCUIT
• Decision of CAN system type.
• Not received CONSULT-III data [SELF-DIAG RESULTS, CAN DIAG SUPPORT MNTR (“ECU
list” included)].
• Procedure for detecting root cause.
YES (Past error)>>Error was detected in the main line between the TCM and the driver seat control unit.
NO >> Repair the main line between the harness connectors B40 and B37.
Revision: December 20092009 QX56

LAN
MAIN LINE BETWEEN TCM AND LASER CIRCUITLAN-63
< COMPONENT DIAGNOSIS > [CAN]
C
D
E
F
G H
I
J
K L
B A
O P
N
MAIN LINE BETWEEN TC
M AND LASER CIRCUIT
Diagnosis ProcedureINFOID:0000000003776463
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cabl e from the negative terminal.
3. Check the following terminals and connectors for damage, bend and loose connection (connector side
and harness side).
- Harness connector F14
- Harness connector E5
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair the terminal and connector.
2.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect the following harness connectors.
- A/T assembly
- Harness connectors F14 and E5
2. Check the continuity between the A/T asse mbly harness connector and the harness connector.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair the main line between the A/T assembly and the harness connector F14.
3.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect the connector of ICC sensor.
2. Check the continuity between the harness connector and the ICC sensor harness connector.
Is the inspection result normal?
YES (Present error)>>Check the following items again. • Decision of CAN system type.
• Not received CONSULT-III data [SELF-DIAG RESULTS, CAN DIAG SUPPORT MNTR (“ECU
list” included)].
• Procedure for detecting root cause.
YES (Past error)>>Error was detected in the main line between the A/T assembly and the ICC sensor.
NO >> Repair the main line between the harness connector E5 and the ICC sensor.
A/T assembly harness connector Harness connector
Continuity
Connector No. Terminal No.Connector No. Terminal No.
F9 3
F14 5
Existed
8 15Existed
Harness connector ICC sensor harness connector
Continuity
Connector No. Terminal No.Connector No. Terminal No.
E5 5
E42 2
Existed
15 3Existed
Revision: December 20092009 QX56

LAN-64
< COMPONENT DIAGNOSIS >[CAN]
MAIN LINE BETWEEN LASER AND ICC CIRCUIT
MAIN LINE BETWEEN LA
SER AND ICC CIRCUIT
Diagnosis ProcedureINFOID:0000000003776464
INSPECTION PROCEDURE
1.CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the following terminals and connectors for damage, bend and loose connection (connector side and harness side).
- Harness connector E34
- Harness connector B40
Is the inspection result normal?
YES >> GO TO 2.
NO >> Repair the terminal and connector.
2.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect the following harness connectors.
- ICC sensor
- Harness connectors E34 and B40
2. Check the continuity between the ICC sens or harness connector and the harness connector.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair the main line between the ICC sensor and the harness connector E34.
3.CHECK HARNESS CONTI NUITY (OPEN CIRCUIT)
1. Disconnect the connector of ICC unit.
2. Check the continuity between the harness connector and the ICC unit harness connector.
Is the inspection result normal?
YES (Present error)>>Check the following items again. • Decision of CAN system type.
• Not received CONSULT-III data [SELF-DIAG RESULTS, CAN DIAG SUPPORT MNTR (“ECUlist” included)].
• Procedure for detecting root cause.
YES (Past error)>>Error was detected in the ma in line between the ICC sensor and the ICC unit.
NO >> Repair the main line between the harness connector B40 and the ICC unit.
ICC sensor harness connector Harness connector
Continuity
Connector No. Terminal No.Connector No. Terminal No.
E42 2
E34 24
Existed
3 23Existed
Harness connector ICC unit harness connector
Continuity
Connector No. Terminal No.Connector No. Terminal No.
B40 24
B13 14
Existed
23 5Existed
Revision: December 20092009 QX56