INFINITI FX35 2007 Service Manual

TROUBLE DIAGNOSES WORK FLOW LAN-17
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Revision: 2006 July 2007 FX35/FX45
Trouble Diagnosis ProcedureNKS004MJ
INTERVIEW WITH CUSTOMER
Interview with the customer is important to detect the root cause of CAN communication system errors and to
understand vehicle condition and symptoms for proper trouble diagnosis.
Points in interview

What: Parts name, system name

When: Date, Frequency

Where: Road condition, Place

In what condition: Driving condition/environment

Result: Symptom
NOTE:

Check normal units as well as error symptoms.
–Example: Circuit between ECM and the combination meter is judged normal if the customer indicates
tachometer functions normally.

When a CAN communication system error is present, multiple control units may malfunction or go into fail-
safe mode.

Indication of the combination meter is important to detect the root cause because it is the most obvious
from the customer, and it performs CAN communication with many units.
SKIB8717E

LAN-18
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TROUBLE DIAGNOSES WORK FLOW
Revision: 2006 July 2007 FX35/FX45
INSPECTION OF VEHICLE CONDITION

Check whether or not “U1000” or “U1001” is indicated on “SELF-DIAG RESULTS” by CONSULT-II.
NOTE:
Root cause cannot be detected using the procedure in this section if “U1000” or “U1001” is not indicated.

Check whether the symptom is reproduced or not.
NOTE:

Never turn the ignition switch OFF or disconnect the battery cable while the reproducing the error. The
error may temporarily correct itself, making it difficult to determine the root cause.

The procedures for present errors differ from the procedures for past errors. Refer to LAN-25,
"DETECT THE ROOT CAUSE" .

TROUBLE DIAGNOSES WORK FLOW LAN-19
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Revision: 2006 July 2007 FX35/FX45
CHECK OF CAN SYSTEM TYPE (HOW TO USE CAN SYSTEM TYPE SPECIFICATION CHART)
Determine CAN system type based on vehicle equipment. Then choose the correct diagnosis sheet.
NOTE:
There are two styles for CAN system type specification charts. Depending on the number of available system
types, either style A or style B may be used.
CAN System Type Specification Chart (Style A)
NOTE:
CAN system type is easily checked with the vehicle equipment identification information shown in the chart.
SKIB8888E

LAN-20
[CAN FUNDAMENTAL]
TROUBLE DIAGNOSES WORK FLOW
Revision: 2006 July 2007 FX35/FX45
CAN System Type Specification Chart (Style B)
NOTE:
CAN system type is easily checked with the vehicle equipment identification information shown in the chart.
SKIB8889E

TROUBLE DIAGNOSES WORK FLOW LAN-21
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Revision: 2006 July 2007 FX35/FX45
CREATE INTERVIEW SHEET
Fill out the symptom described by the customer, vehicle condition, and CAN system type on the interview
sheet.
Interview Sheet (Example)
SKIB8890E

LAN-22
[CAN FUNDAMENTAL]
TROUBLE DIAGNOSES WORK FLOW
Revision: 2006 July 2007 FX35/FX45
CREATE DATA SHEET
Create CONSULT-II Data Attachment Sheet
Print out the following CONSULT-II screens, and attach them to the CONSULT-II data attachment sheet.

SELECT SYSTEM

SELF-DIAG RESULTS

CAN DIAG SUPPORT MNTR
NOTE:
Some items may not be needed depending on CAN system type of vehicle.
SKIB8721E

TROUBLE DIAGNOSES WORK FLOW LAN-23
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Revision: 2006 July 2007 FX35/FX45
Create On-board Diagnosis Copy Sheet
Display the trouble diagnosis result of CAN communication with the on-board diagnosis function on the vehicle
monitor, etc. Copy them on the on-board diagnosis copy sheet.
NOTE:
For some models, CAN communication diagnosis result is received from the vehicle monitor. (CONSULT-II is
not available.)
SKIB8722E

LAN-24
[CAN FUNDAMENTAL]
TROUBLE DIAGNOSES WORK FLOW
Revision: 2006 July 2007 FX35/FX45
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 of Received Data
Check the created data sheet for missing information.

For abbreviations, refer to LAN-41, "Abbreviation List" .
SKIB8891E

TROUBLE DIAGNOSES WORK FLOW LAN-25
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Revision: 2006 July 2007 FX35/FX45
DETECT THE ROOT CAUSE
Identify the root cause using the created diagnosis sheet.
Identifying the root cause

Draw a line on the diagnosis sheet to indicate the possible cause. Narrow the search.
NOTE:

Color-code when drawing lines.

Do not draw a line onto a existing line.

Drawing a line is not necessary if the circuit is shorted. Refer to LAN-32, "Present Error — Short Circuit —
" , LAN-39, "Past Error — Short Circuit —" .
Refer to the following for details of the trouble diagnosis procedure.

LAN-26, "Present Error — Open Circuit —"

LAN-32, "Present Error — Short Circuit —"

LAN-33, "Past Error — Open Circuit —"

LAN-39, "Past Error — Short Circuit —"
NOTE:
When the root cause appears to be a branch line or short circuit, be sure to check the control unit as well as
the communication line.

LAN-26
[CAN FUNDAMENTAL]
TROUBLE DIAGNOSES WORK FLOW
Revision: 2006 July 2007 FX35/FX45
Present Error — Open Circuit —
Identify the error circuit using information from the “SELECT SYSTEM” and “CAN DIAG SUPPORT MNTR”
screens.
1. SELECT SYSTEM: Check the items indicated in “SELECT SYSTEM”. 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 indicated. An error may be
on the power supply of the control unit, DDL1 line or DDL2 line.
a. “TRANSMISSION” which is Diag on CAN unit, is not indicated on “SELECT SYSTEM” screen. This indi- cates 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).
NOTE:

Diag on CAN units are not indicated on the “SELECT SYSTEM” screen 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, "Diag on CAN" .
SKIB8892E