2009 INFINITI QX56 200

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TROUBLE DIAGNOSISLAN-11
< FUNCTION DIAGNOSIS > [CAN FUNDAMENTAL]
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Example: CAN DIAG SUPPORT MNTR indication
Without PAST
With PAST
MONITOR ITEM (ON-BOARD DIAGNOSIS)
NOTE:
For some models, CAN communication diagnosis result is
received from the vehicle monitor. (CONSULT-III is
not available.)
PKID1075E
Item PRSNT Description
Initial diagnosis OK Normal at present
NG Control unit error (Except for some control units)
Transmission diagnosis OK Normal at present
UNKWN Unable to transmit signals for 2 seconds or more.
Diagnosis not performed
Control unit name
(Reception diagnosis) OK Normal at present
UNKWN Unable to receive signals for 2 seconds or more.
Diagnosis not performed
No control unit for receiving signals. (No applicable optional parts)
Item
PRSNT PAST Description
Transmission diagnosis OKOK Normal at present and in the past
1 – 39 Normal at present, but unable to transmit signals for 2 seconds or more
in the past. (The number indicates the number of ignition switch cycles
from OFF to ON.)
UNKWN 0 Unable to transmit signals for 2 seconds or more at present.
Control unit name
(Reception diagnosis) OK
OK Normal at present and in the past
1 – 39 Normal at present, but unable to receive signals for 2 seconds or more
in the past. (The number indicates the number of ignition switch cycles
from OFF to ON.)
UNKWN 0 Unable to receive signals for 2 seconds or more at present.
–– Diagnosis not performed.
No control unit for receiving signals. (No applicable optional parts)
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< FUNCTION DIAGNOSIS >[CAN FUNDAMENTAL]
TROUBLE DIAGNOSIS
Example: Vehicle Display
ItemResult indi-
cated Error counter
Description
CAN_COMM
(Initial diagnosis) OK
0 Normal at present
NG 1 – 50 Control unit error
(The number indicates how many times diagnosis has been
run.)
CAN_CIRC_1
(Transmission diagnosis) OK
0 Normal at present
UNKWN 1 – 50 Unable to transmit for 2 seconds or more at present.
(The number indicates how many times diagnosis has been
run.)
CAN_CIRC_2 – 9
(Reception diagnosis of each unit) OK
0 Normal at present
UNKWN 1 – 50 Unable to transmit for 2 seconds or more at present.
(The number indicates how many times diagnosis has been
run.)
Diagnosis not performed.
No control unit for receiving signals. (No applicable optional
parts)
Revision: December 20092009 QX56

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DIAGNOSIS AND REPAIR WORKFLOWLAN-13
< BASIC INSPECTION > [CAN FUNDAMENTAL]
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BASIC INSPECTION
DIAGNOSIS AND REPAIR WORKFLOW
Information Needed for Trouble DiagnosisINFOID:0000000003776439
CAN communication system performs trouble diagnosis with the following tools.
How to Use CAN Communication Signal ChartINFOID:0000000003776440
The CAN communication signal chart lists the signals needed for trouble diagnosis. It is useful for detecting
the root cause by finding a signal related to the sy
mptom, and by checking transmission and reception unit.
To o l U s a g e
Interview sheet For filling in vehicle information and interview with customer.
Data sheet For copying on-board diagnosis data.
Diagnosis sheet For detecting the root cause. (Diagnosis sheet includes system diagram for every CAN system type)
ECU list
(On the “CAN DIAG SUPPORT
MNTR”) For checking the condition of control units and the status of CAN communication.
SELF-DIAG RESULTS
(CONSULT-III)
CAN DIAG SUPPORT MNTR
(CONSULT-III)
CAN communication signal
chart For converting information received from a customer into CAN communication signal transmission
and reception. This information can be used to judge whether a circuit between control units is nor-
mal or abnormal.
Abbreviation list For checking abbreviations in CAN communication signal chart and diagnosis sheet.
SKIB8715E
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< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
Trouble Diagnosis Flow Chart
INFOID:0000000003776441
Trouble Diagnosis ProcedureINFOID:0000000003776442
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
PKID1210E
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DIAGNOSIS AND REPAIR WORKFLOWLAN-15
< BASIC INSPECTION > [CAN FUNDAMENTAL]
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• 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 to
the customer, and it performs CAN communication with many units.
INSPECTION OF VEHICLE CONDITION
• Check whether or not “U1000” or “U1001” is indi cated on “SELF-DIAG RESULTS” by CONSULT-III.
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:
• Do not turn the ignition switch OFF or disconnect the battery cable while 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 “DETECT THE ROOT CAUSE”.
CHECK OF CAN SYSTEM TYPE (HOW TO USE CAN SYSTEM TYPE SPECIFICATION CHART)
Determine CAN system type based on vehicle equipm ent. Then choose the correct diagnosis sheet.
NOTE:
There are two styles for CAN system type specificat ion 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:
SKIB8717E
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< BASIC INSPECTION >[CAN FUNDAMENTAL]
DIAGNOSIS AND REPAIR WORKFLOW
CAN system type is easily checked with the vehicle equi
pment identification information shown in the chart.
CAN System Type Specification Chart (Style B)
NOTE:
SKIB8888E
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CAN system type is easily checked wi
th the vehicle equipment identification information shown in the chart.
CREATE INTERVIEW SHEET
Fill out the symptom described by the customer, vehicle condition, and CAN system type on the interview
sheet.
SKIB8889E
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< 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