ecm INFINITI QX56 2010 Factory Service Manual

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Self-DiagnosisINFOID:0000000005152908
CAN Diagnostic Support MonitorINFOID:0000000005146447
CONSULT-III and CAN diagnostic support monitor (on-boar
d diagnosis function) are used for detecting root
cause.
MONITOR ITEM (CONSULT-III)
Example: CAN DIAG SUPPORT MNTR indication
Without PAST
DTC Self-diagnosis item
(CONSULT-III indication) DTC detection condition
Inspection/Action
U0101 LOST COMM (TCM) When ECM is not transmitting or receiving CAN commu-
nication signal of OBD (emission-related diagnosis) from
TCM for 2 seconds or more.
Start the inspection. Refer
to the applicable section
of the indicated control
unit.
U0140 LOST COMM (BCM)
When ECM is not transmitting or receiving CAN commu-
nication signal of OBD (emission-related diagnosis) from
BCM for 2 seconds or more.
U0164 LOST COMM (HVAC) When ECM is not transmitting or receiving CAN commu-
nication signal of OBD (emission-related diagnosis) from
A/C auto amp. or unified meter and A/C amp. for 2 sec-
onds or more.
U1000 CAN COMM CIRCUIT ECM
When ECM is not transmitting or receiving
CAN communication signal of OBD (emission-
related diagnosis) for 2 seconds or more.
Except
for ECM When a control unit (except for ECM) is not
transmitting or receiving CAN communication
signal for 2 seconds or more.
U1001 CAN COMM CIRCUIT When ECM is not transmitting or receiving CAN commu-
nication signal other than OBD (emission-related diagno-
sis) for 2 seconds or more.
U1002 SYSTEM COMM When a control unit is not transmitting or receiving CAN
communication signal for 2 seconds or less.
U1010 CONTROL UNIT(CAN) When an error is detected during the initial diagnosis for
CAN controller of each control unit. Replace the control unit
indicating “U1010” or
“P0607”.
P0607
ECM
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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:
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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).
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h. Reception item of “ABS”: “UNKWN” is not indicated. This indicates normal communication between ABS
and its receiving units. Do not draw any line.
i. Reception item of “IPDM-E”: “UNKWN” is not indicated. This indicates normal communication between IPDM-E and its receiving units. Do not draw any line.
3. Based on information received from “CAN DIAG SUPPORT MNTR”, place a check mark on the known good CAN communication line between ECM and IPDM-E.
a. Through the previous procedure, the circuit betw een ADP splice and TCM has the most amount of lines
(shade 3-a in the figure below).
b. Place a check mark on the known good lines to establish the error circuit.
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Reception item of “IPDM-E”: On “ECM”, “OK” is indicated. IPDM-E
communicates normally with ECM. Put
a check mark on the normal circuit between ECM and IPDM-E (check mark 3-b in the figure below).
4. Through the above procedure, the error is detected in the TCM branch line (shaded in the figure below). NOTE:
For abbreviations, refer to LAN-36, "
Abbreviation List".
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1. SELF-DIAG RESULTS: Inspect the control units
indicating “U1000” or “U1001” on SELF-DIAG RESULTS.
2. CAN DIAG SUPPORT MNTR (with PAST): Check the CAN DIAG SUPPORT MNTR (with PAST) of units indicating “U1000” or “U1001” on SELF-DIAG RESULTS. Draw a line on the diagnosis sheet to indicate
the possible error circuit.
NOTE:
For the details of each indication on CAN DIAG SUPPORT MNTR, refer to LAN-47, "
CAN Diagnostic Sup-
port Monitor".
a. Reception item of “ECM”: “VDC/TCS/ABS”, “3” is indicated in the “PAST”. This means ECM could not receive the signal from ABS in the past. Draw a line between ECM and ABS (line 2-a in the figure below).
b. Reception item of “M&A”: “VDC/TCS/ABS”, “3” is indicated in the “PAST”. This means M&A could not
receive the signal from ABS in the past. Draw a line between M&A and ABS (line 2-b in the figure below).
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c. Reception item of “TCM”: “VDC/TCS/ABS”, “3” is indicated in the “PAST”. This means TCM could not
receive the signal from ABS in the past. Draw a line between TCM and ABS (line 2-c in the figure below).
3. CAN DIAG SUPPORT MNTR (without PAST): Chec k the CAN DIAG SUPPORT MNTR (without PAST) of
units indicating “U1000” or “U1001” on SELF-DIAG RESULTS. Draw a line on the diagnosis sheet to indi-
cate the possible error circuit.
NOTE:
• While an error occurred in the past according to SE LF-DIAG RESULTS, it is unclear which signal is not
received. Assume that errors were detected from all reception items.
• Draw a single line among the unit and all reception it ems. (Work flow differs from CAN DIAG SUPPORT
MNTR (with PAST).)
a. Reception item of “EPS”: Assume that the unit could not receive the signals from ECM, ABS, and M&A. Draw a line among EPS, ECM, ABS, and M&A (line 3-a in the figure below).
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b. Reception item of “ABS”: Assume that the unit
could not receive the signal from ECM. Draw a line
between ABS and ECM (line 3-b in the figure below).
4. Search for the possible cause using CAN communication signal chart using information from the interview with the customer.
NOTE:
For the details of CAN communication signal, refer to LAN-44, "
CAN Communication Signal Chart".
a. ABS warning lamp turned ON and speedometer did not move: This means that “ABS warning lamp signal”
and “Vehicle speed signal” could not communicate between M&A and ABS (4-a in the figure below).
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b. The tachometer moved normally: This means that “Engine speed signal” could communicate normally
between ECM and M&A (4-b in the figure below).
5. Fill out the diagnosis sheet based on information from step 4.
a. The ABS warning lamp turned ON and speedometer did not move: Assume that a possible cause is no communication between M&A and ABS. Draw a line between M&A and ABS. (Line 5-a in the figure
below).
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b. The tachometer moved normally: Put check marks between ECM and M&A. The circuit between ECM and
M&A is functioning properly (check marks 5-b in the figure below).
6. The circuit which has the most amount of lines are the possible cause. Error is detected from ABS actua- tor and electric unit (control unit) branch line (shaded in the figure below).
NOTE:
For abbreviations, refer to LAN-36, "
Abbreviation List".
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