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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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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.
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• Refer to “MALFUNCTION AREA CHART”.
Past Error — Open Circuit —
Review CAN communication signal chart based on information received from the interview with the customer
and on past error information from SELF-DIAG RESULTS and CAN DIAG SUPPORT MNTR.
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1. SELF-DIAG RESULTS: Inspect the control units
indicating “U1000” or “U1001” on S INFINITI QX56 2008 Factory Service Manual LAN
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1. SELF-DIAG RESULTS: Inspect the control units
indicating “U1000” or “U1001” on S](/manual-img/42/57030/w960_57030-2523.png)
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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 t INFINITI QX56 2008 Factory Service Manual LAN-30
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c. Reception item of “TCM”: “VDC/TCS/ABS”, “3” is indicated in the “PAST”. This means TCM could not
receive t](/manual-img/42/57030/w960_57030-2524.png)
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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".
SKIB8735E
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