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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-49
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the combination meter. On completion, verify
that the DTC is not reset.
NO : A poor connection, open circuit or other intermittent
malfunction is present in the CAN bus lines between
the combination meter and the ETACS-ECU (Refer to
GROUP 00, How to Cope with Intermittent
Malfunction P.00-14).
STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the ETACS-ECU. On completion, verify that
the DTC is not reset.
NO : A poor connection, open circuit or other intermittent
malfunction is present in the CAN bus lines between
the combination meter and the ETACS-ECU (Refer to
GROUP 00, How to Cope with Intermittent
Malfunction P.00-14).
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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-50
DTC 015 (U1111): Multi center Display Unit Time-out.
If DTC 015 (U1111) is set in the ETACS-ECU,
always diagnose the CAN main bus line.
Whenever the ECU is replaced, ensure that the
communication circuit is normal.
.
TROUBLE JUDGMENT
The ETACS-ECU receives multi center dis-
play-related signal from the multi center display . If
the ECU cannot receive the signal, DTC 015
( U 1111 ) w i l l b e s e t .
.
TECHNICAL DESCRIPTION (COMMENT)
Current trouble
Connector(s) or wiring harness in the CAN bus
lines between the multi center display unit and
the ETACS-ECU, the power supply system to the
multi center display unit , the multi center display
unit itself, or the ETACS-ECU may be defective.
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80Past trouble
If DTC 015 (U1111) is stored as a past trouble,
carry out diagnosis with particular emphasis on
wiring and connector(s) in the CAN bus line
between the multi center display unit and the
ETACS-ECU, and the power supply system to the
multi center display unit . For diagnosis proce-
dures, refer to "How to cope with past trouble"
(Refer to GROUP 00, How to treat past trouble
P.00-16).
NOTE: You cannot find a past trouble, by the
MUT-III CAN bus diagnostics even if there is a
failure in CAN bus lines. In this case, refer to
GROUP 00, How to Cope with Intermittent Mal-
function P.00-14 and check the CAN bus lines.
You can narrow down the possible cause of the
trouble by referring to the DTC, which is set
regarding the CAN communication-linked ECUs
(Refer to GROUP 54C, CAN Bus Line Diagnosis
P.54C-6).
.
TROUBLESHOOTING HINTS
The wiring harness or connectors may have
loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector
Malfunction of the multi center display
The ETACS-ECU may be defective
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: DIAGNOSTIC TOOL (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-51
STEP 1. Using diagnostic tool MB991958, diagnose the
CAN bus line.
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
(1) Connect diagnostic tool MB991958. Refer to "How to
connect SWS monitor P.54B-13."
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to GROUP 54C,
Diagnosis P.54C-13).
STEP 2. Using diagnostic tool MB991958, read the multi
center display diagnostic trouble code.
Check that the multi center display unit sets a DTC.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the multi center display DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the multi center display unit (Refer to
GROUP 54A, Diagnosis P.54A-256).
NO : Go to Step 3.
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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-52
STEP 3. Using diagnostic tool MB991958, read the A/C
diagnostic trouble code.
Check if a multi center display-related DTC is set in the A/C
system.
(1) Turn the ignition switch to the "ON" position.
(2) Check whether A/C system-related DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Go to Step 4.
NO : Go to Step 5.
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the multi center display . On completion,
verify that the DTC is not reset.
NO : A poor connection, open circuit or other intermittent
malfunction is present in the CAN bus lines between
the multi center display and the ETACS-ECU (Refer
to GROUP 00, How to Cope with Intermittent
Malfunction P.00-14).
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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-53
STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the ETACS-ECU. On completion, verify that
the DTC is not reset.
NO : A poor connection, open circuit or other intermittent
malfunction is present in the CAN bus lines between
the multi center display and the ETACS-ECU (Refer
to GROUP 00, How to Cope with Intermittent
Malfunction P.00-14).
DTC 021 (U1128): Failure Information on Combination Meter.
If DTC 021 (U1128) is set in the ETACS-ECU,
always diagnose the CAN main bus line.
Whenever the ECU is replaced, ensure that the
communication circuit is normal.
The combination meter- related DTC may be set
when DTC 021 (U1128) is set. (For details refer
to GROUP 00, Affiliated DTC Reference Table
P.00-17.) Diagnose the combination meter first
when the combination meter- related DTC is set.
.
TROUBLE JUDGMENT
The ETACS-ECU receives combination
meter-related signal from the combination meter via
the CAN bus lines. If a fail-safe related data is con-
tained in the signal from the combination meter,
DTC 021 (U1128) will be stored.
.
TECHNICAL DESCRIPTION (COMMENT)
Current trouble
The wiring harness wire or connectors may have
loose, corroded, or damage terminals, or termi-
nals pushed back in the connector, the Engine-
ECU, the combination meter or the ETACS-ECU
may be defective.
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-54
Past trouble
If DTC 021 (U1128) is stored as a past trouble,
carry out diagnosis with particular emphasis on
wiring and connector(s) in the CAN bus line
between the combination meter and the
ETACS-ECU, and the power supply system to the
combination meter. For diagnosis procedures,
refer to "How to cope with past trouble" (Refer to
GROUP 00, How to treat past trouble P.00-16).NOTE: You cannot find a past trouble, by the
MUT-III CAN bus diagnostics even if there is a
failure in CAN bus lines. In this case, refer to
GROUP 00, How to Cope with Intermittent Mal-
function P.00-14 and check the CAN bus lines.
You can narrow down the possible cause of the
trouble by referring to the DTC, which is set
regarding the CAN communication-linked ECUs
(Refer to GROUP 54C, CAN Bus Line Diagnos-
tics P.54C-6).
.
TROUBLESHOOTING HINTS
The ETACS-ECU may be defective
DIAGNOSIS
Required Special Tools:
MB991223: Harness Set
MB991958: DIAGNOSTIC TOOL (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
STEP 1. Using diagnostic tool MB991958, diagnose the
CAN bus line.
To prevent damage to diagnostic tool MB991958, always
turn the ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting diagnostic tool
MB991958.
(1) Connect diagnostic tool MB991958. Refer to "How to
connect SWS monitor P.54B-13."
(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES : Go to Step 2.
NO : Repair the CAN bus line (Refer to GROUP 54C,
Diagnosis P.54C-5).
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DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-55
STEP 2. Using diagnostic tool MB991958, read the Engine
ECU and A/T ECU diagnostic trouble code.
Check whether engine and automatic transaxle DTCs are set
or not.
(1) Turn the ignition switch to the "ON" position.
(2) Check for engine and automatic transaxle DTCs.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the Engine ECU (Refer to GROUP 13A,
Diagnosis P.13A-5), and GROUP 23A Automatic
transmission ECU, Diagnosis P.23A-12.
NO : Go to Step 3.
STEP 3. Using diagnostic tool MB991958, read the
combination meter diagnostic trouble code.
Check whether the combination meter-related DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check whether the combination meter-related DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Diagnose the combination meter (Refer to GROUP
54A, Diagnosis P.54A-46).
NO : Go to Step 4.
Page 56 of 1500
DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-56
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the ETACS-ECU. On completion, verify that
the DTC is not reset.
NO : There is an intermittent malfunction such as poor
engaged connector(s) or open circuit (Refer to
GROUP 00, How to Cope with Intermittent
Malfunction P.00-14).