check engine MITSUBISHI 380 2005 Workshop Manual

SWS DIAGNOSIS
SIMPLIFIED WIRING SYSTEM (SWS)54B-10
SWS DIAGNOSIS
GENERAL DESCRIPTION
BEFORE CARRYING OUT TROUBLESHOOTINGM1549014700710
Before carrying out troubleshooting, check the fol-
lowing two items.
Make sure that the ETACS-ECU, the junction
block (J/B), the front-ECU and the engine com-
partment relay box are connected securely.
Make sure that fuses and fusible links related to
relevant systems are not blown.
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80
DIAGNOSTIC FUNCTIONM1549028900245
ON-BOARD DIAGNOSTICS
If an error occurs in the ECU or the SWS or CAN
communication line which performs the SWS or CAN
communication, the DTC is memorized in
ETACS-ECU. The DTCs have 11 items. The DTCs
are checked to connect diagnostic tool MB991958
(MUT-III sub assembly). The memorised DTCs are
not erased even if the ignition switch is turned to the
LOCK (OFF) position. The DTCs are erased to oper-
ate diagnostic tool MB991958 (MUT-III sub assem-
bly).NOTE:
*1: For vehicles that do not have a sunroof,
the diagnosis code is always sent but it does not indi-
cate a problem.
NOTE:
*2: The diagnosis code for the current prob-
lem is not sent.
NOTE:
*3: For vehicles that do not have a multi cen-
ter display (middle grade type), the diagnosis code is
always sent but it does not indicate a problem.
HOW TO CONNECT THE DIAGNOSTIC TOOL
(MUT-III)
Required Special Tools:
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 DTC CODE TROUBLE CONTENT
001 or U1700 Malfunction of SWS communication line or ETACS-ECU
002 or U1701 Malfunction of column switch
003 or U1702 Malfunction of front-ECU
004
*1 or U1073Malfunction of sunroof-ECU
010
*2 or U1073Bus Off
011 or U1100 Engine ECU time-out
012 or U1101 A/T ECU time-out
013 or U1110 A/C-ECU time-out
014 or U1108 Combination meter time-out
015
*3 or U1111Multi center display unit time-out
021 or U1128 Failure information on combination meter

DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-39
STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Replace the ETACS-ECU. After replacement, 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).
DTC 011 (U1100): Engine ECU Time-out
DTC 012 (U1101): A/T ECU Time-out
If DTC (U1100) or 012 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
DTC 011 (U1100)
The ETACS-ECU receives engine control sys-
tem-related signal from the Engine ECU. If the
ECU cannot receive the signal, DTC 011
(U1100) will be set. DTC 012 (U1101)
The ETACS-ECU receives automatic transaxle
control system-related signal from the A/T ECU.
If automatic transaxle control system-related sig-
nal cannot be received, DTC 012 (U1101) will be
set.
.
TECHNICAL DESCRIPTION (COMMENT)
Current trouble
Connector(s) or wiring harness in the CAN bus
lines between the Engine ECU or A/T ECU and
the ETACS-ECU, the power supply system to the
Engine ECU or A/T ECU, the Engine ECU or A/T
ECU itself, or the ETACS-ECU may be defective.
Refer to circuit diagrams GROUP-90
Refer to configuration diagrams GROUP-80

DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-40
Past trouble
If DTC (U1100) or 012 is stored as a past trouble,
carry out diagnosis with particular emphasis on
wiring and connector(s) in the CAN bus line
between the ETACS-ECU and the Engine ECU or
A/T ECU , and the power supply system to the
Engine ECU or A/T ECU. 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 Diagnostic
Flow 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.
The Engine ECU or A/T ECU may be defective.
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).

DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-41
STEP 2. Using diagnostic tool MB991958, read the Engine
ECU or 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), or Diagnose the A/T-ECU (refer
to GROUP 23A, Diagnosis P.23A-12).
NO : Go to Step 3.
STEP 3. Using diagnostic tool MB991958, read the for any
diagnostic trouble code.
Check if a DTC, which relates to CAN communication-linked
systems below, is set.
Combination meter
DTC indicating a time-out error related to the engine or
automatic transaxle control system
A/C
DTC indicating a time-out error related to the engine or
automatic transaxle control system
(1) Turn the ignition switch to the "ON" position.
(2) Check for a DTC related to the relevant system.
(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.

DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-42
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 Engine 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 Engine-ECU 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 Engine ECU or A/T ECU and the ETACS-ECU
(Refer to GROUP 00, How to Cope with Intermittent
Malfunction P.00-14).

DIAGNOSTIC TROUBLE CODE PROCEDURES
SIMPLIFIED WIRING SYSTEM (SWS)54B-48
STEP 2. 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-45).
NO : Go to Step 3.
STEP 3. Using diagnostic tool MB991958, read the for any
diagnostic trouble code.
Check if a DTC, which relates to CAN communication-linked
systems below, is set.
Engine
Meter-related time-out DTC
Multi center display
Meter-related time-out DTC
(1) Turn the ignition switch to the "ON" position.
(2) Check for a DTC related to the relevant system.
(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.

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

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.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-12
STEP 3. Using diagnostic tool , check data list item 59:
Inside temperature sensor.
To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
(1) Connect diagnostic tool to the data link connector.
(2) Start the engine.
(3) Set diagnostic tool to the data reading mode for item 59:
Inside temperature sensor.
Check that the interior temperature matches the dis-
played value on the diagnostic tool.
NOTE: When this DTC is set and the system is in fail-safe
status, the value of service data displays 25
C.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Does the interior temperature match the displayed value
on the diagnostic tool?
YES : Replace the A/C-ECU. Then go to Step 7.
NO : Go to Step 4.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-18
STEP 3. Using diagnostic tool , check data list item 58:
Outside air temperature sensor.
To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
(1) Connect diagnostic tool to the data link connector.
(2) Start the engine.
(3) Set diagnostic tool to the data reading mode for item 58:
Outside air temperature sensor.
Check that the ambient temperature matches the dis-
played value on the diagnostic tool.
NOTE: When this DTC is set and the system is fail-safe sta-
tus, the value of service data displays 20
C.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor within the specified range?
YES : Replace the A/C-ECU. Then go to Step 8.
NO : Go to Step 4.
STEP 4. Check ambient air temperature sensor connector
A-25 for loose, corroded or damaged terminals, or
terminals pushed back in the connector.
Q: Is ambient air temperature sensor connector A-25 in
good condition?
YES : Go to Step 5.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. Then go
to Step 8.