Mitsubishi 380. Manual — part 10

DIAGNOSTIC TROUBLE CODE PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-37

STEP 3. Use diagnostic tool MB991958 to select "ECU
COMM Check" on the SWS monitor display.
Check the following ECUs:

• Sunroof-ECU

• ETACS-ECU

CAUTION

Connect special tool MB991910 before connecting special
tool MB991812. Be sure to connect special tool MB991806
after turning on special tool MB991824.
(1) Connect the SWS monitor. Refer to "How to connect SWS

monitor

P.54B-13

."

(2) Turn the ignition switch to the "LOCK" (OFF) position.
(3) Operate diagnostic tool MB991958 according to the

procedure below to display "ECU COMM Check."
a. Select "Interactive Diagnosis."
b. Select "System select."
c. Select "SWS."
d. Select "SWS MONITOR."
e. Select "ECU COMM Check."

(4) DIAGNOSTIC TOOL MB991958 should show "OK" on the

"ECU COMM Check" menus for both the "SUNROOF ECU"
and the "ETACS ECU" menus.

Q: Are "OK" displayed for both the "SUNROOF ECU" and

"ETACS ECU" menus?
"OK" are displayed for all the items : It is determined that

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

).

"NG" is displayed for the "SUNROOF ECU" menu :

Refer to Inspection Procedure A-5 "communication
with the sunroof-ECU is not possible

P.54B-87

."

"NG" is displayed for the "ETACS ECU" menu : Refer to

Inspection Procedure A-3 "Communication with the
ETACS-ECU is not possible

P.54B-74

."

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC302210

COLUMN SWITCH
CONNECTOR

COLUMN SWITCH
CONNECTOR AT
HARNESS SIDE

MB991812

AB

DIAGNOSTIC TROUBLE CODE PROCEDURES

SIMPLIFIED WIRING SYSTEM (SWS)

54B-38

DTC 010 (U1073): Bus Off

CAUTION

If DTC (U1073) is set in the ETACS-ECU, always
diagnose the CAN main bus line.

CAUTION

If the DTC is set as past trouble, the ECU cannot
be defective. Do not replace it.

.

TROUBLE JUDGMENT

DTC 010 (U1073) will be stored when the
ETACS-ECU ceases CAN communication (bus off)
and then resumes the communication by turning the
ignition switch to the "LOCK" (OFF) position

.

TECHNICAL DESCRIPTION (COMMENT)

Carry out diagnosis with particular emphasis on wir-
ing and connector(s) in the CAN bus lines. For diag-
nosis procedures, refer to "How to cope with past
trouble" (Refer to GROUP 00, How to treat past trou-
ble

P.00-16

).

.

TROUBLESHOOTING HINTS

• The wiring harness or connectors may have

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector.

• Refer to circuit diagrams GROUP-

90

• Refer to configuration diagrams GROUP-

80

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.

CAUTION

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

).

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

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

CAUTION

If DTC (U1100) or 012 is set in the ETACS-ECU,
always diagnose the CAN main bus line.

CAUTION

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

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

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.

CAUTION

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

).

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827