Mitsubishi 380. Manual — part 650

EXPLANATION ABOUT THE DIAGNOSTIC TOOL (MUT-III) CAN BUS DIAGNOSTICS

CONTROLLER AREA NETWORK (CAN)

54C-11

NOTE: If you pinpoint trouble spot according to
DTC code, you should use time-out DTC code.
DTC code related to failure information is set
when the data to be set contains an error, so CAN
bus line itself is probably normal.

NOTE: Time-out DTC codes are stored in each
ECU memory individually. Therefore, it is possible
that these DTC codes have not been set simulta-
neously. If the trouble spot cannot be found when
you diagnose by judging from multiple DTC
codes, check the communication lines between
each ECU.

DTC CODE TO
BE SET

POSSIBLE
TROUBLE
SPOT

LOGIC FOR DETERMINING TROUBLE SPOT

Time-out DTC
code
associated with
ECU D is stored
in ECU A, ECU
B and ECU C

Trouble in
CAN bus line
(e) and power
supply system
to ECU D

When time-out DTC code
associated with ECU D is stored
in ECU A, B and C, or time-out
DTC code associated with ECUs
A, B and C is stored in ECU D, or
"bus off" DTC code is stored in
ECU D, CAN bus line (e) is
suspected. When DTC code is
not stored in ECU D, the power
supply to ECU D is suspected.

Time-out DTC
code
associated with
ECUs A, B and
C is stored in
ECU D

"Bus off" DTC
code is stored
in ECU D

AC204742 BD

DATA LINK

CONNECTOR

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

EXPLANATION ABOUT THE DIAGNOSTIC TOOL (MUT-III) CAN BUS DIAGNOSTICS

CONTROLLER AREA NETWORK (CAN)

54C-12

Time-out DTC
code
associated with
ECU A is stored
in ECUs B, C
and D

Trouble in
CAN bus line
(a) and power
supply system
to ECU A

When time-out DTC code
associated with ECU A is stored
in ECUs B, C and D, or time-out
DTC code associated with ECUs
B, C and D is stored in ECU A, or
"bus off" DTC code is stored in
ECU A, CAN bus line (a) or (c) is
suspected. When DTC code is
not stored in ECU A, the power
supply to ECU A is suspected.

Time-out DTC
code
associated with
ECUs B, C and
D is stored in
ECU A

"Bus off" DTC
code is stored
in ECU A

Time-out DTC
codes
associated with
ECUs C and D
are stored in
ECU A and
ECU B

Trouble in
CAN bus line
(d)

If time-out DTC codes associated
with ECUs C and D are stored in
ECUs A and B, or time-out codes
associated with ECUs A and B
are stored in ECUs C and D, CAN
bus line (d) is suspected. CAN
bus line (g) or (e) and power
supply systems to ECU C or D
are also suspected as second
cause.

Time-out DTC
codes
associated with
ECUs A and B
are stored in
ECU C and
ECU D

DTC CODE TO
BE SET

POSSIBLE
TROUBLE
SPOT

LOGIC FOR DETERMINING TROUBLE SPOT

AC204742 BE

DATA LINK

CONNECTOR

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

AC204742 BF

DATA LINK

CONNECTOR

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

AC204742BG

DATA LINK

CONNECTOR

ECU B

ECU C

ECU D

ECU A

(a)

(b)

(c)

(d)

(e)

(f)

(g)

DIAGNOSTIC TROUBLE CODE DIAGNOSIS

CONTROLLER AREA NETWORK (CAN)

54C-13

DIAGNOSTIC TROUBLE CODE DIAGNOSIS

M1548304500025

ON-BOARD DIAGNOSTICS

The CAN is a communication method which the
ECUs use in order to communicate each other. The
CAN-related diagnostic trouble codes will be stored
in the following ECUs, which use the CAN communi-
cation.

• Engine ECU

• A/T ECU

• ABS-ECU

• ETACS-ECU

• A/C-ECU

• SRS-ECU

• Combination meter

• Multi-center display

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

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. Ensure that the ignition switch is at the "LOCK" (OFF)

position.

2. Start up the personal computer.
3. Connect special tool MB991827 to special tool MB991824

and the personal computer.

4. Connect special tool MB991910 to special tool MB991824.
5. Connect special tool MB991910 to the data link connector.
6. Turn the power switch of special tool MB991824 to the "ON"

position.
NOTE: When special tool MB991824 is energised, special
tool MB991824 indicator lamp will be illuminated in a green
color.

7. Start the MUT-III system on the personal computer.
NOTE: Disconnecting diagnostic tool MB991958 is the reverse
of the connecting sequence, making sure that the ignition
switch is at the "LOCK" (OFF) position.

HOW TO DIAGNOSE THE CAN BUS LINE

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

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

DIAGNOSTIC TROUBLE CODE DIAGNOSIS

CONTROLLER AREA NETWORK (CAN)

54C-14

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 to the data link

connector.

2. Turn the ignition switch to the "ON" position.
3. Select "CAN bus diagnosis" from the start-up screen.
4. When the vehicle information is displayed, confirm that it

matches the vehicle whose CAN bus lines will be
diagnosed.

• If they match, go to step 8.

• If not, go to step 5.

5. Select the "view vehicle information" button.
6. Enter the vehicle information and select the "OK" button.
7. When the vehicle information is displayed, confirm again

that it matches the vehicle whose CAN bus lines will be
diagnosed.

• If they match, go to step 8.

• If not, go to step 5.

8. Select the "OK" button.
9. When the optional equipment screen is displayed, choose

the one which the vehicle is fitted with, and then select the
"OK" button.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827