Mitsubishi Lancer (4A9 engine). Manual — part 255

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-44

<CAN_H>

OK: 1 k

Ω or more

(3) Measure the resistance between C-03 joint

connector (CAN2) terminal No.22 and body
earth. <CAN_L>

OK: 1 k

Ω or more

Q: Is the check result normal?

YES :

Check the ETACS-ECU connector, and

repair if necessary. If the ETACS-ECU
connector is in good condition, replace the
ETACS-ECU.

NO :

Repair the wiring harness between C-301
ETACS-ECU connector and C-03 joint
connector (CAN2).

STEP 13. M.U.T.-III CAN bus diagnostics
(checking the headlamp automatic levelling-ECU
for internal short to earth)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect C-14 headlamp automatic levelling-ECU
connector, and diagnose the CAN bus line.

ACB01921AB

M.U.T.

JC

JC

SAS

KOS/
WCM

SRS

A/C

AUDIO

METER

AT/

CVT

EPS

ENGINE

ETACS

ABS/

ASC

MMCS

: Red section on screen

AS&G

Levelling

Cor ner

JC

OK: The display of the M.U.T.-III is as shown
in the figure.

Q: Does M.U.T.-III screen correspond to the

illustration?
YES :

Repair the wiring harness between C-14

headlamp automatic levelling-ECU
connector and C-124 joint connector
(CAN3).

NO :

Check the C-14 headlamp automatic
levelling-ECU connector, and repair if
necessary. If the C-14 headlamp automatic
levelling-ECU connector is in good
condition, replace the C-14 headlamp
automatic levelling-ECU.

STEP 14. M.U.T.-III CAN bus diagnostics
(checking the ABS-ECU <vehicles without ASC>
or ASC-ECU <vehicles with ASC> for internal
short to earth)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect A-04 ABS-ECU connector <vehicles
without ASC> or A-58 ASC-ECU connector <vehi-
cles with ASC>, and diagnose the CAN bus line.

ACB01921AB

M.U.T.

JC

JC

SAS

KOS/
WCM

SRS

A/C

AUDIO

METER

AT/

CVT

EPS

ENGINE

ETACS

ABS/

ASC

MMCS

: Red section on screen

AS&G

Levelling

Cor ner

JC

OK: The display of the M.U.T.-III is as shown
in the figure.

Q: Does M.U.T.-III screen correspond to the

illustration?
YES :

Repair the wiring harness between A-04

ABS-ECU connector <vehicles without
ASC> or A-58 ASC-ECU connector
<vehicles with ASC> and C-124 joint
connector (CAN3).

NO :

Check the ABS-ECU connector <vehicles
without ASC> or ASC-ECU connector
<vehicles with ASC>, and repair if
necessary. If the ABS-ECU connector
<vehicles without ASC> or ASC-ECU
connector <vehicles with ASC> is in good
condition, replace the ABS-ECU <vehicles
without ASC> or ASC-ECU <vehicles with
ASC>.

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-45

STEP 15. M.U.T.-III CAN bus diagnostics
(checking the A/T-ECU <A/T> or CVT-ECU <CVT>
for internal short to earth)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect C-32 A/T-ECU connector <A/T> or C-35
CVT-ECU connector <CVT>, and diagnose the CAN
bus line.

ACB01921AB

M.U.T.

JC

JC

SAS

KOS/
WCM

SRS

A/C

AUDIO

METER

AT/

CVT

EPS

ENGINE

ETACS

ABS/

ASC

MMCS

: Red section on screen

AS&G

Levelling

Cor ner

JC

OK: The display of the M.U.T.-III is as shown
in the figure.

Q: Does M.U.T.-III screen correspond to the

illustration?
YES :

Repair the wiring harness between C-32 A/

T-ECU connector <A/T> or C-35 CVT-ECU
connector <CVT> and C-124 joint connector
(CAN3).

NO :

Check the A/T-ECU connector <A/T> or
CVT-ECU connector <CVT>, and repair if
necessary. If the A/T-ECU connector <A/T>
or CVT-ECU connector <CVT> is in good
condition, replace the A/T-ECU connector
<A/T> or CVT-ECU connector <CVT>.

STEP 16. M.U.T.-III CAN bus diagnostics
(checking the electric power steering-ECU for
internal short to earth)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect C-114 electric power steering-ECU con-
nector, and diagnose the CAN bus line.

ACB01921AB

M.U.T.

JC

JC

SAS

KOS/
WCM

SRS

A/C

AUDIO

METER

AT/

CVT

EPS

ENGINE

ETACS

ABS/

ASC

MMCS

: Red section on screen

AS&G

Levelling

Cor ner

JC

OK: The display of the M.U.T.-III is as shown
in the figure.

Q: Does M.U.T.-III screen correspond to the

illustration?
YES :

Repair the wiring harness between C-114

electric power steering-ECU connector and
C-124 joint connector (CAN3).

NO :

Check the electric power steering-ECU
connector, and repair if necessary. If the
electric power steering-ECU connector is in
good condition, replace the electric power
steering-ECU.

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-46

STEP 17. M.U.T.-III CAN bus diagnostics
(checking the AS&G-ECU for internal short to
earth)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect C-64 AS&G-ECU connector, and diag-
nose the CAN bus line.

ACB01921AB

M.U.T.

JC

JC

SAS

KOS/
WCM

SRS

A/C

AUDIO

METER

AT/

CVT

EPS

ENGINE

ETACS

ABS/

ASC

MMCS

: Red section on screen

AS&G

Levelling

Cor ner

JC

OK: The display of the M.U.T.-III is as shown
in the figure.

Q: Does M.U.T.-III screen correspond to the

illustration?
YES :

Repair the wiring harness between C-64

AS&G-ECU connector and C-124 joint
connector (CAN3).

NO :

Check the AS&G-ECU connector, and
repair if necessary. If the C-64 AS&G-ECU
connector is in good condition, replace the
AS&G-ECU.

STEP 18. M.U.T.-III CAN bus diagnostics
(checking the engine-ECU for internal short to
earth)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect B-09 <Petrol> or B-40 <Diesel> engine-
ECU connector, and diagnose the CAN bus line.

ACB01921AB

M.U.T.

JC

JC

SAS

KOS/
WCM

SRS

A/C

AUDIO

METER

AT/

CVT

EPS

ENGINE

ETACS

ABS/

ASC

MMCS

: Red section on screen

AS&G

Levelling

Cor ner

JC

OK: The display of the M.U.T.-III is as shown
in the figure.

Q: Does M.U.T.-III screen correspond to the

illustration?
YES :

Repair the wiring harness between B-09

<Petrol> or B-40 <Diesel> engine-ECU
connector and C-124 joint connector
(CAN3).

NO :

Check the engine-ECU connector, and
repair if necessary. If the engine-ECU
connector is in good condition, replace the
engine-ECU.

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-47

Diagnosis Item 5: Diagnose shorts in the power supply to CAN-C bus line

CAUTION

When servicing a CAN bus line, earth yourself by touching a metal object such as an unpainted water
pipe. If you fail to do, a component connected to the CAN bus line may be broken.