Mitsubishi Lancer (4A9 engine). Manual - part 273

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-116

connector (CAN1) terminal No.6 and body earth.

OK: 1 k

Ω or more

(3) Measure the resistance between C-04 joint 

connector (CAN1) terminal No.17 and body 
earth.

OK: 1 k

Ω or more

Q: Is the check result normal?

YES : 

Go to Step 10.

NO : 

Repair the wiring harness between C-103 
spare connector (for audio) and C-04 joint 
connector (CAN1).

STEP 10. Check the wiring harness between C-
301 ETACS-ECU connector and C-04 joint 
connector (CAN1) for short to earth (resistance 
measurement).

CAUTION

• Disconnect the negative battery terminal. For 

details refer to .

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

• Strictly observe the specified wiring harness 

repair procedure. For details refer to .

(1) Disconnect ETACS-ECU connector and joint 

connector (CAN1), and measure at the wiring 
harness side.

(2) Measure the resistance between C-04 joint 

connector (CAN1) terminal No.11 and body earth.

OK: 1 k

Ω or more

(3) Measure the resistance between C-04 joint 

connector (CAN1) terminal No.22 and body 
earth.

OK: 1 k

Ω or more

Q: Is the check result normal?

YES : 

Go to Step 27.

NO : 

Repair the wiring harness between C-301 
ETACS-ECU connector and C-04 joint 
connector (CAN1).

STEP 11. Check the wiring harness between C-
122 SRS connector and C-04 joint connector 
(CAN1) for short to power supply (voltage 
measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.10 and body 
earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.21 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES : 

Go to Step 12.

NO : 

Go to Step 20.

STEP 12. Check the wiring harness between C-60 
heater control unit connector <vehicles without 
A/C> or C-15 A/C-ECU connector <vehicles with 
A/C> and C-04 joint connector (CAN1) for short 
to power supply (voltage measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.8 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.19 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES : 

Go to Step 13.

NO : 

Go to Step 21.

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-117

STEP 13. Check the wiring harness between C-01 
combination meter connector and C-04 joint 
connector (CAN1) for short to power supply 
(voltage measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.9 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.20 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES <vehicles without KOS> : 

Go to Step 14.

YES <vehicles with KOS> : 

Go to Step 15.

NO (the check result is not normal.) : 

Go to Step 

22.

STEP 14. Check the wiring harness between C-06 
WCM connector and C-04 joint connector (CAN1) 
for short to power supply (voltage 
measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.7 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.18 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES <vehicles with radio and CD player> : 

Go to 

Step 16.

YES <vehicles with MMCS (vehicles for Russia)> : 

Go to Step 17.

YES <vehicles without MMCS and without radio 
and CD player> : 

Go to Step 18.

NO (the check result is not normal.) : 

Go to Step 

23.

STEP 15. Check the wiring harness between C-23 
KOS-ECU connector and C-04 joint connector 
(CAN1) for short to power supply (voltage 
measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.5 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.16 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES <vehicles with radio and CD player> : 

Go to 

Step 16.

YES <vehicles with MMCS (vehicles for Russia)> : 

Go to Step 17.

YES <vehicles without MMCS and without radio 
and CD player> : 

Go to Step 18.

NO (the check result is not normal.) : 

Go to Step 

24.

STEP 16. Check the wiring harness between C-
103 radio and CD player connector and C-04 joint 
connector (CAN1) for short to power supply 
(voltage measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-118

connector (CAN1) terminal No.6 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.17 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES : 

Go to Step 19.

NO : 

Go to Step 25.

STEP 17. Check the wiring harness between C-54 
CAN box unit connector and C-04 joint connector 
(CAN1) for short to power supply (voltage 
measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.6 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.17 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES : 

Go to Step 19.

NO : 

Go to Step 26.

STEP 18. Check the wiring harness between C-
103 spare connector (for audio) and C-04 joint 
connector (CAN1) for short to power supply 
(voltage measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

(1) Disconnect joint connector (CAN1), and measure 

at the wiring harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.6 and body earth.

OK: 5 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.17 and body 
earth.

OK: 5 V or less

Q: Is the check result normal?

YES : 

Go to Step 19.

NO : 

Repair the wiring harness between C-103 
spare connector (for audio) and C-04 joint 
connector (CAN1).

STEP 19. Check the wiring harness between C-
301 ETACS-ECU connector and C-04 joint 
connector (CAN1) for short to power supply 
(voltage measurement).

CAUTION

• A digital multimeter should be used. For 

details refer to .

• The test wiring harness should be used. For 

details refer to .

• Strictly observe the specified wiring harness 

repair procedure. For details refer to .

(1) Disconnect ETACS-ECU connector and joint 

connector (CAN1), and measure at the wiring 
harness side.

(2) Turn the ignition switch to the ON position.
(3) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.11 and body earth.

OK: 1 V or less

(4) Measure the voltage between C-04 joint 

connector (CAN1) terminal No.22 and body 
earth.

OK: 1 V or less

Q: Is the check result normal?

YES : 

Go to Step 27.

NO : 

Repair the wiring harness between C-301 
ETACS-ECU connector and C-04 joint 
connector (CAN1).

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-119

STEP 20. M.U.T.-III CAN bus diagnostics 
(checking the SRS-ECU for internal failure)

CAUTION

Strictly observe the specified wiring harness 
repair procedure. For details refer to .
Disconnect C-122 SRS-ECU connector, and diag-
nose the CAN bus line.

ACB01921AC

M.U.T.

JC

JC

SAS

AT/

CVT

EPS

ENGINE

ABS/

ASC

: Red section on screen

AS&G

ETACS

JC

KOS/
WCM

SRS

A/C

AUDIO

METER

MMCS

Levelling

Cor ner

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-122 

SRS-ECU connector and C-04 joint 
connector (CAN1).

NO : 

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

STEP 21. M.U.T.-III CAN bus diagnostics 
(checking the heater control unit <vehicles 
without A/C> or A/C-ECU <vehicles with A/C> for 
internal failure)

CAUTION

Strictly observe the specified wiring harness 
repair procedure. For details refer to .
Disconnect C-60 heater control unit connector <vehi-
cles without A/C> or C-15 A/C-ECU connector <vehi-
cles with A/C> connector, and diagnose the CAN bus 
line.

ACB01921AC

M.U.T.

JC

JC

SAS

AT/

CVT

EPS

ENGINE

ABS/

ASC

: Red section on screen

AS&G

ETACS

JC

KOS/
WCM

SRS

A/C

AUDIO

METER

MMCS

Levelling

Cor ner

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-60 

heater control unit connector <vehicles 
without A/C> or C-15 A/C-ECU connector 
<vehicles with A/C> and C-04 joint 
connector (CAN1).

NO : 

Check the heater control unit connector 
<vehicles without A/C> or A/C-ECU 
connector <vehicles with A/C> connector, 
and repair if necessary. If the heater control 
unit connector <vehicles without A/C> or A/
C-ECU connector <vehicles with A/C> is in 
good condition, replace the heater control 
unit <vehicles without A/C> or A/C-ECU 
<vehicles with A/C>.