Mitsubishi Lancer (4A9 engine). Manual — part 251

CAN-C Communication Circuit <Except for RALLIART>

ETACS-ECU

INTERFACE
CIRCUIT

CAN DRIVE
CIRCUIT

ASC-ECU

A/T-ECU

ABS-ECU

CVT-ECU

STEERING
WHEEL SENSOR
<AFS, ASC>

ENGINE-ECU

ELECTRIC
POWER
STEERING-ECU

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White
Y : Yellow SB : Sky blue BR : Brown O : Orange GR : Grey
R : Red P : Pink V : Violet PU : Purple SI : Silver

CORNER SENSOR/
BACK SENSOR-ECU

DIESEL

:

PETROL

:

1800-PETROL, 2000

:

NOTE

PETROL (EXCEPT SOHC)

:

VEHICLES WITHOUT ASC

:

VEHICLES WITH ASC

:

HEADLAMP
AUTOMATIC
LEVELLING-ECU

AS&G-ECU

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-28

AC801250

Connectors: A-04, A-58 <LHD>

AB

A-04 (B),
A-58 (B)

AC801253

AG

Connector: A-58 <RHD>

A-58 (B)

AC800715

Connectors: B-09, B-40

BC

B-09 (GR),
B-40 (B)

ACB02645

AE

C-03 (GR)

C-35

Connectors: C-03, C-35, C-40, C-124, C-127
<LHD>

C-40

C-127 (GR)

C-124 (GR)

ACB02648

AD

C-03 (GR)

C-114

C-35

Connectors: C-03, C-35, C-114, C-127 <RHD>

C-127 (GR)

ACB02646

AD

C-64

C-14

C-114

Connectors: C-14, C-64, C-114 <LHD>

ACB02647

AD

C-64

C-124 (GR)

C-04 (GR)

Connectors: C-14, C-64, C-124 <RHD>

AC612708 AW

Connector: C-211 <LHD>

AC612716 AX

Connectors: C-211 <RHD>

ACA00886

BE

Connector: C-301 <LHD>
ETACS-ECU

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-29

ACA00887

BF

Connector: C-301 <RHD>
ETACS-ECU

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-30

FUNCTION
If a line-to-line short is present in the CAN-C lines,
this diagnosis result will be set.

TROUBLE JUDGEMENT CONDITIONS
If only diagnosis code U0001 is set, the ETACS-ECU
determines that there is a failure.

TROUBLESHOOTING HINTS

• Malfunction of the connector (joint connectors or

ECU connectors improperly connected)

• Malfunction of the wiring harness (line-to-line

short in the CAN-C main or sub bus lines)

• Malfunction of the ECU (ECU on CAN-C lines

failed)

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-03 joint connector
(CAN2) and C-124 joint connector (CAN3)

CAUTION

The strand end of the twist wire should be within
10 cm from the connector. For details refer to .

Q: Is the check result normal?

YES <vehicles with ASC or AFS> :

Go to Step 2.

YES <vehicles without ASC and without AFS with
reversing sensor system> :

Go to Step 3.

YES <vehicles without ASC and without AFS
without reversing sensor system> :

Go to Step 4.

NO :

Repair the defective connector.

STEP 2. Check the wiring harness between C-211
steering wheel sensor connector and C-03 joint
connector (CAN2) for line-to-line short.

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 (CAN2), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-03 joint

connector terminal No.9 and 20.

OK: No continuity

Q: Is the check result normal?

YES <vehicles with reversing sensor system> :

Go

to Step 3.

YES <vehicles without reversing sensor system> :

Go to Step 4.

NO :

Go to Step 11.

STEP 3. Check the wiring harness between C-40
Corner sensor/back sensor-ECU connector and
C-03 joint connector (CAN2) for line-to-line short.

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 (CAN2), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-03 joint

connector terminal No.7 and 18.

OK: No continuity

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Go to Step 12.

STEP 4. Check the wiring harness between C-301
ETACS-ECU connector and C-03 joint connector
(CAN2) for line-to-line short.

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 (CAN2), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-03 joint

connector terminal No.11 and 22.

OK: No continuity

Q: Is the check result normal?

YES <vehicles with AFS> :

Go to Step 5.

YES <vehicles without AFS> :

Go to Step 6.

NO :

Go to Step 13.

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-31

STEP 5. Check the wiring harness between C-14
headlamp automatic levelling-ECU connector
and C-124 joint connector (CAN3) for line-to-line
short.

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 (CAN3), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-124

joint connector terminal No.7 and 18 <Petrol>.

OK: No continuity

(3) Check that there is continuity between C-124

joint connector terminal No.8 and 19 <Diesel>.

OK: No continuity

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Go to Step 14.

STEP 6. Check 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) for line-to-line
short.

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 (CAN3), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-124

joint connector terminal No.9 and 20.

OK: No continuity

Q: Is the check result normal?

YES <A/T or CVT> :

Go to Step 7.

YES <M/T (vehicles with electric power steering) > :

Go to Step 8.

YES <M/T (vehicles without electric power steering
with automatic stop & go (AS&G) system)> :

Go to

Step 9.

YES <M/T (vehicles without electric power steering
without automatic stop & go (AS&G) system)> :

Go to Step 10.

NO :

Go to Step 15.

STEP 7. Check 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) for line-to-line short.

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 (CAN3), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-124

joint connector terminal No.8 and 19.

OK: No continuity

Q: Is the check result normal?

YES <vehicles with electric power steering> :

Go

to Step 8.

YES <vehicles without electric power steering and
with automatic stop & go (AS&G) system> :

Go to

Step 9.

YES <vehicles without electric power steering and
without automatic stop & go (AS&G) system> :

Go

to Step 10.

NO :

Go to Step 16.

STEP 8. Check the wiring harness between C-114
electric power steering-ECU connector and C-
124 joint connector (CAN3) for line-to-line short.

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 (CAN3), and check

that there is continuity at the harness side.

(2) Check that there is continuity between C-124

joint connector terminal No.6 and 17 <Petrol>.

OK: No continuity

(3) Check that there is continuity between C-124

joint connector terminal No.7 and 18 <Diesel>.

OK: No continuity

Q: Is the check result normal?

YES <vehicles with automatic stop & go (AS&G)
system> :

Go to Step 9.

YES <vehicles without automatic stop & go (AS&G)
system> :

Go to Step 10.

NO :

Go to Step 17.