Mitsubishi Lancer (4A9 engine). Manual — part 259

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-60

Diagnosis Item 7: Diagnose when the M.U.T.-III cannot receive the data sent by corner sensor/back
sensor-ECU <Vehicles with reversing sensor system>

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.

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-61

ACB02645

AF

C-03 (GR)

Connectors: C-03, C-40

C-40

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-62

FUNCTION
If the M.U.T.-III cannot communicate with the corner
sensor/back sensor-ECU, this diagnosis result will be
set.

TROUBLE JUDGEMENT CONDITIONS
If a communication flag is not set for the corner sen-
sor/back sensor-ECU, the ETACS-ECU determines
that there is a failure.

TROUBLESHOOTING HINTS

• Malfunction of the connector [joint connector

(CAN2) or corner sensor/back sensor-ECU con-
nector improperly connected]

• Malfunction of the wiring harness [open circuit

between the corner sensor/back sensor-ECU and
the joint connector (CAN2), power supply circuit
to the corner sensor/back sensor-ECU]

• Malfunction of the corner sensor/back sensor-

ECU

DIAGNOSIS PROCEDURE

STEP 1. Connector check: C-40 corner sensor/
back sensor-ECU connector and C-03 joint
connector (CAN2)

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 :

Go to Step 2.

NO :

Repair the defective connector.

STEP 2. Check the wiring harness between C-40
corner sensor/back sensor-ECU connector and
C-03 joint connector (CAN2)

CAUTION

Strictly observe the specified wiring harness
repair procedure. For details refer to .
Disconnect corner sensor/back sensor-ECU connec-
tor and joint connector (CAN2), and check the follow-
ing wiring harness.
(1) Check that there is continuity between C-40

corner sensor/back sensor-ECU connector
terminal No.19 and C-03 joint connector (CAN2)
terminal No.7 <CAN_H>

OK: Continuity exists (2

Ω or less)

(2) Check that there is continuity between C-40

corner sensor/back sensor-ECU connector
terminal No.20 and C-03 joint connector (CAN2)
terminal No.18 <CAN_L>

OK: Continuity exists (2

Ω or less)

Q: Is the check result normal?

YES :

Check the power supply circuit of the corner

sensor/back sensor-ECU. Refer to Group
54A

− Troubleshooting .

NO :

Repair the wiring harness.

TROUBLESHOOTING

CONTROLLER AREA NETWORK (CAN)

54C-63

Diagnosis Item 8: Diagnose when the M.U.T.-III cannot receive the data sent by ABS-ECU <vehicles
without ASC> or ASC-ECU <vehicles with ASC>

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.