Mitsubishi Lancer (4A9 engine). Manual - part 176

MITSUBISHI MULTI COMMUNICATION SYSTEM (MMCS)

CHASSIS ELECTRICAL

54A-366

Code No.B2477: Chassis No. not programmed

CAUTION

• If the diagnosis code No. B2477 is set, be sure 

to diagnose the CAN bus line.

• When replacing the CAN box unit, always 

check that the communication circuit is nor-
mal. (Check that the voltage is 10 V or more.)

TROUBLE JUDGEMENT
With the ignition switch at the ON position, if the 
Chassis No. is not written to the CAN box unit, diag-
nosis code B2477 is stored.

PROBABLE CAUSES

• Malfunction of the CAN bus line.

• Malfunction of the ETACS-ECU.

• Malfunction of the CAN box unit.

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. M.U.T.-III other system diagnosis code
Check if the diagnosis code relating to the coding 
error is set to the ETACS-ECU.

Q: Is the diagnosis code set?

YES : 

Diagnose the ETACS-ECU (Refer to 

GROUP 54A 

− ETACS-ECU − 

Troubleshooting ).

NO : 

Go to Step 3.

STEP 3. Recheck for diagnosis code.
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the CAN box unit.

NO : 

The trouble can be an intermittent 
malfunction (Refer to GROUP 00, How to 
use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction ).

Code No.U0019 Bus off (CAN-B)

CAUTION

• If there is any problem in the CAN bus lines, 

an incorrect diagnosis code may be set. Prior 
to this diagnosis, always diagnose the CAN 
bus lines.

• Before replacing the CAN box unit, be sure to 

check that the power supply circuit, earth cir-
cuit, and communication circuit are normal. 
(Check that the voltage is 10 V or more.)

TROUBLE JUDGEMENT
When the CAN box unit is returned from the bus off 
state, or when the bus error is indicated to the CAN 
box unit state, the diagnosis code U0019 (CAN-B) is 
set.

COMMENTS ON TROUBLE SYMPTOM
The CAN box unit, power supply for the CAN box 
unit, earth circuit, or CAN bus line may have a prob-
lem.

PROBABLE CAUSES

• Malfunctions of CAN box unit

• Malfunction of CAN bus line wiring harness and 

connector

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. Check whether the M.U.T.-III can 
communicate with the CAN box unit.

Q: Is the check result normal?

YES : 

 Erase the diagnosis code. This diagnosis is 

complete.

NO : 

Check the power supply circuit of the CAN 
box unit, and repair if necessary.

MITSUBISHI MULTI COMMUNICATION SYSTEM (MMCS)

CHASSIS ELECTRICAL

54A-367

Code No.U0141 ETACS CAN timeout

CAUTION

• If the diagnosis code No. U0141 is set, be sure 

to diagnose the CAN bus line.

• When replacing the CAN box unit, always 

check that the communication circuit is nor-
mal. (Check that the voltage is 10 V or more.)

DIAGNOSTIC FUNCTION
If the signal from ETACS-ECU cannot be received, 
the CAN box unit sets the diagnosis code No. 
U0141.

JUDGEMENT CRITERIA
With the statuses that the ignition switch is at ON 
position, system voltage is 10 

− 16 V (data from 

ETACS-ECU), and there is no malfunction to the 
power supply fuse (IOD fuse), or odometer value is 
80.5 km or more, if the communication with ETACS-
ECU cannot be established for 2,500 ms or more, 
the CAN box unit determines that a problem has 
occurred.

PROBABLE CAUSES

• Malfunction of CAN bus line

• Malfunction of CAN box unit

• Malfunction of the ETACS-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. M.U.T.-III other system diagnosis code
Check again if the diagnosis code is set to the 
ETACS-ECU.

Q: Is the diagnosis code set?

YES : 

Diagnose the ETACS-ECU (Refer to 

GROUP 54A 

− ETACS-ECU − 

Troubleshooting ).

NO : 

Go to Step 3.

STEP 3. Check the M.U.T.-III Diagnosis code for 
other systems
Check if the diagnosis code No. U0141 is set to com-
bination meter.

Q: Is the diagnosis code set?

YES : 

Go to Step 4.

NO : 

Go to Step 5.

STEP 4. Diagnosis code recheck
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from the LOCK (OFF) 

position to the ON position.

(3) Check if the diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the ETACS-ECU.

NO : 

A poor connection, open circuit or other 
intermittent malfunction in the CAN bus line 
between the CAN box unit and the ETACS-
ECU. (Refer to GROUP 00 

− How to Use 

Troubleshooting/Inspection Service Points - 
How to Cope with Intermittent Malfunction .)

STEP 5. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the CAN box unit.

NO : 

A poor connection, open circuit or other 
intermittent malfunction in the CAN bus line 
between the CAN box unit and the ETACS-
ECU. (Refer to GROUP 00 

− How to Use 

Troubleshooting/Inspection Service Points - 
How to Cope with Intermittent Malfunction .)

MITSUBISHI MULTI COMMUNICATION SYSTEM (MMCS)

CHASSIS ELECTRICAL

54A-368

Code No.U0151 SRS-ABG CAN timeout

CAUTION

• If the diagnosis code No. U0151 is set, be sure 

to diagnose the CAN bus line.

• When replacing the CAN box unit, always 

check that the communication circuit is nor-
mal. (Check that the voltage is 10 V or more.)

DIAGNOSTIC FUNCTION
If the signal from SRS-ECU cannot be received, the 
CAN box unit sets the diagnosis code No. U0151.

JUDGEMENT CRITERIA
With the statuses that the ignition switch is at ON 
position, system voltage is 10

−16 V (data from 

ETACS-ECU), and there is no malfunction to the 
power supply fuse (IOD fuse), or odometer value is 
80.5 km or more, if the communication with SRS-
ECU cannot be established for 2,500 ms or more, 
the CAN box unit determines that a problem has 
occurred.

PROBABLE CAUSES

• Malfunction of CAN bus line

• Malfunction of the SRS-ECU

• Malfunction of CAN box unit

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. M.U.T.-III other system diagnosis code
Check again if the diagnosis code is set to the SRS-
ECU.

Q: Is the diagnosis code set?

YES : 

Troubleshoot the SRS-ECU (Refer to 

GROUP 52B 

− Troubleshooting ).

NO : 

Go to Step 3.

STEP 3. Check the M.U.T.-III Diagnosis code for 
other systems
Check if the diagnosis code No. U0151 is set to com-
bination meter.

Q: Is the diagnosis code set?

YES : 

Go to Step 4.

NO : 

Go to Step 5.

STEP 4. Diagnosis code recheck
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from the LOCK (OFF) 

position to the ON position.

(3) Check if the diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the SRS-ECU.

NO : 

A poor connection, open circuit or other 
intermittent malfunction in the CAN bus line 
between the CAN box unit and the SRS-
ECU. (Refer to GROUP 00 

− How to Use 

Troubleshooting/Inspection Service Points - 
How to Cope with Intermittent Malfunction .)

STEP 5. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the CAN box unit.

NO : 

A poor connection, open circuit or other 
intermittent malfunction in the CAN bus line 
between the CAN box unit and the SRS-
ECU. (Refer to GROUP 00 

− How to Use 

Troubleshooting/Inspection Service Points - 
How to Cope with Intermittent Malfunction .)

MITSUBISHI MULTI COMMUNICATION SYSTEM (MMCS)

CHASSIS ELECTRICAL

54A-369

Code No.U0155 Meter CAN timeout

CAUTION

• If the diagnosis code No. U0155 is set, be sure 

to diagnose the CAN bus line.

• When replacing the CAN box unit, always 

check that the communication circuit is nor-
mal. (Check that the voltage is 10 V or more.)

DIAGNOSTIC FUNCTION
If the signal from combination meter cannot be 
received, the CAN box unit sets the diagnosis code 
No. U0155.

JUDGEMENT CRITERIA
With the statuses that the ignition switch is at ON 
position, system voltage is 10

−16 V (data from 

ETACS-ECU), and there is no malfunction to the 
power supply fuse (IOD fuse), or odometer value is 
80.5 km or more, if the communication with combina-
tion meter cannot be established for 2,500 ms or 
more, the CAN box unit determines that a problem 
has occurred.

PROBABLE CAUSES

• Malfunction of CAN bus line

• Malfunction of the combination meter

• Malfunction of CAN box unit

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Go to Step 2.

NO : 

Repair the CAN bus line (Refer to GROUP 
54C 

− Troubleshooting ).

STEP 2. M.U.T.-III other system diagnosis code
Check again if the diagnosis code is set to the combi-
nation meter.

Q: Is the diagnosis code set?

YES : 

Troubleshoot the combination meter (Refer 

to ).

NO : 

Go to Step 3.

STEP 3. Check the M.U.T.-III Diagnosis code for 
other systems
Check if the diagnosis code No. U0155 is set to 
ETACS-ECU.

Q: Is the diagnosis code set?

YES : 

Go to Step 4.

NO : 

Go to Step 5.

STEP 4. Diagnosis code recheck
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from the LOCK (OFF) 

position to the ON position.

(3) Check if the diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the combination meter.

NO : 

A poor connection, open circuit or other 
intermittent malfunction in the CAN bus line 
between the CAN box unit and the 
combination meter. (Refer to GROUP 00 

− 

How to Use Troubleshooting/Inspection 
Service Points - How to Cope with 
Intermittent Malfunction .)

STEP 5. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set to the CAN 
box unit.
(1) Erase the diagnosis code.
(2) Turn the ignition switch from "LOCK" (OFF) 

position to "ON" position.

(3) Check if diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Replace the CAN box unit.

NO : 

A poor connection, open circuit or other 
intermittent malfunction in the CAN bus line 
between the CAN box unit and the 
combination meter. (Refer to GROUP 00 

− 

How to Use Troubleshooting/Inspection 
Service Points - How to Cope with 
Intermittent Malfunction .)