Mitsubishi Colt Ralliart. Manual - part 321

DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-28

Step 2. M.U.T.-III other system diagnosis code
Check if a combination meter diagnosis code is set.

Q: Is the diagnosis code set?

YES : 

Diagnose the combination meter (Refer to 

GROUP 54A 

− Troubleshooting 

P.54A-31

).

NO : 

Go to Step 3.

Step 3. M.U.T.-III other system diagnosis code
Check whether the engine-ECU <M/T> or 
engine-CVT-ECU <CVT> sets meter and air-condi-
tioner-related time-out diagnosis code.

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Go to Step 5.

Step 4. Check whether the diagnosis code is 
reset
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Turn the ignition switch to the "LOCK" (OFF) 

position to "ON" position.

(3) On completion, check that the diagnosis code is 

not reset.

Q: Is the check result normal?

YES : . 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction 

P.00-13

).

NO : . 

Replace the combination meter 

(incorporating the meter and A/C-ECU).

Step 5. Check whether the diagnosis code is 
reset
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Turn the ignition switch to the "LOCK" (OFF) 

position to "ON" position.

(3) On completion, check that the diagnosis code is 

not reset.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction 

P.00-13

).

NO : 

Replace the ETACS-ECU.

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Index

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TOC

DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-29

Diagnosis code No.U1128: Meter and A/C-ECU failure information (related to meter)

CAUTION

• If diagnosis code No.U1128 is set in the 

ETACS-ECU, diagnose the CAN bus lines.

• Whenever the ECU is replaced, ensure that 

the input and output signal circuits are nor-
mal.

TROUBLE JUDGMENT

The ETACS-ECU receives combination 
meter-related signal from the combination meter via 
the CAN bus lines. If a fail-safe related data is con-
tained in the signal from the combination meter, diag-
nosis code No.U1128 will be stored.

COMMENT ON TROUBLE SYMPTOM

Current trouble

• Connector(s) or wiring harness in the CAN bus 

lines, the engine-ECU <M/T> or 
engine-CVT-ECU <CVT>, the combination meter 
or the ETACS-ECU may be defective.

Past trouble

• If diagnosis code No.U1128 is stored as a past 

trouble, carry out diagnosis with particular 
emphasis on wiring and connector(s) in the CAN 
bus line between the combination meter and the 
ETACS-ECU, and the power supply system to the 
combination meter. For diagnosis procedures, 
refer to "How to treat past trouble" (refer to 
GROUP 00, How to Use Troubleshooting/Inspec-
tion Service Points 

− How to Treat Past Trouble 

P.00-13

).

NOTE: For a past trouble, you can not find it by the 

M.U.T.-III CAN bus diagnostics even if there is 
any failure in CAN bus lines. In this case, refer to 
GROUP 00, How to Use Troubleshooting/Inspec-
tion Service Points 

−

 How to Cope with Intermit-

tent Malfunctions 

P.00-13

 and check the CAN 

bus lines. You can narrow down the possible 
cause of the trouble by referring to the diagnosis 
code, which is set regarding the CAN communi-
cation-linked ECUs (Refer to GROUP 54D 

−

 CAN 

Bus Line Diagnosis Flow 

P.54D-7

).

PROBABLE CAUSES

• Malfunction of the engine-ECU <M/T>

• Malfunction of the engine-CVT-ECU <CVT>

• Defective combination meter

• 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 
54D 

− Diagnosis 

P.54D-13

).

Step 2. M.U.T.-III other system diagnosis code
Check whether the engine-ECU <M/T> or 
engine-CVT-ECU <CVT> sets a diagnosis code.

Q: Is the diagnosis code set?

YES : 

Diagnose the engine or the CVT (Refer to 

GROUP 13A 

− Troubleshooting 

P.13A-20

 

<4A9>, GROUP 13B 

− Troubleshooting 

P.13B-18

 <4G1>, or GROUP 23A 

− 

Troubleshooting 

P.23A-14

 <CVT>).

NO : 

Go to Step 3.

Step 3. M.U.T.-III other system diagnosis code
Check whether the combination meter-related diag-
nosis code is set.

Q: Is the diagnosis code set?

YES : 

Diagnose the combination meter (Refer to 

GROUP 54A 

− Troubleshooting 

P.54A-31

).

NO : 

Go to Step 4.

Step 4. Check whether the diagnosis code is 
reset
Check again if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Turn the ignition switch to the "LOCK" (OFF) 

position to "ON" position.

(3) On completion, check that the diagnosis code is 

not reset.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction 

P.00-13

).

NO : 

Replace the ETACS-ECU.

Main

Index

Group

TOC

DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-30

Diagnosis code No.B1706: Blown fuse is detected in fuse No.31 (hazard fuse).

CAUTION

• If diagnosis code No.B1706 is set in the 

ETACS-ECU, diagnose the CAN bus lines.

• Whenever the ECU is replaced, ensure that 

the input and output signal circuits are nor-
mal.

TROUBLE JUDGMENT

When junction block fuse No.31 is blown, diagnosis 
diagnosis code No.B1706 is set. However, if the sys-
tem returns to normal condition, diagnosis code 
No.B1706 will be erased automatically.

COMMENT ON TROUBLE SYMPTOM

Junction block fuse No.31 or the ETACS-ECU may 
be defective.

PROBABLE CAUSES

• Malfunction of the Junction block fuse No. 31

• Damaged harness wires and connectors

• 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 
54D 

− Diagnosis 

P.54D-13

).

Step 2. Check the Junction block fuse No.31

Q: Is the fuse in good condition?

YES : 

Go to Step 3.

NO : 

Replace the Junction block fuse No.31, and 
then go to Step 6.

Step 3. Connector check: B-134 ETACS-ECU 
connector

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Repair the defective connector.

Step 4. Voltage measurement at the B-134 
ETACS-ECU connector

(1) Disconnect the connector, and measure at the 

wiring harness side.

(2) Voltage between B-134 ETACS-ECU connector 

terminal No. 5 and body earth

OK: System voltage

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 5.

AC313826

Connector: B-134

AG

Junction block side

Junction block (Rear view)

AC313826

Connector: B-134

AG

Junction block side

Junction block (Rear view)

AC310507 FG

Connector B-134
(Junction block side)

Main

Index

Group

TOC

DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-31

Step 5. Check the wiring harness between 
B-134ETACS-ECU connector terminal No. 1 to 
fusible link (1).

Check the power supply line for open circuit.
NOTE: 

Prior to the wiring harness inspection, check junction 
block connector B-108 and repair if necessary.

Q: Is the check result normal?

YES : . 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00 

− How to 

use Troubleshooting/inspection Service 
Points 

− How to Cope with Intermittent 

Malfunction 

P.00-13

).

NO : . 

Repair the wiring harness.

Step 6. Check whether the diagnosis code is 
reset.
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Turn the ignition switch to the "LOCK" (OFF) 

position to "ON" position.

(3) Check if the diagnosis code is set.

Q: Is the check result satisfactory?

YES : 

If a trouble is solved, it is determined that 

there is an intermittent malfunction such as 
poor engaged connector(s) or open circuit 
(Refer to GROUP 00 

− How to use 

Troubleshooting/inspection Service Points 

− 

How to Cope with Intermittent Malfunction 

P.00-13

).

NO : 

Replace the ETACS-ECU.

AC313826

Connector: B-134

AG

Junction block side

Junction block (Rear view)

AC313824 AG

Connector: B-108

Harness side

Junction block (Front view)

B-108 (B)

Main

Index

Group

TOC