Mitsubishi Colt Ralliart. Manual - part 320

DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-24

Diagnosis code No.U1073: Bus off

CAUTION

If diagnosis code No.U1703 is set in the 
ETACS-ECU, diagnose the CAN bus lines.

CAUTION

Whenever the ECU is replaced, ensure that the 
input and output signal circuits are normal.

TROUBLE JUDGMENT

Diagnosis code No.U1703 will be stored when the 
ETACS-ECU ceases CAN communication (bus off) 
and then resumes the communication by turning the 
ignition switch to the "LOCK" (OFF) position.

COMMENTS ON TROUBLE SYMPTOM

The wiring harness wire or connectors may have 
loose, corroded, or damage terminals, or terminals 
pushed back in the connector, or the SWS communi-
cation lines may be defective.

POSSIBLE CAUSES

Damaged harness wires and connectors

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

). On completion, 

go to Step 3.

Step 2. Check whether the diagnosis code is 
reset.
Check again if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition: LOCK (OFF) position to ON
(3) On completion, check that the diagnosis code is 

not reset.

Q: Is the check result normal?

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, and then go to 
Step 3.

Step 3. Check whether the diagnosis code is 
reset.
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position to ON
(3) Check if the diagnosis code is set.

Q: Is diagnoscode No.U1073 set?

YES : 

Return to Step 1.

NO : 

The procedure is complete.

Diagnosis code No.U1100: Engine-ECU <M/T> or Engine-CVT-ECU <CVT> time-out (related to engine)

 

Diagnosis code No.U1101: Engine-CVT-ECU time-out (related to CVT) <CVT>

CAUTION

• If diagnosis code No.U1100 or No.U1101 are 

set in the ETACS, diagnose the CAN main bus 
line.

• Whenever the ECU is replaced, ensure that 

the communication circuit is normal.

TROUBLE JUDGMENT

Diagnosis Code No.U1100

• The ETACS-ECU receives engine and transmis-

sion control signals from the engine-ECU <M/T> 
or engine-CVT-ECU <CVT> through the CAN bus 
lines. If the ECU can not receive the engine con-
trol system-related signal at all, diagnosis code 
No.U1100 will be set.

Diagnosis Code No.U1101

• The ETACS-ECU receives engine and transmis-

sion control signals from the engine-CVT-ECU 
through the CAN bus lines. If the ECU can not 
receive the transmission control system-related 
signal at all, diagnosis code No.U1101 will be set.

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DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-25

COMMENTS ON TROUBLE SYMPTOM

Current trouble

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

lines between the ETACS-ECU and the 
engine-ECU <M/T> or engine-CVT-ECU <CVT>, 
the power supply circuits to these ECUs, or the 
ETACS-ECU itself may be defective.

Past trouble

• If diagnosis code No.U1100 and No.U1101 are 

set as past trouble, carry out diagnosis with par-
ticular emphasis on wiring and connector(s) in 
the CAN bus lines between the ETACS-ECU and 
the engine-ECU <M/T> or engine-CVT-ECU 
<CVT>, or power supply to the engine-ECU 
<M/T> or engine-CVT-ECU <CVT>. For diagno-
sis procedures, refer to "How to treat past trou-
ble" (refer to GROUP 00, How to Use 
Troubleshooting/Inspection 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>

• Malfunction of the ETACS-ECU

• Malfunction of the CAN bus

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

). Repair the 

CAN bus line.

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 check result normal?

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 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 engine-ECU <M/T> or 
engine-CVT-ECU <CVT>.

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 "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-26

Diagnosis code No.U1102: ABS-ECU or ASC-ECU time-out

CAUTION

• If diagnosis code No.U1102 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 ABS or ASC sys-
tem-related signals from the ABS-ECU or ASC-ECU. 
If meter-related signal can not be received at all, 
diagnosis code No.U1102 will be set.

COMMENT ON TROUBLE SYMPTOM

Current trouble

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

lines between the ABS-ECU or ASC-ECU and 
the ETACS-ECU, the power supply system to the 
ABS-ECU or ASC-ECU, the ABS-ECU or 
ASC-ECU itself, or the ETACS-ECU may be 
defective.

Past trouble

• If diagnosis code No.U1102 are stored as a past 

trouble, carry out diagnosis with particular 
emphasis on wiring and connector(s) in the CAN 
bus line between the ABS-ECU or ASC-ECU and 
the ETACS-ECU, and the power supply system to 
the ABS-ECU or ASC-ECU. For diagnosis proce-
dures, 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 ABS-ECU

• Malfunction of the ASC-ECU

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

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

). On completion, 

go to Step 5.

Step 2. M.U.T.-III other system diagnosis code
Check if a ABS-ECU or ASC-ECU diagnosis code is 
set.

Q: Is the diagnosis code set?

YES : 

Diagnose the ABS or ASC (Refer to 

GROUP 35B 

− Troubleshooting 

P.35B-7

 

<ABS> or GROUP 35C 

− Troubleshooting 

P.35C-6

 <ASC>).

NO : 

Go to Step 3.

Step 3. M.U.T.-III other system diagnosis code
Check whether the combination meter sets ABS or 
ASC-related time-out diagnosis code.

Q: Is the diagnosis code set?

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 ABS-ECU or ASC-ECU.

Main

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TOC

DIAGNOSIS TROUBLE CODE PROCEDURES

SMART WIRING SYSTEM (SWS) NOT USING SWS MONITOR

54B-27

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.

Diagnosis code No.U1110: Meter and A/C-ECU time-out (related to A/C)

 

Diagnosis code No.U1108: Meter and A/C-ECU time-out (related to meter)

CAUTION

• If diagnosis code No.U1110 or No.U1108 are 

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

Diagnosis Code No.U1110

• The ETACS-ECU receives air conditioner system 

and meter-related signals from the combination 
meter (incorporating the meter and A/C-ECU). If 
air conditioner control system-related signal can 
not be received at all, diagnosis code No.U1110 
will be set.

Diagnosis Code No.U1108

• The ETACS-ECU receives air conditioner system 

and meter-related signals from the combination 
meter (incorporating the meter and A/C-ECU). If 
meter-related signal can not be received at all, 
diagnosis code No.U1108 will be set.

COMMENT ON TROUBLE SYMPTOM

Current trouble

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

lines between the A/C-ECU and the 
ETACS-ECU, the power supply system to the 
combination meter, the combination meter itself, 
or the ETACS-ECU may be defective.

Past trouble

• If diagnosis code No.U1110 or No.U1108 are 

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 sys-

tem to the combination meter. For diagnosis pro-
cedures, refer to "How to treat past trouble" (refer 
to GROUP 00, How to Use Troubleshoot-
ing/Inspection 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 combination meter (incorporat-

ing the meter and A/C-ECU)

• Malfunction of the ETACS-ECU

• Damaged harness wires and connectors

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

). On completion, 

go to Step 5.

Main

Index

Group

TOC