Mitsubishi Colt Ralliart. Manual - part 633

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-77

STEP 3. Battery terminal voltage measurement
(1) Start the engine.
(2) Measure the voltage between the positive and 

negative battery terminals.

OK: 10 V or more

Q: Is the check result normal?

YES : 

Go to Step 4.

NO : 

Diagnose the charging system. (Refer to 
GROUP 16 

− On-vehicle Service 

P.16-6

.)

STEP 4. Measure the voltage at C-45 G and yaw 
rate sensor connector.

(1) Disconnect C-45 G and yaw rate sensor 

connector, and measure at the harness side.

(2) Measure the voltage between the terminal No. 1 

and the body earth.

OK: 9 V or more

Q: Is the check result normal?

YES : . 

Go to Step 7.

NO : . 

Go to Step 5.

STEP 5. Connector check: C-45 G and yaw rate 
sensor connector, B-110 junction block 
connector

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Repair the damaged connector.

AC601093

Connector: C-45

AC

C-45(Black)

Harness side

AC601339

Connector: C-45

AD

Harness side

AC601093

Connector: C-45

AC

C-45(Black)

Harness side

J/B

i ‡ û

j

AC601106

J/B

(Front view)

AC601106

Connector: B-110

AB

Harness side

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Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-78

STEP 6. Check the harness wire between C-45 G 
and yaw rate sensor connector and B-110 
junction block connector.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair the wiring harness.

STEP 7. Measure the resistance at C-45 G and 
yaw rate sensor connector.

(1) Disconnect C-45 G and yaw rate sensor 

connector, and measure at the harness side.

(2) Measure the resistance between the terminal No. 

4 and the body earth.

OK: Continuity exists (2 

Ω or less)

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Repair the wiring harness.

STEP 8. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON

Q: Is the diagnosis code No. C1863 set?

YES : 

Replace the G and yaw rate sensor.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Cope with Intermittent 

Malfunction 

P.00-13

.)

AC601093

Connector: C-45

AC

C-45(Black)

Harness side

J/B

i ‡ û

j

AC601106

J/B

(Front view)

AC601106

Connector: B-110

AB

Harness side

AC601093

Connector: C-45

AC

C-45(Black)

Harness side

AC601339

Connector: C-45

AE

Harness side

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-79

Code No. U1073: Bus-off

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.

DIAGNOSIS CODE SET CONDITIONS

When ASC-ECU has ceased the CAN communica-
tion (bus-off), the diagnosis code No. U1073 is 
stored. The communication is resumed when the 
ignition switch is tuned to the "LOCK" (OFF) position 
and then to ON position again.  

Probable causes

• Damaged wiring harness and connectors

DIAGNOSTIC PROCEDURE

M.U.T.-III CAN bus diagnosis
Use the M.U.T.-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES : 

Intermittent malfunction (Refer to GROUP 

00 

− How to Cope with Intermittent 

Malfunction 

P.00-13

.)

NO : 

Repair the CAN bus lines. (Refer to GROUP 
54D 

− Troubleshooting 

P.54D-13

.)

Code No. U1100: Engine-related CAN time-out error

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.

DIAGNOSIS CODE SET CONDITIONS

ASC-ECU receives the engine control sys-
tem-related signals from the engine ECU via the 
CAN bus lines. When these signals cannot be 
received, the ECU stores the diagnosis code No. 
U1100.

COMMENTS ON TROUBLE SYMPTOM

Current trouble

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

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

Past trouble

• If diagnosis code No. U1100 is stored as a past 

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

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 Troubleshoot-

ing/Inspection Service Points 

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 
communication-linked ECUs (Refer to GROUP 
54D 

−

 CAN Bus Line Diagnostic Flow 

P.54D-7

).

Probable causes

• Engine ECU malfunction

• ASC-ECU malfunction

• Damaged wiring harness and connectors

DIAGNOSTIC 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 3.

NO : 

Repair the CAN bus lines. (Refer to GROUP 
54D 

− Troubleshooting 

P.54D-13

.) On 

completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting 
CAN bus lines

Q: Is the diagnosis code No. U1100 set?

YES : 

Go to Step 3.

NO : 

This diagnosis is complete.

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-80

STEP 3. M.U.T.-III diagnosis code for other 
systems
Use M.U.T.-III to check that other diagnosis code is 
set in the ECU corresponding to the relevant diagno-
sis code.

Q: Is other diagnosis code set?

YES : 

Troubleshoot for the relevant diagnosis 

code.

NO : 

Replace the engine ECU. Then go to Step 
4.

STEP 4. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON

Q: Is the diagnosis code No. U1100 set?

YES : 

Replace the ASC-ECU.

NO : 

This diagnosis is complete.

Code No. U1104: Steering wheel sensor CAN time-out error

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.

DIAGNOSIS CODE SET CONDITIONS

ASC-ECU receives the steering angle-related sig-
nals from the steering wheel sensor via the CAN bus 
lines. When these signals cannot be received, the 
diagnosis code No. U1104 is stored.

COMMENTS ON TROUBLE SYMPTOM

Current trouble

• The connector(s) or wiring harness in the CAN 

bus line between ASC-ECU and the steering 
wheel sensor may be damaged, or the steering 
wheel sensor power supply circuit or ASC-ECU 
may be faulty.

Past trouble

• If diagnosis code No. U1104 is stored as a past 

trouble, carry out diagnosis with particular 
emphasis on connector(s) and wiring harness in 
the CAN bus line between the ASC-ECU and the 
steering wheel sensor, and the steering wheel 
sensor power supply circuit. For diagnosis proce-
dures, refer to How to treat past trouble (refer to 
GROUP 00, How to Use Troubleshooting/Inspec-
tion Service Points 

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 Troubleshoot-

ing/Inspection Service Points 

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 
communication-linked ECUs. (Refer to GROUP 
54D 

−

 CAN Bus Line Diagnostic Flow 

P.54D-7

.)

Probable causes

• Steering wheel sensor malfunction

• ASC-ECU malfunction

• Damaged wiring harness and connectors

DIAGNOSTIC 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 3.

NO : 

Repair the CAN bus lines. (Refer to GROUP 
54D 

− Troubleshooting 

P.54D-13

.) On 

completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting 
CAN bus lines

Q: Is the diagnosis code No. U1104 set?

YES : 

Replace the steering wheel sensor.(Refer to 

P.35C-125

.) Then go to Step 3.

NO : 

This diagnosis is complete.

STEP 3. Diagnosis code recheck
Recheck if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition switch: LOCK (OFF) position
(3) Ignition switch: ON

Q: Is the diagnosis code No. U1104 set?

YES : 

Replace the ASC-ECU.

NO : 

Intermittent malfunction (Refer to GROUP 
00 

− How to Cope with Intermittent 

Malfunction 

P.00-13

.)

Main

Index

Group

TOC