Mitsubishi Lancer (4A9 engine). Manual - part 64

 

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Mitsubishi Lancer (4A9 engine). Manual - part 64

 

 

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-109

STEP 3. M.U.T.-III diagnosis code
Check that the engine ECU sets a diagnosis code.

Q: Is any diagnosis code set?

YES : 

Troubleshoot the engine ECU (Refer to 

GROUP 13A 

− Troubleshooting/Diagnosis 

function  <4A9>, GROUP 13B 

− 

Troubleshooting/Diagnosis function  <4B1>, 
GROUP 13F 

− Troubleshooting/Diagnosis 

function  <4J1> or GROUP 13C 

− 

Troubleshooting/Diagnosis function  
<4N1>), and then go to Step 5.

NO : 

Go to Step 4.

STEP 4. Check whether the diagnosis code is 
reset.

Q: Is diagnosis code No.C2203 set?

YES : 

Replace the hydraulic unit (integrated with 

ASC-ECU) (Refer to 

P.35C-185

), and then 

go to Step 5.

NO : 

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/How to Cope with 
Intermittent Malfunctions ).

STEP 5. Check whether the diagnosis code is 
reset.
Erase the diagnosis code.

Q: Is diagnosis code No.C2203 set?

YES : 

Return to Step 1.

NO : 

This diagnosis is complete.

Code No.C2206 Re-execution of variant coding

CAUTION

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

an incorrect diagnosis code may be set. Prior 
to this diagnosis, diagnose the CAN bus lines 
(Refer to GROUP 54C 

 CAN Bus Diagnostics 

Table ).

• If diagnosis code No.C2206 is set in ASC-

ECU, always diagnose the CAN bus line. If 
there is any fault in the CAN bus lines, an 
incorrect diagnosis code may be set. In this 
case, the set diagnosis code is not highly reli-
able.

• Before replacing the ECU, ensure that the 

communication circuit is normal.

• When diagnosis code No.C2206 is set in ASC-

ECU, the diagnosis code may also be set in 
ETACS-ECU. When the diagnosis code is set 
in ETACS-ECU, carry out the diagnosis of the 
diagnosis code for ETACS-ECU first.

• When the hydraulic unit (integrated with ASC-

ECU) is replaced, always carry out the calibra-
tion of the steering wheel sensor, the G and 
yaw rate sensor and brake fluid pressure sen-
sor (Refer to 

P.35C-182

P.35C-183

 an

P.35C-

184

).

OPERATION
ASC-ECU receives the vehicle information stored in 
the ETACS-ECU via CAN bus lines.

DIAGNOSIS CODE SET CONDITIONS
ASC-ECU communicates with ETACS-ECU via CAN 
bus lines. This diagnosis code is set if the vehicle 
information-related stored in ETACS-ECU varies 
from the one stored when the ignition switch was last 
turned on.

PROBABLE CAUSES

• ETACS-ECU or ASC-ECU which was equipped 

with other vehicle is used.

• Malfunction of ETACS-ECU

• ASC-ECU malfunction

• External noise interference

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnostics
Use 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 lines (Refer to GROUP 
54C 

− CAN Bus Diagnostics Table ). On 

completion, go to Step 6.

STEP 2. M.U.T.-III diagnosis code
Check that diagnosis code U1415 or U1417 is set in 
ASC-ECU.

Q: Is the diagnosis code set?

YES : 

Troubleshoot for the relevant diagnosis 

code (Refer to 

P.35C-16

).

NO : 

Go to Step 3.

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-110

STEP 3. M.U.T.-III Diagnosis code of other system
Use M.U.T.-III to check that the vehicles information-
related diagnosis code is set by the ETACS-ECU.

Q: Is the diagnosis code set?

YES : 

Troubleshoot the relevant diagnosis code, 

and then go to Step 4.

NO : 

Go to Step 6.

STEP 4. ETACS-ECU coding data check

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Go to Step 5.

STEP 5. ETACS-ECU variant coding
Perform the variant coding to the ETACS-ECU.

Q: Dose variant coding succeed?

YES : 

Go to Step 7.

NO : 

Replace the ETACS-ECU (Refer to GROUP 
54A 

− ETACS-ECU ), and then go to Step 7.

STEP 6. Check whether the diagnosis code is 
reset.
Erase the diagnosis code.

Q: Is diagnosis code No.C2206 set?

YES : 

Replace the hydraulic unit (integrated with 

ASC-ECU) (Refer to 

P.35C-185

). Then go 

to Step 7.

NO : 

This diagnosis is complete.

STEP 7. Check whether the diagnosis code is 
reset.
Erase the diagnosis code.

Q: Is diagnosis code No.C2206 set?

YES : 

Return to Step 1.

NO : 

This diagnosis is complete.

Code No. C123C Abnormality in G and yaw rate sensor output value (Abnormality in lateral G and yaw 
rate output value)

G and Yaw Rate Sensor Circuit

G AND YAW RATE SENSOR

ASC-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

ACB02567

AC612691

AO

Connector: A-58 <LHD>

A-58 (B)

AC701238 AF

Connector: A-58 <RHD>

A-58 (B)

AC801697AO

Connector: C-137 <LHD>

C-137 (B)

AC801699AK

Connector: C-137 <RHD>

C-137 (B)

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-111

CAUTION

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

an incorrect diagnosis code may be set. Prior 
to this diagnosis, diagnose the CAN bus lines 
(Refer to GROUP 54C 

 CAN Bus Diagnostics 

Table ).

• Whenever ECU is replaced, ensure that the 

CAN bus lines are normal.

• Do not drop or shock the G and yaw rate sen-

sor.

• When the G and yaw rate sensor is replaced, 

always carry out calibration to make ASC-
ECU learn the neutral point (Refer to 

P.35C-

182

).

• When the hydraulic unit (integrated with ASC-

ECU) is replaced, always carry out the calibra-
tion of the steering wheel sensor, the G and 
yaw rate sensor and brake fluid pressure sen-
sor (Refer to 

P.35C-182

P.35C-183

 an

P.35C-

184

).

OPERATION
ABS-ECU monitors if the output of G and yaw rate 
sensor is normal or not.

DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set if any malfunction below is 
found:

• The output value of lateral G and yaw rate is 

abnormal.

• When abnormality is detected by comparing the 

value output from the lateral G and yaw rate sen-
sor with the one from the steering wheel sensor 
and wheel speed sensor

PROBABLE CAUSES

• Improper installation of the G and yaw rate sen-

sor

• G and yaw rate sensor malfunction

• Steering wheel sensor malfunction

• Improperly installed steering wheel sensor

• Malfunction of wheel speed sensor

• ASC-ECU malfunction

• External noise interference

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III CAN bus diagnosis
Use 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 lines (Refer to GROUP 
54C 

− CAN Bus Diagnostics Table ). On 

completion, go to Step 2.

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-112

STEP 2. M.U.T.-III diagnosis code
Check that the diagnosis code U0125 is set in ASC-
ECU.

Q: Is the diagnosis code No.U0125 set?

YES : 

Troubleshoot for the diagnosis code (Refer 

to 

P.35C-133

). Then go to Step 3.

NO : 

Go to Step 3.

STEP 3. Diagnosis code recheck after resetting 
CAN bus lines

Q: Is the diagnosis code No.C123C set?

YES : 

Go to Step 4.

NO : 

This diagnosis is complete.

STEP 4. Check the wheel speed sensor-related or 
steering wheel sensor-related diagnosis code.
Use M.U.T.-III to check whether the wheel speed 
sensor-related or steering wheel sensor-related diag-
nosis code is set or not.

Q: Is the diagnosis code set?

YES : 

Troubleshoot for the relevant diagnosis 

code (Refer to 

P.35C-16

).

NO : 

Go to Step 5.

STEP 5. G and yaw rate sensor installation check
Check that the G and yaw rate sensor is installed 
correctly.

Q: Is the check result normal?

YES : 

After checking the G and yaw rate sensor, 

carry out calibration of the G and yaw rate 
sensor to make ASC-ECU relearn the 
neutral point. (Refer to 

P.35C-182

.) Then go 

to Step 6.

NO : 

Reinstall the G and yaw rate sensor 
correctly (Refer to 

P.35C-189

), and then go 

to Step 12.

STEP 6. M.U.T.-III data list
Check the following data list (Refer to 

P.35C-172

).

• Item 08: Lateral G-sensor

• Item 12: Yaw rate sensor

Q: Is the check result normal?

YES : 

Go to Step 9.

NO : 

Go to Step 7.

STEP 7. Connector check: A-58 ASC-ECU 
connector, C-137 G and yaw rate sensor

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Repair the connector, and then go to Step 
13.

STEP 8. Check the harness wire between C-137 G 
and yaw rate sensor connector terminal No. 2, 3 
and A-58 ASC-ECU connector No. 18, 19.

• Check the communication lines for open circuit 

and short circuit.

Q: Is the check result normal?

YES : 

Replace the G and yaw rate sensor.(Refer 

to 

P.35C-189

.) Then go to Step 12.

NO : 

Repair the wiring harness, and then go to 
Step 13.

STEP 9. Steering wheel sensor installation check
Check that the steering wheel sensor is installed cor-
rectly.

Q: Is the check result normal?

YES : 

Go to Step 10.

NO : 

Reinstall the steering wheel sensor correctly 
(Refer to 

P.35C-190

), and then go to Step 

10.

STEP 10. Wheel alignment check
Refer to .

Q: Is the check result normal?

YES : 

After checking the wheel alignment, carry 

out calibration of steering wheel sensor to 
make ASC-ECU relearn the neutral point. 
(Refer to 

P.35C-183

). Then go to Step 11.

NO : 

After adjusting the wheel alignment, carry 
out calibration of steering wheel sensor to 
make ASC-ECU relearn the neutral point 
(Refer to 

P.35C-183

). Then go to Step 11.

STEP 11. M.U.T.-III data list
Check the following data list (Refer to 

P.35C-172

).

• Item 11: Steering angle sensor

Q: Is the check result normal?

YES : 

Go to Step 12.

NO : 

Replace the steering wheel sensor (Refer to 

P.35C-190

), and then go to Step 12.

STEP 12. Check whether the diagnosis code is 
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 20 km/h or higher.

Q: Is the diagnosis code No.C123C set?

 

 

 

 

 

 

 

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