Mitsubishi Outlander GS45X. Manual — part 439

DIAGNOSIS

TSB Revision

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-183

DTC C121A: Abnormality in steering wheel sensor initialization

CAUTION

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

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

− CAN Bus Line Diagnostic Flow

P.54C-10

).

• Whenever ECU is replaced, ensure that the CAN bus

lines are normal.

• When the steering wheel sensor is replaced, always

carry out calibration to make ASC-ECU learn the neu-
tral point (Refer to

P.35C-283

).

• When the hydraulic unit (integrated with ASC-ECU) is

replaced, always carry out the calibration of the steer-
ing wheel sensor, the G and yaw rate sensor and brake
fluid pressure sensor (Refer to

P.35C-282

,

P.35C-283

and

P.35C-284

).

.

OPERATION

Steering wheel sensor stores the neutral position learned by
the scan tool. When the neutral position has not been stored in
the steering wheel sensor yet, the steering wheel sensor out-
puts the signal indicating that it does not have neutral position.

.

DTC SET CONDITIONS

This diagnostic trouble code is set when ASC-ECU detects that
the steering wheel sensor has not learned the neutral position
yet.

.

PROBABLE CAUSES

• Steering wheel sensor malfunction

• ASC-ECU malfunction

• Neutral position of steering wheel sensor not learned

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus
lines.
Use scan tool 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 54C

−

CAN Bus Diagnostics Table

P.54C-17

). On

completion, go to Step 2.

DIAGNOSIS

TSB Revision

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-184

STEP 2. DTC recheck after resetting CAN bus lines
Q: Is DTC C121A set?

YES : Go to Step 3.
NO : The procedure is complete.

STEP 3. Steering wheel sensor calibration
Perform calibration of steering wheel sensor (Refer to

P.35C-283

).

Q: Has the calibration succeeded?

YES : Go to Step 4.
NO : After the steering wheel sensor is replaced, perform

the steering wheel sensor calibration to make
ASC-ECU learn the neutral point again (Refer to

P.35C-283

). Then go to Step 4.

STEP 4. Check whether the DTC is reset.
Erase the DTC.
Q: Is DTC C121A set?

YES : Replace the hydraulic unit (integrated with ASC-ECU)

(Refer to

P.35C-287

), and then go to Step 5.

NO : The procedure is complete.

STEP 5. Check whether the DTC is reset.
Erase the DTC.
Q: Is DTC C121A set?

YES : Return to Step 1.
NO : The procedure is complete.

DTC C2205: Internal malfunction of steering wheel sensor

CAUTION

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

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

− CAN Bus Line Diagnostic Flow

P.54C-10

).

• Whenever ECU is replaced, ensure that the CAN bus

lines are normal.

• When the steering wheel sensor is replaced, always

carry out calibration to make ASC-ECU learn the neu-
tral point (Refer to

P.35C-283

).

• When the hydraulic unit (integrated with ASC-ECU) is

replaced, always carry out the calibration of the steer-
ing wheel sensor, the G and yaw rate sensor and brake
fluid pressure sensor (Refer to

P.35C-282

,

P.35C-283

and

P.35C-284

).

.

CIRCUIT OPERATION

• Steering wheel sensor sends its status signal to ASC-ECU.

DIAGNOSIS

TSB Revision

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-185

.

DTC SET CONDITIONS

This diagnostic trouble code is set when ASC-ECU detects that
the steering wheel sensor has malfunction.

.

PROBABLE CAUSES

• Steering wheel sensor malfunction

• ASC-ECU malfunction

• External noise interference

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus
lines.
Use scan tool 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

P.54C-17

). On

completion, go to Step 4.

STEP 2. Check whether the DTC is reset.
Erase the DTC.
Q: Is DTC C2205 set?

YES : Replace the steering wheel sensor (Refer to

P.35C-291

), and then go to Step 3.

NO : The procedure is complete.

STEP 3. Check whether the DTC is reset.
Erase the DTC.
Q: Is DTC C2205 set?

YES : Replace the hydraulic unit (integrated with ASC-ECU)

(Refer to

P.35C-287

), and then go to Step 4.

NO : The procedure is complete.

STEP 4. Check whether the DTC is reset.
Erase the DTC.
Q: Is DTC C2205 set?

YES : Return to Step 1.
NO : The procedure is complete.

DIAGNOSIS

TSB Revision

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-186

DTC C2002: Valve calibration not completed

.

CAUTION

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

rect DTC may be set. Prior to this diagnosis, diagnose
the CAN bus lines (Refer to GROUP 54C

− CAN Bus

Line Diagnostic Flow

P.54C-10

).

• Whenever ECU is replaced, ensure that the CAN bus

lines are normal.

• When the hydraulic unit (integrated with ASC-ECU) is

replaced, always carry out the calibration of the steer-
ing wheel sensor, the G and yaw rate sensor and brake
fluid pressure sensor (Refer to

P.35C-282

,

P.35C-283

and

P.35C-284

).

.

OPERATION

Perform the master cylinder pressure sensor calibration to
store the calibrated value in the ASC-ECU. At the same time,
the calibrated value of cut valve and inlet valve are stored.

.

DTC SET CONDITIONS

This DTC is set when the calibrated values for cut valve and
inlet valve stored in ASC-ECU are not within the predetermined
range.

.

PROBABLE CAUSES

• ASC-ECU malfunction

• Noise interference

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (M.U.T.-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: M.U.T.-III USB Cable

• MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus
lines.
Use scan tool 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 54C

−

CAN Bus Diagnostics Table

P.54C-17

). On

completion, go to Step 2.

STEP 2. DTC recheck after resetting CAN bus lines
Q: Is DTC C2002 set?

YES : Replace the hydraulic unit (integrated with ASC-ECU)

(Refer to

P.35C-287

). Then go to Step 3.

NO : The procedure is complete.