Mitsubishi Outlander GS45X. Manual - part 402

DIAGNOSIS

TSB Revision

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-35

STEP 5. Resistance measurement at A-02 ASC-ECU 
connector
(1) Disconnect the ASC-ECU connector, connect special tool 

ASC check harness (MB991997) to the harness-side 
connector, and then measure the resistance at the special 
tool connector side.
NOTE: Do not connect the special tool to ASC-ECU.

(2) Measure the resistance between the wheel speed sensor 

power supply terminal (signal terminal) No.36 and the body 
ground and between the wheel speed sensor ground 
terminal No.37 and the body ground.

OK: No continuity

Q: Is the check result normal?

YES : Go to Step 8.
NO (Not normal at the terminal No.36 or 37) : Go to Step 

6.

STEP 6. Connector check: A-02 ASC-ECU connector, 
C-129 intermediate connector, D-114 rear wheel speed 
sensor <LH> connector
Q: Is the check result normal?

YES : Go to Step 7.
NO :  Repair the defective connector.

STEP 7. Wiring harness check between A-02 ASC-ECU 
connector terminal No.36 and D-114 rear wheel speed 
sensor <LH> connector terminal No.1 and between A-02 
ASC-ECU connector terminal No.37 and D-114 rear wheel 
speed sensor <LH> connector terminal No.2

• Check for short circuit in rear wheel speed sensor <LH> cir-

cuit

Q: Is the check result normal?

YES : Replace the wheel speed sensor <RL> (Refer to 

P.35C-288

).

NO :  Repair the wiring harness.

AC611137 BY

ASC-ECU

MB991997

Check harness

A-02 ASC-ECU
harness connector

DIAGNOSIS

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ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-36

STEP 8. Voltage measurement at the A-02 ASC-ECU 
connector
(1) Disconnect the ASC-ECU connector, connect special tool 

ASC check harness (MB991997) to the ASC-ECU-side 
connector and harness-side connector, and then measure 
the voltage at the special tool connector side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between the wheel speed sensor 

power supply terminal (signal terminal) No.36 and body 
ground, and between the ground terminal No.37 and body 
ground.

OK:

Terminal No.36 and body ground: Approximately 

system voltage

Terminal No.37 and body ground: 1 volt or less

Q: Is the check result normal?

YES : Go to Step 9.
NO :  Go to Step 11.

STEP 9. Wiring harness check between A-02 ASC-ECU 
connector terminal No.36 and D-114 rear wheel speed 
sensor <LH> connector terminal No.1 and between A-02 
ASC-ECU connector terminal No.37 and D-114 rear wheel 
speed sensor <LH> connector terminal No.2.

• Check for open circuit in wheel speed sensor <RL> circuit

Q: Is the check result normal?

YES : Go to Step 10.
NO :  Repair the wiring harness.

STEP 10. Check for wheel speed sensor <RL> as a single 
unit
Refer to 

P.35C-289

.

Q: Is the check result normal?

YES : Go to Step 11.
NO :  Replace the wheel speed sensor <RL> (Refer to 

P.35C-288

).

STEP 11. Connector check: A-02 ASC-ECU connector, 
D-114 rear wheel speed sensor <LH> connector
Q: Is the check result normal?

YES : Go to Step 12.
NO :  Repair the defective connector.

AC611138AM

ASC-ECU

MB991997

A-02 ASC-ECU 
harness connector

Check harness

DIAGNOSIS

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ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-37

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

NOTE: The ABS warning light does not turn OFF in some 
cases unless the vehicle runs at 12 mph (20 km/h) or 
higher.

Q: Is DTC C1020 set?

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

(Refer to 

P.35C-287

).

NO :  Intermittent malfunction (Refer to GROUP 00 

− How 

to Use Troubleshooting/How to Cope with Intermittent 
Malfunctions 

P.00-15

).

DTC C102B Abnormality in RR wheel speed sensor circuit

Wheel Speed Sensor Circuit

ASC-ECU

FRONT 
WHEEL 
SPEED 
SENSOR 
(LH)

FRONT 
WHEEL 
SPEED 
SENSOR 
(RH)

REAR 
WHEEL 
SPEED 
SENSOR 
(LH)

REAR 
WHEEL 
SPEED 
SENSOR 
(RH)

DIAGNOSIS

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ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-38

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 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-283

, 

P.35C-282

 

and 

P.35C-284

).

.

OPERATION

• The wheel speed sensor is a kind of a pulse generator. It 

consists of encoders (a plate on which north and south pole 
sides of the magnets are arranged alternately) for detecting 
the wheel speed which rotates at the same speed of the 
wheels and wheel speed sensors. This sensor outputs fre-
quency pulse signals in proportion to the wheel speed.

• The pulse signals, which the wheel speed sensor creates, 

are sent to ASC-ECU. ASC-ECU uses the frequency of the 
pulse signals to determine the wheel speed.

.

DTC SET CONDITIONS

ASC-ECU monitors the voltage fluctuation in each wheel speed 
sensor circuit. If ASC-ECU detects the open or short circuit in 
the circuit, it will set a diagnostic trouble code.

.

AC901112

Connector: A-02

A-02 (B)

AF

AC901075BC

Connector: C-129

AC901080AN

Connector: D-133

D-133 (B)