Mitsubishi Outlander XL. Manual — part 656

STEP 7. Resistance measurement at A-02 ASC-ECU
connector

ZC601293 0007

ASC-ECU

MB991997

Check harness

A-02 ASC-ECU
harness connector

(1)

Disconnect the ASC-ECU connector, connect special tool
MB991997 to the harness-side connector, and then measure
the resistance at the special tool connector side.

NOTE:

Do not connect the special tool MB991997 to ASC-

ECU.

(2)

Resistance between the wheel speed sensor power supply
terminal (signal terminal) No. 43/the ground terminal No. 42
and the body ground

OK: No continuity

Q:Is the check result normal?

YES:

Go to Step 10.

NO (Not normal at the terminal No. 43 or 42):

Go to Step

8.

STEP 8. Connector check: A-02 ASC-ECU connector, D-133
wheel speed sensor <RR> connector

Q:Is the check result normal?

YES:

Go to Step 9.

NO:

Repair the defective connector.

STEP 9. Wiring harness check between A-02 ASC-ECU
connector terminal No. 43/42 and D-133 wheel speed sensor
<RR> connector terminal No. 1/2

｠

Check for short circuit in wheel speed sensor <RR> circuit

Q:Is the check result normal?

YES:

Replace the wheel speed sensor <RR>.

NO:

Repair the wiring harness.

ACTIVE SKID CONTROL SYSTEM (ASC)

35C-31

DIAGNOSIS

STEP 10. Voltage measurement at the A-02 ASC-ECU
connector

ZC601292 0004

ASC-ECU

MB991997

Check harness

A-02 ASC-ECU
harness connector

(1)

Disconnect the ASC-ECU connector, connect special tool
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 circuit
power supply terminal (signal terminal) No. 43 and the body
ground.

OK: Approximately battery voltage

Q:Is the check result normal?

YES:

Go to Step 13.

NO:

Go to Step 11.

STEP 11. Connector check: A-02 ASC-ECU connector,
D-133 wheel speed sensor <RR> connector

Q:Is the check result normal?

YES:

Go to Step 12.

NO:

Repair the defective connector.

STEP 12. Wiring harness check between A-02 ASC-ECU
connector terminal No. 43/42 and D-133 wheel speed sensor
<RR> connector terminal No. 1/2

｠

Check for open circuit in wheel speed sensor <RR> circuit

Q:Is the check result normal?

YES:

Replace the wheel speed sensor.

NO:

Repair the wiring harness.

STEP 13. Check for wheel speed sensor as a single unit
Refer to P.35C-197.

Q:Is the check result normal?

YES:

Go to Step 14.

NO:

Replace the wheel speed sensor.

STEP 14. Check whether the diagnostic trouble code is
reset.

(1)

Erase the diagnostic trouble code.

(2)

Drive the vehicle at 12mph (20 km/h) or more.

NOTE:

The ABS warning light does not turn OFF in some

cases unless the vehicle runs at 12mph (20 km/h) or
higher.

35C-32

ACTIVE SKID CONTROL SYSTEM (ASC)

DIAGNOSIS

Q:Is DTC C102B set?

YES:

Replace the ASC-ECU.

NO:

Intermittent malfunction (Refer to GROUP 00 - How to

Cope with Intermittent Malfunction P.00-15).

DTC C1011: Abnormality in FL wheel speed sensor signal

M13506100014USA0000010000

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)

If there is any problem in the CAN bus lines, an incorrect
diagnostic trouble code may be set. Prior to this diagnosis,
diagnose the CAN bus lines. (Refer to GROUP 54D, Trouble
code diagnosis P.54D-17).

CIRCUIT 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
frequency 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.

ACTIVE SKID CONTROL SYSTEM (ASC)

35C-33

DIAGNOSIS

DTC SET CONDITIONS
ASC-ECU monitors the signals from each wheel speed sensor
while the vehicle is being driven. If any fault below is found in
these sensor signals, ASC-ECU will set the relevant diagnostic
trouble code.

｠

Irregular change in the wheel speed sensor signal

｠

Wheel speed sensor signal continuously indicates high value.

PROBABLE CAUSES

Current trouble

｠

Excessive gap between the wheel speed sensor and the
wheel speed detection encoder

｠

Adhesion of foreign materials on the wheel speed sensor

｠

Adhesion of foreign materials on the wheel speed detection
encoder

｠

Wheel bearing malfunction

｠

Malfunction of wheel speed sensor

｠

Damaged wiring harness and connectors

｠

External noise interference

｠

Improper installation of the wheel speed sensor

｠

Deformation of the wheel speed detection encoder

｠

ASC-ECU malfunction

｠

Disturbance of magnetization pattern for wheel speed
detection encoder

Past trouble

｠

When the diagnostic trouble code No. C100A is also set, carry
out diagnosis with particular emphasis on wiring harness and
connector failures between ASC-ECU and the wheel speed
sensor. For diagnosis procedures, refer to How to treat past
trouble (Refer to GROUP 00 - How to Cope with Intermittent
Malfunction P.00-15).

｠

When the diagnostic trouble code No. C100A is not set, the
following conditions may be present:

｠

Right or/and left wheels are rotated.

｠

Unstable vehicle attitude

｠

External noise interference

｠

Vehicle ran with the parking brake applied.

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

｠

MB991997: ASC check harness

STEP 1. M.U.T.-III CAN bus diagnostics
Use scan tool to diagnose the CAN bus lines.

Q:Is the check result normal?

35C-34

ACTIVE SKID CONTROL SYSTEM (ASC)

DIAGNOSIS