Mitsubishi L200. Manual — part 449

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-52

YES :

Go to Step 8.

NO :

Replace the wheel speed sensor (Refer to

P.35C-141

.). Then go to Step 9.

STEP 8. Check whether the diagnosis code is
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 15 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 15 km/h
or higher.

Q: Is the diagnosis code No.C1207 set?

YES :

Replace the hydraulic unit (integrated with

ASTC-ECU) (Refer to

P.35C-140

.). Then go

to Step 9.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Cope with Intermittent

Malfunctions .).

STEP 9. Check whether the diagnosis code is
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 15 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 15 km/h
or higher.

Q: Is the diagnosis code No.C1207 set?

YES :

Return to Step 1.

NO :

This diagnosis is complete.

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-53

Code No.C1212: Wheel speed sensor (RR) (malfunction power circuit)

ACB00772

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

Wheel Speed Sensor Circuit

ASTC-ECU

FRONT WHEEL
SPEED SENSOR
(LH)

FRONT WHEEL
SPEED SENSOR
(RH)

REAR WHEEL
SPEED SENSOR
(LH)

REAR WHEEL
SPEED SENSOR
(RH)

AC800980

AG

Connector: A-48

(B)

AC600687CB

Connectors: C-29 <LHD>

16

10

13

4

1112

1 2 3

15

14

5

20

18

17

19

7

6

8 9

AC600635BE

Connector: C-29 <RHD>

16

10

13

4

1112

1 2 3

15

14

5

20

18

17

19

7

6

8 9

AC504324 AX

Connectors: F-10, F-12

F-10 (GR)

F-10 Harness connector
(harness side)

F-12 (B)

F-12

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-54

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 .).

• Before replacing the ECU, ensure that the

communication circuit is normal.

OPERATION

• A toothed ABS rotor generates a pulse signal as

it moves across the pickup field of each wheel
speed sensor.

• The wheel speed sensor transmit the frequency

of the pulses to the ASTC-ECU.

• The hydraulic unit assembly (integrated with

ASTC-ECU) modulates the amount of braking
force individually applied to each wheel cylinder.

DIAGNOSIS CODE SET CONDITION
Diagnosis code No.C1212 is set when the supply
voltage to wheel speed sensor has decreased.

PROBABLE CAUSES

Current trouble

• Damaged wiring harness and connectors

• Noise interference

• Wheel speed sensor malfunction

• ASTC-ECU malfunction

Past trouble

• Carry out diagnosis with particular emphasis on

wiring harness and connector failures between
ASTC-ECU and the wheel speed sensor. For
diagnosis procedures, refer to How to treat past
trouble (GROUP 00

− How to Cope with Intermit-

tent Malfunctions .).

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 3.

NO :

Repair the CAN bus lines (Refer to GROUP
54C

− CAN Bus Diagnostics Table .). On

completion, go to Step 2.

STEP 2. Diagnosis code recheck after resetting
CAN bus lines
(1) Erase the diagnosis code.
(2) Drive the vehicle at 15 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 15 km/h
or higher.

Q: Is the diagnosis code No.C1212 set?

YES :

Go to Step 3.

NO :

This diagnosis is complete.

STEP 3. M.U.T.-III data list
Check the following data list (Refer to

P.35C-131

.).

• Item No.04: RR wheel speed sensor

Q: Is the check result normal?

YES :

Go to Step 8.

NO :

Go to Step 4.

STEP 4. Connector check: A-48 ASTC-ECU
connector, C-29 intermediate connector, F-12
intermediate connector, F-10 rear wheel speed
sensor (RH) connector

Q: Is the check result normal?

YES :

Go to Step 5.

NO :

Repair the defective connector. Then go to
Step 9.

STEP 5. Voltage measurement at the A-48 ASTC-
ECU connector
(1) Disconnect the A-48 ASTC-ECU connector, the

F-10 rear wheel speed sensor (RH) connector.

(2) Measure the voltage between the A-48 ASTC-

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-55

ECU connector terminal No.20 and body earth.

OK: 1V or less

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Repair the wiring harness. Then go to Step
9.

STEP 6. Resistance measurement at the A-48
ASTC-ECU connector
(1) Disconnect the A-48 ASTC-ECU connector, the

F-10 rear wheel speed sensor (RH) connector.

(2) Measure the resistance between the A-48 ASTC-

ECU connector terminal No.20 and body earth.

OK: No continuity

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

Repair the wiring harness. Then go to Step
9.

STEP 7. Check for wheel speed sensor as a
single unit
Refer to

P.35C-141

.

Q: Is the check result normal?

YES :

Go to Step 8.

NO :

Replace the wheel speed sensor (Refer to

P.35C-141

.). Then go to Step 9.

STEP 8. Check whether the diagnosis code is
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 15 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 15 km/h
or higher.

Q: Is the diagnosis code No.C1212 set?

YES :

Replace the hydraulic unit (integrated with

ASTC-ECU) (Refer to

P.35C-140

.). Then go

to Step 9.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Cope with Intermittent

Malfunctions .).

STEP 9. Check whether the diagnosis code is
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 15 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 15 km/h
or higher.

Q: Is the diagnosis code No.C1212 set?

YES :

Return to Step 1.

NO :

This diagnosis is complete.