Mitsubishi L200. Manual - part 444

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 AY

Connectors: F-11, F-12

F-11 (B)

F-11 Harness connector
(harness side)

F-12 (B)

F-12

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-32

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 voltage pulse 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.C1215 is set when signal is not 
input due to breakage of the wire of the wheel speed 
sensor without the output of the code No.C1217.

PROBABLE CAUSES

Current trouble

• Damaged wiring harness and connectors

• 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.C1215 set?

YES : 

Go to Step 3.

NO : 

The procedure is complete.

STEP 3. M.U.T.-III diagnosis code
Check that the diagnosis code No.C1217 are also 
set.

Q: Is the diagnosis code No.C1217 also set?

YES : 

Perform the diagnosis for the diagnosis 

code No.C1217 (Refer to 

P.35C-56

.).

NO : 

Go to Step 4.

STEP 4. M.U.T.-III data list
Check the following data list (Refer to 

P.35C-131

.).

• Item No.03: RL wheel speed sensor

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Go to Step 5.

STEP 5. Connector check: A-48 ASTC-ECU 
connector, C-29 intermediate connector, F-12 
intermediate connector, F-11 rear wheel speed 
sensor (LH) connector

Q: Is the check result normal?

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-33

YES : 

Go to Step 6.

NO : 

Repair the defective connector. Then go to 
Step 9.

STEP 6. Resistance measurement at the A-48 
ASTC-ECU connector
(1) Disconnect the A-48 ASTC-ECU connector.
(2) Measure the resistance between A-48 ASTC-

ECU connector terminal No.8 and terminal No.9.

OK: 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.C1215 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.C1215 set?

YES : 

Return to Step 1.

NO : 

This diagnosis is complete.

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-34

Code No.C1201: Wheel speed sensor (FR) (signal short 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)

AC501971AL

Connector: A-125

A-125 (B)

A-125 Harness
connector
(harness side)

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-35

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 voltage pulse 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.C1201 is set if any abnormal volt-
age from the wheel speed sensor is detected without 
the outputs of the codes No.C1200 or C1202.

PROBABLE CAUSES

Current trouble

• Damaged wiring harness and connectors

• Teeth lack or clogging of the ABS rotor

• Malfunction of the front hub assembly

• 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.C1201 set?

YES : 

Go to Step 3.

NO : 

This diagnosis is complete.

STEP 3. M.U.T.-III diagnosis code
Check that the diagnosis codes No.C1200 or C1202 
is also set.

Q: Are the diagnosis codes No.C1200 or C1202 also 

set?
YES : 

Perform the diagnosis for the diagnosis 

codes No.C1200 or C1202 (Refer to 

P.35C-

23

, 

P.35C-47

.).

NO : 

Go to Step 4.

STEP 4. M.U.T.-III data list
Check the following data list (Refer to 

P.35C-131

.).

• Item No.02: FR wheel speed sensor

Q: Is the check result normal?

YES : 

Go to Step 12.

NO : 

Go to Step 5.

STEP 5. Check for wheel speed sensor (FR) 
installation
Check how the wheel speed sensor (FR) is installed 
correctly (Disconnection of wheel speed sensor (FR), 
loose mounting bolt, etc.).

Q: Is the check result normal?

YES : 

Go to Step 6.

NO : 

Reinstall the wheel speed sensor (FR) 
correctly (Refer to 

P.35C-141

.). Then go to 

Step 13.

STEP 6. Check for wheel speed sensor (FR) 
output current
Refer to 

P.35C-135

.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Replace the wheel speed sensor (FR) 
(Refer to 

P.35C-141

.). Then go to Step 13.