Mitsubishi L200. Manual — part 451

AC805612

BJ

Connector: C-144

(GR)

Harness connector
(harness side)

4

2

3

1

AC600688

Connectors: C-132 <LHD>

AD

C-132 (GR)

AC600635AB

Connector: C-132 <RHD>

C-132 (GR)

AC600687CX

Connectors: C-137, C-138 <LHD>

2

1

3

13

12

14

21

10

5

4

6

16

15

17

7 8 9

19

18

20

11

22

C-137, C-138

C-137, C-138

AC600623CZ

2

1

3

13

12

14

21

10

5

4

6

16

15

17

7 8 9

19

18

20

11

22

C-137, C-138

Connector: C-137, C-138 <RHD>

C-137, C-138

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-60

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Diagnose
the CAN bus lines before the diagnosis code
(Refer to GROUP 54C

− CAN Bus Diagnostics

Table ).
OPERATION

• The G and yaw rate sensor is energized by the

ignition switch (IG1) and the G and yaw rate sen-
sor terminal 1.

• The G and yaw rate sensor output signal is sent

to the ASTC-ECU via the private CAN bus line.

DIAGNOSIS CODE SET CONDITION
The diagnosis code is set if the first G and yaw rate
sensor check is not completed within the specified
time although ASTC-ECU input voltage is normal
when the ignition switch is turned ON.

PROBABLE CAUSES

• Malfunction of the G and yaw rate sensor

• Damaged wiring harness or connector

• Malfunction of the hydraulic unit (integrated with

ASTC-ECU)

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

Q: Is the diagnosis code No.C1223 set?

YES :

Go to Step 3.

NO :

This diagnosis is complete.

STEP 3. Connector check: C-144 G and yaw rate
sensor connector, C-132 joint connector, C-137
joint connector and C-138 joint connector

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Repair the defective connector. Then go to
Step 9.

STEP 4. Resistance measurement at the C-144 G
and yaw rate sensor connector
(1) Disconnect the connector C-144 G and yaw rate

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-61

sensor connector and measurement at the
harness-side connector.

(2) Measure the resistance between the C-144 G

and yaw rate sensor connector terminal No.4 and
body earth.

OK: Continuity exists (2

Ω or less)

Q: Is the check result normal?

YES :

Go to Step 6.

NO :

Go to Step 5.

STEP 5. Resistance measurement at the C-137
joint connector
(1) Disconnect the connector C-137 joint connector

and measurement at the harness-side connector.

(2) Measure the resistance between the C-144 G

and yaw rate sensor connector terminal No.19
and body earth.

OK: Continuity exists (2

Ω or less)

Q: Is the check result normal?

YES :

An open circuit may be present. Repair the

harness wire between C-138 joint connector
terminal No.13 and C-144 G and yaw rate
sensor connector terminal No.4. Then go to
Step 9.

NO :

An open circuit may be present. Repair the
harness wire between C-137 joint connector
terminal No.19 and body earth. Then go to
Step 9.

STEP 6. Voltage measurement at the C-144 G and
yaw rate sensor connector
(1) Disconnect the connector C-144 G and yaw rate

sensor connector and measurement at the
harness-side connector.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between the C-144 G and

yaw rate sensor connector terminal No.1 and
body earth.

OK: System voltage

Q: Is the check result normal?

YES :

Go to Step 7.

NO :

An open circuit may be present. Repair the
wiring harness between the C-144 G and
yaw rate sensor connector terminal No.1
and the C-132 joint connector terminal
No.19. Then go to Step 9.

STEP 7. Check whether the diagnosis code is
reset.
Check again if the diagnosis code is set.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.
(6) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is code No.C1223 set?

YES :

Replace the G and yaw rate sensor (Refer

to

P.35C-142

). Then go to Step 8.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Cope with Intermittent

Malfunction ).

STEP 8. Check whether the diagnosis code is
reset.
Check again if the diagnosis code is set.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.
(6) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is code No.C1223 set?

YES :

Replace the hydraulic unit (integrated with

ASTC-ECU) (Refer to

P.35C-140

). Then go

to Step 9.

NO :

The procedure is complete.

STEP 9. Recheck for diagnosis code.
Check again if the diagnosis code is set.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.
(6) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is code No.C1223 set?

YES :

Go to Step 1.

NO :

The procedure is complete.

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-62

Code No.C1225: Wheel Speed Sensor Malfunction (Abnormality in tyre size)

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 amount of voltage generated at each wheel

is determined by the clearance between the ABS
rotor teeth and the wheel speed sensor, and by
the speed of rotation.

• The wheel speed sensors transmit the frequency

of the voltage pulses and the amount of voltage
generated by each pulse 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
This diagnosis code is set when the average speed
of the front wheels differs from that of the rear wheel
by 20 % or more after the vehicle speed exceeds 30
km/h.

PROBABLE CAUSES

• Installation of different size tyres

• Damaged wiring harness or connector

• ASTC-ECU malfunction

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 30 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 30 km/h
or higher.

Q: Is the diagnosis code No.C1225 set?

YES :

Go to Step 3.

NO :

This diagnosis is complete.

STEP 3. Check the installation condition of the
wheel and tyres.

Q: Is the check result normal?

YES :

Go to Step 4.

NO :

Install the correct size tyres. Then go to
Step 5.

STEP 4. Check whether the diagnosis code is
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 30 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 30 km/h
or higher.

Q: Is the diagnosis code No.C1225 set?

YES :

Replace the hydraulic unit assembly

(integrated with ASTC-ECU) (Refer to

P.35C-140

.). Then go to Step 5.

NO :

Intermittent malfunction (Refer to GROUP
00

− How to Cope with Intermittent

Malfunctions .).

STEP 5. Check whether the diagnosis code is
reset.
(1) Erase the diagnosis code.
(2) Drive the vehicle at 30 km/h or more.

NOTE: The ABS warning lamp does not turn OFF
in some cases unless the vehicle runs at 30 km/h
or higher.

Q: Is the diagnosis code No.C1225 set?

YES :

Return to Step 1.

NO :

The procedure is complete.

TROUBLESHOOTING

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-63

Code No.C1226: Control solenoid valve (FR) pressure holding system

Code No.C1236: Control solenoid valve (FL) pressure holding system

Code No.C1246: Control solenoid valve (RR) pressure holding system

Code No.C1256: Control solenoid valve (RL) pressure holding system

Code No.C1231: Control solenoid valve (FR) decompressing system

Code No.C1241: Control solenoid valve (FL) pressure reducing system

Code No.C1251: Control solenoid valve (RR) pressure reducing system

Code No.C1261: Control solenoid valve (RL) decompressing system

Code No.C1300: Linear valve (secondly)

Code No.C1310: Linear valve (primary)

CAUTION

If there is any problem in the CAN bus lines, an
incorrect diagnosis code may be set. Diagnose
the CAN bus lines before the diagnosis codes
(Refer to GROUP 54C

− CAN Bus Diagnostics

Table ).
OPERATION

• The ASTC-ECU contains the power supply circuit

for the solenoid valve. The solenoid valve is ener-
gized by the valve relay, which is incorporated in
the ASTC-ECU.

• The valve relay, which is incorporated in the

ASTC-ECU, is always energizing the solenoid
valve unless the initial check is in progress when
the ignition switch is turned on.

• The ASTC-ECU activates the solenoid valve by

turning on its driving transistor.

DIAGNOSIS CODE SET CONDITIONS
These diagnosis codes will be set under the cases
below.

Code No.C1226, C1231, C1236, C1241, C1246,

C1251, C1256, C1261

• The output of the each solenoid valve does not

change when the solenoid valve is "ON" and the
solenoid valve monitor is "ON"

Code No.C1300, C1310

• The linear valve monitor is "OFF" when the linear

valve has an open circuit.

• The linear valve monitor is "OFF" when the linear

valve is "ON"

PROBABLE CAUSES
The most likely causes for these diagnosis codes to
set are:

• Malfunction of the hydraulic unit assembly (inte-

grated with ASTC-ECU)

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. Check whether the diagnosis code is
reset.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.
(6) Turn the ignition switch to the "LOCK" (OFF)

position.

Q: Is code No.C1226, C1231, C1236, C1241, C1246,

C1251, C1256, C1261, C1300 or C1310 set?
YES :

Replace the hydraulic unit assembly

(integrated with ASTC-ECU) (Refer to

P.35C-140

). Then go to Step 3.

NO :

It can be assumed that this malfunction is
intermittent. Refer to GROUP 00, How to
Use Troubleshooting/Inspection Service
Points

− How to Cope with Intermittent

Malfunction .

STEP 3. Check whether the diagnosis code is
reset.
Check again if the diagnosis code is set.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the diagnosis code.
(3) Turn the ignition switch to the "LOCK" (OFF)

position.

(4) Turn the ignition switch to the "ON" position.
(5) Check if the diagnosis code is set.