Mitsubishi L200. Manual - part 437

GENERAL INFORMATION

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-4

GENERAL INFORMATION

M1355000200193

Active Stability & Traction Control System (ASTC) is 
available as optional equipment.

• ASTC is a system combining the functions of 

Active Stability Control System (ASC) and Active 
Traction Control System (ATC).

• When ATC detects the slip of the driving wheel 

(ex. during startup on low 

µ road), it automatically 

applies the brakes to the slipping driving wheel. 
At the same time, ATC reduces the engine output 
and prevents the wheel spin when it determines 
that the engine torque is too high for the road sur-
face 

µ.

• When the ASC determines that the vehicle is in a 

dangerous condition, it reduces the engine output 
and applies brake force to four wheels independ-
ently to control the vehicle behaviour, avoiding 
the critical state.

NOTE: On vehicles with ASC, the ASTC-ECU con-
trols ABS as well.

CONSTRUCTION DIAGRAM

AC805501

AC509302

AB

1

1

2

13

15

3

4

5

14

6, 8, 16

9

10

12

11

7

Name of part

Number

Outline of function

Sensor

Wheel speed sensor

1

Send alternating current signals at frequencies which are 
proportional to the rotation speeds of each wheel to the 
ASTC-ECU.

Stop lamp switch

2

Sends a signal to the ASTC-ECU to indicate whether the 
brake pedal is depressed or not.

G and yaw rate sensor

3

It detects the acceleration in cross and lateral direction, 
and yaw rate of the vehicle. Then it sends a signal through 
the CAN bus line to the ASTC-ECU.

Steering wheel sensor

4

Detects the steering wheel angle, and sends a signal to 
the ASTC-ECU through the CAN bus line.

ASC switch

5

Sends a signal to the ASTC-ECU to turn on and off the 
active stability control and traction control (engine control 
only).

Pressure sensor

6

Is incorporated in the hydraulic unit, and informs the 
ASTC-ECU of the brake fluid pressure in the master 
cylinder.

Rear differential lock 
detection switch < 
Vehicles with rear 
differential lock>

7

ASTC-ECU detects the rear differential lock state.

Actuator Hydraulic unit

8

Drives the solenoid valves according to signals from the 
ASTC-ECU in order to control the brake hydraulic 
pressure for each wheel.

Brake warning lamp

9

Used as the warning lamp for the parking brake, brake 
fluid level, and EBD control. For the EBD control, this 
warning lamp informs the driver of the system status by 
turning on and off the lamp according to the signal from 
ASTC-ECU.

ABS warning lamp

10

Illuminates in response to signals from the ASTC-ECU 
when a problem develops in the system.

ASTC indicator lamp

11

Receives a signal from the ASTC-ECU, and flashes to 
inform the driver that the system is operating, or 
illuminates to inform the driver of system failure.

ASTC OFF indicator 
lamp

12

Receives a signal from the ASTC-ECU, and illuminates to 
inform the driver that the system is not operating or 
defective, or flashes to inform system over heat.

Diagnosis connector

13

Sets the diagnosis codes and allows communication with 
the M.U.T.-III.

A/T-ECU

*

14

Sends the gear condition to ASTC-ECU.

Engine-ECU

15

Receives a signal from the ASTC-ECU to control the 
engine output.

Active Stability & Traction Control 
System control unit (ASTC-ECU)

16

Controls actuators (described above) based on the signals 
coming from each sensor.
Controls the self-diagnostics and fail-safe functions.
Controls the diagnostic function (M.U.T.-III compatible).

GENERAL INFORMATION

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-5

NOTE: 

*

A/T

SERVICE SPECIFICATIONS

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-6

SCHEMATIC DIAGRAM

AC808008AB

G and yaw rate sensor

              : CAN-bus line
*  : A/T

Combination meter
  ABS warning lamp
  Brake warning lamp
  ASTC indicator lamp
  ASTC OFF indicator lamp

Steering wheel sensor

Front-left wheel speed sensor

Front-right wheel speed sensor

Rear-left wheel speed sensor

Rear-right wheel speed sensor

ASC switch

Engine-ECU and A/T-ECU *

Engine

A/T *
or
M/T

Hydraulic unit
(integrated with ASTC-ECU)

Stop lamp switch

Back lamp switch

Rear differential
lock-ECU *

1

1

2

Rear differential lock
detection switch *

2

1

*  : Vehicles with rear differential lock system

2

SERVICE SPECIFICATIONS

M1355000400045

Item

Standard value

Wheel speed sensor current mA

5 

− 9 or 11 − 17

Wheel speed sensor insulation resistance M

Ω

1.5 or more

SPECIAL TOOLS

ACTIVE STABILITY & TRACTION CONTROL SYSTEM (ASTC)

35C-7

SPECIAL TOOLS

M1355005800361

Tool

Number

Name

Use

MB991910

MB991826

MB991955

MB991911

MB991824

MB991827

MB991825

a

b

c

d

e

f

DO NOT USE

MB991955

a. MB991824
b. MB991827
c. MB991910
d. MB991911
e. MB991825
f. MB991826

M.U.T.-III sub-assembly

a. Vehicle 

Communication 
Interface (V. C. I.)

b. M.U.T.-III USB cable
c. M.U.T.-III main 

harness A (Vehicles 
with CAN 
communication 
system)

d. M.U.T.-III main 

harness B (Vehicles 
without CAN 
communication 
system)

e. M.U.T.-III 

measurement adapter

f. M.U.T.-III trigger 

harness

For vehicles with CAN 
communication, use 
M.U.T.-III main harness 
A to send simulated 
vehicle speed. If you 
connect M.U.T.-III main 
harness B instead, the 
CAN communication 
does not function 
correctly.
ASTC check (Diagnosis 
code display, and data list 
display by M.U.T.-III)

MB991709

Wiring harness set

Checking the ASTC-ECU 
and output current 
measure at the wheel 
speed sensor

TROUBLESHOOTING

STANDARD FLOW OF DIAGNOSTIC 
TROUBLESHOOTING

M1355000900084

Refer to GROUP 00, How to Use Troubleshooting/

Inspection Service Points .

CAUTION