Mitsubishi Colt Ralliart. Manual — part 642

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-113

Operation pattern of items 01 to 08

CHECK AT ECU TERMINALS

M1357001400011

TERMINAL VOLTAGE CHECK

1. Operate the lock lever to disconnect the

ASC-ECU harness connector as shown in the
figure.

2. Connect the ABS check harness (Special tool:

MB991984) to measure the voltages between
each check connector terminal and earth terminal
(No. 43 or 46).

NOTE: When the ignition switch is turned to "ON,"
ASC-ECU performs the initial check for approx. 3
seconds. Do not measure the terminal voltage
during that period.

3. Terminal layout is shown in the figure.

AC400776

Complete

MUT-III actuator test
(Item No.01, 02, 03, 04)
start

1s

2s

Approx. 0.05s

Approx. 0.01s

Solenoid valve
(ABS)

AC

Hold

Pressure decrease

Pressure increase

Cut valve
Suction valve
(TCL/Stability
control)

Complete

MUT-III actuator test
(Item No.05, 06, 07, 08)
start

Pump motor

Drives

Stops

Pressure increase

Hold

Pressure decrease

AC601007AB

A-05: ASC-ECU connector

AC601121AB

MB991984

Check connector

ASC-ECU

ASC-ECU harness connector

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-114

Terminal
No.

Check items

Check conditions

Normal condition

6

Stop lamp switch input

Brake switch: OFF (Release the brake pedal.)

Approximately 0 V

Brake switch: ON (Depress the brake pedal.)

System voltage

8

Wheel speed sensor (RR)
input

Ignition switch: ON

0.4 to 1.3 V

10

Wheel speed sensor (RL)
input

Ignition switch: ON

0.4 to 1.3 V

11

Wheel speed sensor (RL)
power supply

Ignition switch: ON

Voltage that is
approx. 0.7 V lower
than the ASC-ECU
power supply
voltage

13

Wheel speed sensor (FL)
input

Ignition switch: ON

0.4 to 1.3 V

23

Brake switch input

Brake switch: ON (Release the brake pedal.)

Approx. 0 V

Brake switch: OFF (Depress the brake pedal.)

System voltage

27

Parking brake switch input Parking brake switch: ON

System voltage

Parking brake switch: OFF

Approx. 0 V

28

Wheel speed sensor (FR)
input

Ignition switch: ON

0.4 to 1.3 V

29

Wheel speed sensor (FR)
power supply

Ignition switch: ON

Voltage that is
approx. 0.7 V lower
than the ASC-ECU
power supply
voltage

30

Wheel speed sensor (RR)
power supply

Ignition switch: ON

Voltage that is
approx. 0.7 V lower
than the ASC-ECU
power supply
voltage

32

Brake fluid level switch
input

Brake fluid level switch: ON

Approx. 0 V

Brake fluid level switch: OFF

System voltage

34

Wheel speed sensor (FL)
power supply

Ignition switch: ON

Voltage that is
approx. 0.7 V lower
than the ASC-ECU
power supply
voltage

40

ASC-ECU power supply

Ignition switch: ON

System voltage

43

ASC-ECU earth, solenoid
valve earth

Always

0 V

44

Solenoid valve power
supply (fusible link No. 5)

Always

System voltage

45

Motor power supply
(fusible link No. 3)

Always

System voltage

46

Motor earth

Always

0 V

Main

Index

Group

TOC

TROUBLESHOOTING

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-115

CONTINUITY CHECK AT WIRING
HARNESS-SIDE CONNECTOR

1. Disconnect the A-05 connector, and connect the

ABS check harness (Special tool: MB991984) to
the harness-side connector.
NOTE: Do not connect the ABS check harness
(Special tool: MB991984) to the ASC-ECU.

2. Check the continuity between terminals shown in

the chart below.

3. Terminal layout is shown in the figure.

AC601085AE

MB991984

ASC-ECU

Check connector

ASC-ECU harness connector

Connector terminal number

Signal

Normal condition

43

− body earth

Earth

Continuity exists (2

Ω or less)

46

− body earth

Earth

Continuity exists (2

Ω or less)

Main

Index

Group

TOC

ON-VEHICLE SERVICE

ACTIVE STABILITY CONTROL SYSTEM (ASC)

35C-116

ON-VEHICLE SERVICE

HYDRAULIC UNIT (HU) CHECK

M1357001600015

1. Raise the vehicle using a jack and support the

specified points with a rigid rack.

CAUTION

Before connecting or disconnecting M.U.T.-III,
always turn the ignition switch to the LOCK
(OFF) position.
2. Before setting M.U.T.-III, turn the ignition key to

the LOCK (OFF) position.

3. Confirm that the shift lever is in the neutral

position, and then start the engine.

4. Use the M.U.T.-III to perform the actuator test with

depressing the brake pedal. When carrying out
the actuator tests, rotate the wheel by hands to
confirm that the braking force changes.
NOTE: During the actuator test, the brake warn-
ing lamp, ABS warning lamp and ASC indicator
lamp illuminate and the ABS/ASC control is pro-
hibited
NOTE: When ASC-ECU is disabled due to the
fail-safe function, the M.U.T.-III actuator test can-
not be performed.

Main

Index

Group

TOC