Mitsubishi Galant 9G. Manual - part 441

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS

TSB Revision

TRACTION CONTROL SYSTEM (TCL)

13D-32

.

CIRCUIT OPERATION

ABS/TCL-ECU terminal 6 is grounded every time the 
TCL switch is pressed. ABS/TCL-ECU monitors this 
operation state and turns the TCL ON or OFF.

.

COMMENT

The cause is probably an open-circuit in the TCL 
switch circuit.

.

TROUBLESHOOTING HINTS

• Malfunction of the TCL switch.

• Damaged harness or connector.

• Malfunction of the ABS/TCL-ECU.

AC305209AB

A-02 (GR)

CONNECTOR: A-02 

A-02 HARNESS CONNECTOR:

COMPONENT SIDE

AC305232AU

CONNECTORS: C-29, C-131

C-29

C-131(GR)

C-29 MALE SIDE

CONNECTOR

C-131 HARNESS

CONNECTOR:

COMPONENT SIDE

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS

TSB Revision

TRACTION CONTROL SYSTEM (TCL)

13D-33

DIAGNOSIS

Required Special Tools:

• MB991223: Harness Set

• MB991970: ABS Check Harness

STEP 1. Measure the terminal voltage at ABS/TCL-ECU 
connector A-02.
(1) Disconnect the ABS/TCL-ECU connector A-02.

(2) Connect special tool MB991970 between the 

ABS/TCL-EUC and the body-side harness connector.

(3) Turn the ignition switch to the "ON" position.
(4) Measure the terminal voltage between special tool 

MB991970 connector terminal 6 (ABS/TCL-ECU connector 
A-02 terminal 6) and ground.

• When the TCL switch is not pressed, the voltage should 

measure battery positive voltage (approximately 12 
volts).

• When the TCL switch is pressed, the voltage should 

measure 1 volt or less. 

(5) Turn the ignition switch to the "LOCK" (OFF) position.
(6) Disconnect special tool MB991970 between the 

ABS/TCL-ECU and the body-side harness connector.

(7) Connect the ABS/TCL-ECU connector A-02.
Q: Is the terminal voltage battery terminal voltage when the 

TCL switch is not pressed, and is the terminal voltage 1 
volt or less when the TCL switch is pressed?
YES : Go to Step 6.
NO :  Go to Step 2.

AC305209AB

A-02 (GR)

CONNECTOR: A-02 

A-02 HARNESS CONNECTOR:

COMPONENT SIDE

AC307168

19

2

18

1

8

9

7

6

5

4

3

10

11   

25

15

16

17

27

28

26

12

13

14

23

24

22 21 20

AB

ABS/TCL-ECU

MB991970

BODY SIDE
HARNESS

SPECIAL TOOL
28-PIN CONNECTOR
(ABS/TCL-ECU CONNECTOR A-02)

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS

TSB Revision

TRACTION CONTROL SYSTEM (TCL)

13D-34

STEP 2. Check the TCL switch.
(1) Remove the TCL switch. (Refer to 

P.13D-48

).

(2) Connect an ohmmeter to the TCL switch between terminals 

1 and 2.

(3) Check for continuity between terminals 1 and 2 when the 

TCL switch is operated.

• There is no continuity between terminals 1 and 2 when 

the TCL switch is not pressed.

• There is continuity between terminals 1 and 2 when the 

TCL switch is pressed.

Q: Is there no continuity between terminals 1 and 2 when 

the TCL switch is not pressed, and is there continuity 
when the TCL switch is pressed?
YES : Install the TCL switch. (Refer to 

P.13D-48

). Then go 

to Step 6.

NO :  Replace the TCL switch. (Refer to 

P.13D-48

). Then 

go to Step 7.

AC307176AB

C-131 TCL SWITCH

CONNECTOR

TRACTION CONTROL SYSTEM (TCL) DIAGNOSIS

TSB Revision

TRACTION CONTROL SYSTEM (TCL)

13D-35

STEP 3. Check ABS/TCL-ECU connector A-02, 
intermediate connector C-29 and TCL switch connectors 
C-131 for loose, corroded or damaged terminals, or 
terminals pushed back in the connector.
Q: Are there connectors and terminals in good condition?

YES : Go to Step 4.
NO :  Repair or replace the faulty connector. (Refer to 

GROUP 00E, Harness Connector Inspection 

P.00E-2

). Then go to Step 7.

AC305209AB

A-02 (GR)

CONNECTOR: A-02 

A-02 HARNESS CONNECTOR:

COMPONENT SIDE

AC305232AU

CONNECTORS: C-29, C-131

C-29

C-131(GR)

C-29 MALE SIDE

CONNECTOR

C-131 HARNESS

CONNECTOR:

COMPONENT SIDE