Mitsubishi Galant 9G. Manual — part 1623

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-76

STEP 5. Measure the voltage at ABS-ECU connector A-02.
(1) Disconnect the connector A-02, and connect special tool

ABS Check Harness (MB991970) to the wiring
harness-side connector.
NOTE: Do not connect special tool ABS Check Harness
(MB991970) to the ABS-ECU.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 20 and ground. It

should be approximately 12 volts (battery positive voltage).

Q: Is the voltage approximately 12 volts (battery positive

voltage)?
YES : Go to Step 7.
NO : Go to Step 6.

AC306403

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

A-02(GR)

CONNECTOR: A-02

HYDRAULIC UNIT
(WITH BUILT-IN ABS-ECU)

AJ

ABS-ECU

MB991970

CHECK CONNECTOR

A-02 HARNESS
CONNECTOR

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-77

STEP 6. Check ABS-ECU connector A-02, junction block
connectors C-214, C-215 and ignition switch connector
C-318 for loose, corroded or damaged terminals, or
terminals pushed back in the connector.

• ABS-ECU connector A-02

• Junction block connectors C-214 and C-215

AC306406

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

A-02 HARNESS CONNECTOR
(HARNESS SIDE)

AB

A-02 (GR)

CONNECTOR: A-02

HYDRAULIC UNIT
(WITH BUILT-IN ABS-ECU)

AC305416AJ

C-214

CONNECTORS: C-214, C-215

C-215

1

3 4

2

6

5

C-214

6

1

7

2

9

8

10

3

5

12

11

4

1314

C-215

JUNCTION BLOCK
(FRONT VIEW)

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-78

• Ignition switch connector C-308

Q: Are the connectors and terminals in good condition?

YES : An open or short circuit may be present in the power

supply line to the ABS-ECU. Repair the wiring
harness between ABS-ECU connector A-02 terminal
20 and ignition switch connector C-308 terminal 4. Go
to Step 8.

NO : Repair or replace the damaged component(s). Refer

to GROUP 00E, Harness Connector Inspection

P.00E-2

. Then go to Step 8.

STEP 7. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the DTC.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
(4) Turn the ignition switch to the "ON" position.
(5) Check if the DTC is set.
(6) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC C1860 or C1861 set?

YES : Replace the hydraulic unit (integrated with

ABS-ECU). Then go to Step 8.

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

P.00-14

.

AC305235AG

CONNECTOR: C-308

C-308

2
5

4

1

6

3

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-79

STEP 8. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Turn the ignition switch to the "ON" position.
(2) Erase the DTC.
(3) Turn the ignition switch to the "LOCK" (OFF) position.
(4) Turn the ignition switch to the "ON" position.
(5) Check if the DTC is set.
(6) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is DTC C1860 or C1861 set?

YES : Go to Step 1.
NO : The procedure is complete.

DTC U1073: Bus off

CAUTION

• If DTC U1073 is set in the ABS-ECU, always

diagnose the CAN main bus line. If there is
any fault in the CAN bus lines, an incorrect
DTC may be set.

• Whenever the ECU is replaced, ensure that

the communication circuit is normal.

.

TROUBLE JUDGMENT

This code is stored when the ABS-ECU has ceased
the CAN communication (bus off). Then, if a penalty
mode is entered after approximately five minutes, the
regular data transmission from the ABS-ECU will be
cancelled.

.

TROUBLESHOOTING HINTS (The most
likely causes for these DTCs are to set
are:)

• Damaged wiring harness or connector

• Malfunction of the hydraulic unit (integrated with

ABS-ECU)

.

DIAGNOSIS

Required Special Tools:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: MUT-III USB Cable

• MB991910: MUT-III Main Harness A

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827