Mitsubishi Galant. Manual — part 522

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-21

SYMPTOMS

INSPECTION
PROCEDURE NO.

REFERENCE PAGE

Communication between the scan tool and the whole
system is not possible.

-

1

3A

−

Diagnosis

P.13A-5

.

13B

−

Diagnosis

P.13A-5

.

Communication between the scan tool and the ABS-
ECU is not possible.

1

P.35B-22

When the ignition key is turned to "ON" (Engine
stopped), The ABS warning light does illuminate.

2

P.35B-27

The ABS warning light remains illuminated after the
engine is started.

3

P.35B-31

Faulty ABS operation

4

P.35B-37

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-22

SYMPTOM PROCEDURES

INSPECTION PROCEDURE 1: Communication with scan tool is not possible. (Communication with
ABS only is not possible.)

AC003924

Data Link Connector Circuit

AB

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-23

CIRCUIT OPERATION

•

The diagnostic output is made from the ABS-
ECU (terminal 7) to the diagnostic output terminal
(terminal 7) of the data link connector.

•

When the data link connector's diagnostic test
mode control terminal (terminal 1) is grounded,
the ABS-ECU (terminal 14) will go into diagnostic
mode.

TECHNICAL DESCRIPTION (COMMENT)
When communication with the scan tool is not
possible, the cause is probably an open circuit in the
ABS-ECU power circuit or an open circuit in the
diagnostic output circuit.

TROUBLESHOOTING HINTS (The most likely
causes for this case:)

•

Blown fuse

•

Damaged wiring harness and connector

•

Malfunction of the hydraulic unit (Integrated with
ABS-ECU)

DIAGNOSIS

Required Special Tool:

•

MB991223: Harness Set

AC003695 AB

CONNECTOR: A-03

AC003131 AB

CONNECTOR: C-12

AC003089 AB

CONNECTOR: C-23

AC003089AE

CONNECTOR: C-57

AC003082AK

CONNECTORS: C-73, C-77

C-73

JUNCTION BLOCK
(FRONT VIEW)

C-77

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-24

STEP 1. Check the power supply circuit at ABS-ECU
connector A-03.
(1) Disconnect connector A-03 and measure at the harness

side.

(2) Start the engine.
(3) Measure the voltage between terminal 4 and ground.

Q: Is voltage approximately 12 volts?

YES : Go to Step 3.
NO : Go to Step 2.

STEP 2. Check the harness wire between ignition switch
(IG2) and ABS-ECU connector A-03
NOTE: After inspecting intermediate connector C-12, C-73, or
C-77, inspect the wire. If intermediate connector C-12, C-73, or
C-77 is damaged, repair or replace it. Refer to GROUP 00E,
Harness Connector Inspection

P.00E-2

. If the connector has

been repaired or replaced, go to Step 3 .

Q: Is any harness wire between ignition switch (IG2) and

ABS-ECU connector A-03 damaged?
YES : Repair them and go to Step 5.
NO : Go to Step 3.

AC003703 AB

A-03 (HARNESS SIDE)

AC003695 AB

CONNECTOR: A-03

AC003131 AB

CONNECTOR: C-12

AC003082AK

CONNECTORS: C-73, C-77

C-73

JUNCTION BLOCK
(FRONT VIEW)

C-77