Mitsubishi Galant. Manual — part 526

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-37

STEP 6. Check the harness wire between combination
meter connector C-30 and ABS warning light relay
connector A-10X.
(1) Remove the combination meter. (Refer to GROUP 54A,

Combination Meter

P.54A-65

.)

(2) Check the harness wire between combination meter of

connector C-30 terminal 8 and ABS warning light relay
connector A-10X terminal 5.

Q: Are any harness wire between the combination meter

connector A-30 and ABS warning light relay connector
A-10X damage?
YES : Replace the ABS-ECU then go to Step 7.
NO : Repair the harness wire and then go to Step 7.

STEP 7. Check symptoms

Q: Does the ABS warning light remain illuminated after the

engine is started?
YES : Return to Step 1.
NO : This diagnosis is complete.

INSPECTION PROCEDURE 4 , Faulty ABS operation

TECHNICAL DESCRIPTION (COMMENT)
The cause depends on driving and road surface
conditions, so diagnosis may be difficult. However, if
no diagnostic trouble code is displayed, carry out the
following inspection.

TROUBLESHOOTING HINTS
The most likely cause for this case:

•

Malfunction of the hydraulic unit

DIAGNOSIS

Check the hydraulic unit.

•

Refer to

P.35B-43

. If the hydraulic unit (integrated with

ABS-ECU) is malfunctioning, replace it. Then check that the
malfunction symptom is eliminated.

DATA LIST REFERENCE TABLE

M1352011500070

The following items can be read by the scan tool
from the ABS-ECU input data.

AC003919

CONNECTOR: C-30

AB

AC003923 AB

CONNECTOR: A-10X

RELAY BOX IN

ENGINE

COMPARTMENT

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-38

ACTUATOR TEST REFERENCE TABLE

M1352011600055

The scan tool activates the following actuators for
testing.

NOTE: If the ABS-ECU is inoperative, actuator
testing cannot be carried out.

NOTE: Actuator testing is only possible when the
vehicle is stationary. If the vehicle speed during
actuator testing exceeds 10 km/h (6 mph), forced
actuation will be canceled.

ACTUATOR TEST SPECIFICATIONS

CHECK AT ABS-ECU

M1352011800071

TERMINAL VOLTAGE CHECK CHART
1. Measure the voltages between terminals (8) and

(24) (ground terminals) and each respective
terminal.

2. The terminal layouts are shown in the illustrations

below.

MUT-II SCAN
TOOL DISPLAY

ITEM NO.

CHECK ITEM

CHECKING
REQUIREMENTS

NORMAL VALUE

ECU VOLTAGE

16

ABS-ECU power supply
voltage

Ignition switch power
supply voltage and valve
monitor voltage

9

−

16 V

FR SNSR

11

Front-right wheel speed
sensor

Drive the vehicle

Vehicle speeds
displayed on the
speedometer and
scan tool are
identical.

FL SNSR

12

Front-left wheel speed
sensor

RR SLSR

13

Rear-right wheel speed
sensor

RL SNSR

14

Rear-left wheel speed
sensor

STOPLIGHT SW 36

Stoplight switch

Depress the brake pedal. ON

Release the brake pedal. OFF

NO.

ITEM

PARTS TO BE
ACTIVATED

01Solenoid valve for

front-left wheel

Solenoid valves and
pump motors in the
hydraulic unit (simple
inspection mode)

02

Solenoid valve for
front-right wheel

03

Solenoid valve for
rear-left wheel

04

Solenoid valve for
rear-right wheel

AC000971AC

ACTIVATION PATTERN

A

B

C

SOLENOID
VALVE

END OF
FORCED
ACTION

START OF
FORCED
ACTION

1 s

2 s

PUMP
MOTOR

ON

OFF

NOTE
A:
B:
C:

HYDRAULIC PRESSURE DECREASES
HYDRAULIC PRESSURE HOLDS
HYDRAULIC PRESSURE INCREASES

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-39

NOTE: Do not measure terminal voltage for
approximately three seconds after the ignition switch
is turned "ON." The ABS-ECU performs the initial
check during that period.

RESISTANCE AND CONTINUITY BETWEEN
HARNESS-SIDE CONNECTOR TERMINALS
1. Turn the ignition switch to the "LOCK" (OFF)

position and disconnect the ABS-ECU connectors
before checking resistance and continuity.

2. Check between the terminals indicated in the

table below.

3. The terminal layouts are shown in the illustration

below.

AC003648

CONNECTOR
TERMINAL
NO.

SIGNAL

CHECKING REQUIREMENT

NORMAL
CONDITION

4

ABS-ECU
power supply

Ignition switch: "ON"

Battery positive
voltage

Ignition switch: "START"

Approximately 0 V

7

Scan tool

Connect the scan tool

Serial communica-
tion with scan tool

Do not connect the scan tool

1 V or less

9

Solenoid valve
power supply

Always

Battery positive
voltage

14

Input from
diagnostic
indication selection

Connect the scan tool

Approximately 0 V

Do not connect the scan tool

Approximately 12 V

16

Output to ABS
warning light
relay control

Ignition switch:
"ON"

The light is switch off.

1 V or less

The light is illuminated.

Battery positive
voltage

18

Input from stoplight
switch

Stoplight switch: "ON"

Battery positive
voltage

Stoplight switch: "OFF"

Approximately 0 V

25

Motor power sup-
ply

Always

Battery positive
voltage

ANTI-SKID BRAKING SYSTEM (ABS) DIAGNOSIS

TSB Revision

ANTI-LOCK BRAKING SYSTEM(ABS)

35B-40

AC003647

CONNECTOR
TERMINAL NO.

SIGNAL

NORMAL CONDITION

1

−

2

Front-left wheel speed sensor

1.28

−

1.92 k

Ω

22

−

23

Rear-right wheel speed sensor

1.28

−

1.92 k

Ω

19

−

20

Front-right wheel speed sensor

1.28

−

1.92 k

Ω

5

−

6

Rear-left wheel speed sensor

1.28

−

1.92 k

Ω

8

−

body ground

Solenoid valve ground

Continuity

24

−

body ground

Motor ground

Continuity