Mitsubishi Galant (2004+). Manual - part 390

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-171

STEP 55. Check the CAN_L line inside the ABS-ECU for a 
short to the power supply. Measure the voltage at 
ABS-ECU connector A-02 for loose, corroded or damaged 

terminals, or terminals pushed back in the connector.

CAUTION

A digital multimeter should be used. For details refer to 

P.54C-4

.

CAUTION

The test wiring harness should be used. For details refer to 

P.54C-4

.

(1) Disconnect ABS-ECU connector A-02.

(2) Connect special tool MB991970 (ABS check harness) to 

the ABS-ECU and the wiring harness, and measure the 
voltage at special tool MB991970 (ABS check harness).

(3) Turn the ignition switch to the "ON" position.
(4) Measure the voltage between special tool MB991970 (ABS 

check harness) connector terminal 7 and body ground.

OK: 4.0 V or less

Q: Does the voltage measure 4.0 V or less?

YES : If the voltage measures 4.0 V or less, diagnose CAN 

bus lines thoroughly by referring to 

P.54C-534

.

NO :  If the voltage measures more than 4.0 V, replace the 

ABS-ECU.

AC305206

CONNECTOR: A-02

AG

A-02 (GR)

HARNESS SIDE

AC209767

2

19

1

18

25

8

15

16

17

27

28

26

11

9

10

12

13

14

23

24

22 21

7 6

5

4

20

3

TEST 
HARNESS

SPECIAL TOOL
MB991970

ABS-
ECU

AB

MEASURE AT THIS CONNECTOR

SPECIAL TOOL MB991970 
CONNECTOR

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-172

DIAGNOSTIC ITEM 4: Diagnose shorts in the ground to CAN bus line <Vehicles without ABS and 
vehicles without multi-center display (middle-grade type)>

CAUTION

When servicing a CAN bus line, ground yourself 
by touching a metal object such as an unpainted 
water pipe. If you fail to do this, a component 
connected to the CAN bus line may be damaged.

DATA LINK
CONNECTOR

ETACS-ECU

POWERTRAIN
CONTROL MODULE

JOINT
CONNECTOR (3)

COMBINATION
METER

A/C-ECU

SRS-ECU

NOTE

: MANUAL AIR CONDITIONING SYSTEM <LOW>
: MANUAL AIR CONDITIONING SYSTEM <MIDDLE>
  OR AUTOMATIC AIR CONDITIONING SYSTEM

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-173

.

TROUBLE JUDGMENT
A short to ground may be present when the voltage 
between the CAN bus line (CAN_L or CAN_H) and 
body ground is less than 1.0 V. In this condition, an 
abnormal voltage may be measured at CAN_L and 
CAN_H lines.

.

COMMENTS ON TROUBLE SYMPTOM
The wiring harness wire or connectors may have 
loose, corroded, or damage terminals, or terminals 
pushed back in the connector, or a ECU may be 
defective.

.

TROUBLESHOOTING HINTS

• The wiring harness or connectors may have 

loose, corroded, or damaged terminals, or termi-
nals pushed back in the connector

• the ETACS-ECU may be defective

• The combination meter may be defective

• The A/C-ECU may be defective

• The SRS-ECU may be defective

• The powertrain control module may be defective

DIAGNOSIS

Required Special Tool:

• MB991223: Harness Set

AC306248AB

B-19 (B)

CONNECTOR: B-19

AIR
CLEANER

PCM

AC305231BZ

C-101

C-125 (B)

C-29

C-02

CONNECTORS: C-02, C-29, C-101, C-125

AC305233 AU

CONNECTORS: C-10, C-15, C-22, C-121

C-121 (Y)

C-22 (Y)

C-10 (B)

C-15 (B)

AC305413

C-218 (GR)

CONNECTOR: C-218

AJ

JUNCTION BLOCK
(REAR VIEW)

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-174

STEP 1. Check powertrain control module connector B-19, 
combination meter connector C-101 and data link 
connector C-125 for loose, corroded or damaged 
terminals, or terminals pushed back in the connector.

CAUTION

The strand end of the twisted wire should be within 10 cm 
(4 inches) from the connector. For details refer to 

P.54C-4

.

Q: Are powertrain control module connector B-19, 

combination meter connector C-101 and data link 
connector C-125 in good condition?
YES : Go to Step 2.
NO :  Repair the damaged parts.

AC306248AD

B-19 (B)

CONNECTOR: B-19

PCM

AIR
CLEANER

HARNESS SIDE

AC305232

CONNECTORS: C-101, C-125

AH

C-101

C-125

C-125 (B)

C-101 HARNESS SIDE