Mitsubishi Galant 9G. Manual — part 1287

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-252

STEP 48. Check the CAN_L line (communication line only)
between the powertrain control module connector and
ABS-ECU connector for short to ground. Measure the
resistance at powertrain control module connector B-19.

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 powertrain control module connector B-19 and

ABS-ECU connector A-02, and measure the resistance at
the harness side of powertrain control module connector
B-19.

(2) Turn the ignition switch to the "LOCK" (OFF) position.

CAUTION

Disconnect the negative battery terminal. For details refer
to

P.54C-4

.

(3) Disconnect the negative battery terminal.

AC305206

CONNECTOR: A-02

AG

A-02 (GR)

HARNESS SIDE

AC306248AD

B-19 (B)

CONNECTOR: B-19

PCM

AIR
CLEANER

HARNESS SIDE

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-253

(4) Measure the resistance between powertrain control module

connector terminal 18 and body ground.

OK: 1 k

Ω or more

CAUTION

Strictly observe the specified wiring harness repair proce-
dure. For details refer to

P.54C-5

.

Q: Does the resistance measure 1 k

Ω or more?

YES : If the resistance measures 1 k

Ω or more, go to Step

49 .

NO : If the resistance measures less than 1 k

Ω, repair the

wiring harness between powertrain control module
connector and ABS-ECU connector.

STEP 49. Check the CAN_L line inside the ABS-ECU for
short to ground. Measure the resistance at ABS-ECU
connector A-02.

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.

AC209364IP

HARNESS SIDE: B-19

TEST HARNESS

AC305206

CONNECTOR: A-02

AG

A-02 (GR)

HARNESS SIDE

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-254

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

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

(3) Turn the ignition switch to the "LOCK" (OFF) position.

CAUTION

Disconnect the negative battery terminal. For details refer
to

P.54C-4

.

(4) Disconnect the negative battery terminal.
(5) Measure the resistance between special tool MB991970

(ABS check harness) connector terminal 7 and body
ground.

OK: 1 k

Ω or more

Q: Does the resistance measure 1 k

Ω or more?

YES : If the resistance measures 1 k

Ω or more, diagnose

CAN bus lines thoroughly by referring to

P.54C-486

.

NO : If the resistance measures less than 1 k

Ω, replace the

ABS-ECU.

AC209767

TEST
HARNESS

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

SPECIAL TOOL
MB991970

ABS-
ECU

SPECIAL TOOL MB991970
CONNECTOR

AD

MEASUREMENT CONNECTOR

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-255

DIAGNOSTIC ITEM 6: Diagnose shorts in the ground to CAN bus line <Vehicles with ABS and vehicles
with 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 so, a component con-
nected 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

ABS-ECU

MULTI CENTER
DISPLAY UNIT