Mitsubishi Galant (2004+). Manual - part 429

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-327

STEP 15. Check the A/C-ECU for short circuit. Measure the 
resistance at A/C-ECU connector C-10 <manual air 
conditioning system (low)> or C-15 <manual air 
conditioning system (middle) or automatic air conditioning 

system>.

CAUTION

A digital multimeter should be used. For details refer to 

P.54C-4

.

(1) Disconnect A/C-ECU connector C-10 <manual air 

conditioning system (low)> or C-15 <manual air 
conditioning system (middle) or automatic air conditioning 
system>, and measure the resistance at the component 
side of A/C-ECU connector C-10 <manual air conditioning 
system (low)> or C-15 <manual air conditioning system 
(middle) or automatic air conditioning system>.

(2) Measure the resistance between A/C-ECU connector 

terminals 5 and 6 <manual air conditioning system (low)> or 
terminals 14 and 15 <manual air conditioning system 
(middle) or automatic air conditioning system>.

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-465

.

NO :  If the resistance measures less than 1 k

Ω, replace the 

A/C-ECU.

AC305234AB

C-10 HARNESS SIDE

C-15 HARNESS SIDE

CONNECTORS: C-10, C-15

C-10 (B)

C-15 (B)

AC209438

AC209438

COMPONENT SIDE: C-10

AT

TEST 
HARNESS

AC209438

AC209438

COMPONENT SIDE: C-15

AY

TEST 
HARNESS

TEST 
HARNESS

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-328

STEP 16. Check the CAN_L and H lines (communication 
lines including the SRS-ECU) between joint connector (3) 
and the SRS-ECU for a short circuit. Measure the 

resistance at joint connector (3) C-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 joint connector (3) C-02, and measure the 

resistance at the wiring harness side of joint connector (3) 
C-02.

(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.

(4) Measure the resistance between joint connector (3) 

terminals 3 and 14.

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, go to Step 

23  .

NO :  If the resistance measures less than 1 k

Ω, go to Step 

17.

STEP 17. Check intermediate connector C-22 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: Is intermediate connector C-22 in good condition?

YES : Go to Step 18.
NO :  Repair the damaged parts.

AC305231AP

CONNECTOR: C-02

AC209438

11

22

10

21

9

20

8

19

7

18

6

17

5

16

4

15

3

14

2

13

1

12

TEST 
HARNESS

AV

TEST 
HARNESS

HARNESS SIDE: C-02

AC305233 AI

CONNECTOR: C-22

C-22 (Y)

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-329

STEP 18. Check the lines between the CAN_L and H lines 
(communication line including ECUs) of the floor wiring 
harness for a short circuit. Measure the resistance at 

intermediate connector C-22.

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 intermediate connector C-22, and measure the 

resistance at the male side (at floor wiring harness side).

(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.

(4) Measure the resistance between intermediate connector 

terminals 22 and 23.

OK: 120 

± 20 Ω

Q: Does the resistance measure 120 

± 20 Ω?

YES : If the resistance measures 120 

± 20 Ω, go to Step 22.

NO :  If the resistance does not measure 120 

± 20 Ω> Go to 

Step 19.

AC305233 AI

CONNECTOR: C-22

C-22 (Y)

AC204582

AC204582CS

MALE SIDE: C-22

TEST 
HARNESS

TEST HARNESS

DIAGNOSIS

TSB Revision

CONTROLLER AREA NETWORK (CAN)

54C-330

STEP 19. Check the CAN_L and H lines (communication 
lines only) between the SRS-ECU connector and the 
intermediate connector for a short circuit. Measure the 

resistance at intermediate connector C-22.

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 intermediate connector C-22 and SRS-ECU 

connector C-121, and measure the resistance at the male 
side of intermediate connector C-22 (at floor wiring harness 
side).

(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.

AC305234AC

CONNECTORS: C-22, C-121

C-121 HARNESS SIDE

C-121 (Y)

C-22 (Y)

C-22

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