Mitsubishi Galant (2004+). Manual - part 1587

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-241

STEP 5. Check the harness for open circuit between 
SRS-ECU connector C-121 (terminal No.23 <DTC B1476> 
or terminal No.24 <DTC B1477>) and the ignition switch 
connector C-308 (terminal No.2).

AC305362

CONNECTOR: C-121

C-121 (Y)

AH

SRS-ECU

C-121
HARNESS SIDE 
CONNECTOR
(REAR VIEW)

42

31

38

27

21

41

28

39

22

30

25

47

36

33

44

34

45

37

48

26

29

23

40

32

43

35

46

24

B

A

AC305235AG

CONNECTOR: C-308

C-308

2
5

4

1

6

3

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-242

NOTE: After inspecting intermediate connectors C-22, C-211 
and C-215, inspect the wiring harness. If intermediate connec-
tors are damaged, repair or replace them. Refer to GROUP 
00E, Harness Connector Inspection 

P.00E-2

. Then go to Step 

10.
Q: Is the harness wire between SRS-ECU connector C-121 

(terminal No.23 <DTC B1476> or terminal No.24 <DTC 
B1477>) and the ignition switch connector C-308 
(terminal No.2) in good condition?
YES : Go to Step 10.
NO :  Replace the harness wire between SRS-ECU 

connector C-121 and the ignition switch connector 
C-308. Then go to Step 10.

STEP 6. Check a burned-out fuse.
(1) Replace the fuse.
(2) Turn the ignition switch to the "ON" position, wait for at least 

one minute and then turn the ignition switch to the "LOCK" 
(OFF) position. 

(3) Check the fuse.
Q: Is the fuse in good condition?

YES : Go to Step 10.
NO :  It is possible that the circuit using fuse No22 <B1476> 

or No.23 <B1477> is shorted, go to Step 7.

AC305233 AI

CONNECTOR: C-22

C-22 (Y)

AC305416

CONNECTORS: C-211, C-215

JUNCTION BLOCK 
(FRONT VIEW)

C-215

C-211

HARNESS SIDE

C-211

HARNESS SIDE

C-215

AK

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-243

STEP 7. Check the SRS-ECU power supply circuit for short 
circuit to ground. Measure the resistance at the junction 
block connector C-211.

(1) Disconnect junction block connector C-211, and measure at 

the wiring harness side.

CAUTION

Do not insert a test probe into the terminal from its front 
side directly, as the connector contact pressure may be 
weakened.
(2) Check for continuity between terminal 7 <DTC B1476> or 

24 <DTC B1477> and body ground.
It should be open circuit.

Q: Does continuity exist?

YES : Check the other circuit, which flows through fuse 

No.22 <DTC B1476> or fuse No.23 <DTC 
B1477>.Then go to Step 10.

NO :  Go to Step 8.

STEP 8. Check the power supply circuit for short circuit to 
ground. Measure the resistance at the SRS-ECU connector 
C-121.

(1) Disconnect SRS-ECU connector C-121, and measure at 

the wiring harness side.

CAUTION

Do not insert a test probe into the terminal from its front 
side directly as the connector contact pressure may be 
weakened.
(2) Check for continuity between terminal 23 <DTC B1476> or 

24 <DTC B1477> and body ground.

It should be open circuit.

Q: Does continuity exist?

YES : Erase the diagnostic trouble code memory, and check 

the diagnostic trouble code. If DTC B1476 or B1477 
sets, replace the SRS-ECU. (Refer to 

P.52B-365

). 

Then go to Step 10.

NO :  Go to Step 9.

AC305415AN

CONNECTOR: C-211

AC308200

1 2 3 4 5 6 7 8 9 10 1112 1314

1516 1718 19 20 212223 242526 2728

C-211 HARNESS SIDE
CONNECTOR (REAR VIEW)

AB

AC305362

CONNECTOR: C-121

C-121 (Y)

AH

SRS-ECU

C-121
HARNESS SIDE 
CONNECTOR
(REAR VIEW)

42

31

38

27

21

41

28

39

22

30

25

47

36

33

44

34

45

37

48

26

29

23

40

32

43

35

46

24

B

A

AC308195

42

31

38

27

21

41

28

39

22

30

25

47

36

33

44

34

45

37

48

26

29

23

40

32

43

35

46

24

B

A

C-121 HARNESS SIDE
CONNECTOR (REAR VIEW)

AB

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-244

STEP 9. Check the harness for short circuit to ground 
between SRS-ECU connector C-121 (terminal No.23 <DTC 
B1476> or terminal No.24 <DTC B1477>) and junction 
block connector C-211 (terminal No.7 <DTC B1476> or 
terminal No.24 <DTC B1477> ).

NOTE: After inspecting intermediate connector C-22, inspect 
the wiring harness. If intermediate connectors are damaged, 
repair or replace them. Refer to GROUP 00E, Harness Con-
nector Inspection 

P.00E-2

. Then go to Step 10.

Q: Is the harness wire between SRS-ECU connector C-121 

(terminal No.23 <DTC B1476> or terminal No.24 <DTC 
B1477>) and junction block connector C-211 (terminal 
No.7 <DTC B1476> or 24 <DTC B1477>) in good 
condition?
YES : Go to Step 10.
NO :  Replace the harness wire between SRS-ECU 

connector C-121 and junction block connector C-211. 
Then go to Step 10.

AC305362

CONNECTOR: C-121

C-121 (Y)

AH

SRS-ECU

C-121
HARNESS SIDE 
CONNECTOR
(REAR VIEW)

42

31

38

27

21

41

28

39

22

30

25

47

36

33

44

34

45

37

48

26

29

23

40

32

43

35

46

24

B

A

AC305415AH

CONNECTOR: C-211

C-211

HARNESS SIDE

JUNCTION BLOCK

(FRONT VIEW)

AC305233 AI

CONNECTOR: C-22

C-22 (Y)