Mitsubishi Galant 9G. Manual — part 1419

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-86

STEP 5. Check SRS-ECU connector C-121 and passenger’s
air bag module connector C-110. (Using scan tool
MB991958, read the diagnostic trouble code.)
(1) Disconnect the negative battery terminal.
(2) Disconnect connectors C-121 and C-110, and then

reconnect them.

(3) Slide the outer housing of the clock spring side of driver’s

air bag module connector C-110 in the arrow direction
shown, and disconnect the connector.

(4) Connect the negative battery terminal.
(5) Erase the diagnostic trouble code memory, and check the

diagnostic trouble code.

Q: Is DTC B1410 <1st squib> or B1490 <2nd squib> set?

YES : Go to Step 6.
NO : The procedure is complete. It is assumed that DTC

B1410 <1st squib> or B1490 <2nd squib> set as
connector C-121 or C-110 was engaged improperly.

AC307137AC

C-110 (Y)

FRONT DECK
CROSSMEMBER

CONNECTOR: C-110

HARNESS SIDE
CONNECTOR
(REAR VIEW)

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

AC306561AD

OUTER HOUSING OF THE PASSENGER'S
AIR BAG MODULE CONNECTOR C-110

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-87

STEP 6. Check the passenger's air bag module. (Using
scan tool MB991958, read the diagnostic trouble code.)
(1) Disconnect the negative battery terminal.
(2) Disconnect the passenger’s air bag module connector

C-110.

(3) Slide the outer housing of the clock spring side of

passenger’s air bag module connector C-110 in the arrow
direction shown, and disconnect the connector.

(4) Connect special tool MB991865 to special tool MB991866.

CAUTION

Do not insert a test probe into the terminal from its front
side directly as the connector contact pressure may be
weakened.
(5) Insert special tool MB991866 into the harness side

connector C-110 (terminal No.1 and 2 <1st squib> or
terminal No.3 and 4 <2nd squib>) by backprobing.

(6) Connect the negative battery terminal.
(7) Erase the diagnostic trouble code memory, and check the

diagnostic trouble code.

Q: Is DTC B1410 <1st squib> or B1490 <2nd squib> set?

YES : Go to Step 7.
NO : Replace the passenger's air bag module (Refer to

P.52B-368

). Then go to Step 9.

AC307137AC

C-110 (Y)

FRONT DECK
CROSSMEMBER

CONNECTOR: C-110

HARNESS SIDE
CONNECTOR
(REAR VIEW)

AC306561AD

OUTER HOUSING OF THE PASSENGER'S
AIR BAG MODULE CONNECTOR C-110

AC306760AB

MB991865 (DUMMY
RESISTOR: 3

Ω

)

MB991866
(RESISTOR HARNESS)

C-110 HARNESS
CONNECTOR

C-110
PASSENGER'S
AIR BAG MODULE
CONNECTOR

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-88

STEP 7. Check the passenger’s air bag module circuit at
SRS-ECU connector C-121.
(1) Disconnect SRS-ECU connector C-121.

DANGER

To prevent the air bag from deploying unintentionally,
disconnect the passenger’s air bag module connec-
tor C-110 to short the squib circuit.

(2) Disconnect the passenger's air bag module connector

C-110.

(3) Slide the outer housing of the clock spring side of driver’s

air bag module connector C-110 in the arrow direction
shown, and disconnect the connector.

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

AC307137AC

C-110 (Y)

FRONT DECK
CROSSMEMBER

CONNECTOR: C-110

HARNESS SIDE
CONNECTOR
(REAR VIEW)

AC306561AD

OUTER HOUSING OF THE PASSENGER'S
AIR BAG MODULE CONNECTOR C-110

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-89

CAUTION

Insert an insulator such as a cable tie to a depth of 4mm
(0.16 inch) or more, otherwise the short spring will not be
released.
(4) Insert a cable tie [3 mm (0.12 inch) wide, 0.5 mm (0.02 inch)

thick] between terminals 27 and 28 <1st squib> or 30 and
31 <2nd squib>, and the short spring to release the short
spring.

CAUTION

Do not insert a test probe into the terminal from its front
side directly as the connector contact pressure may be
weakened.
(5) Check for continuity between C-121 harness side connector

terminals 27 and 28 <1st squib> or 30 and 31 <2nd squib>.
It should be open circuit.

Q: Does continuity exist?

YES : Go to Step 8.
NO : Erase the diagnostic trouble code memory, and check

the diagnostic trouble code. If DTC B1410 <1st
squib> or B1490 <2nd squib> set, replace the
SRS-ECU (Refer to

P.52B-365

). Then go to Step 9.

AC308142

SECTION
A - A

C-121 HARNESS SIDE
CONNECTOR
(FRONT VIEW)

CABLE TIE

SHORT SPRING

4 mm OR MORE

TERMINAL

AB

<1ST SQUIB>

A

A

AC308143

SECTION
A - A

C-121 HARNESS SIDE
CONNECTOR
(FRONT VIEW)

CABLE TIE

SHORT SPRING

4 mm OR MORE

TERMINAL

AB

<2ND SQUIB>

A

A

AC301582

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)

<1ST SQUIB>

AC

AC308150

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)

<2ND SQUIB>

AB