Mitsubishi 380. Manual - part 784

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-60

STEP 1. Using diagnostic tool MB991958, diagnose the 
CAN bus line.

CAUTION

To prevent damage to diagnostic tool MB991958, always 
turn the ignition switch to the "LOCK" (OFF) position 
before connecting or disconnecting diagnostic tool 
MB991958.
(1) Connect diagnostic tool MB991958. Refer to "How to 

connect the diagnostic tool 

P.52B-19

."

(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.
(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the CAN bus line found to be normal?

YES : Go to Step 2.
NO :  Repair the CAN bus line (Refer to GROUP 54C, 

Diagnosis ).

STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.

Q: Is the DTC set?

YES : Go to Step 3.
NO :  There is an intermittent malfunction such as poor 

engaged connector(s) or open circuit (Refer to 
GROUP 00, How to Use Troubleshooting/Inspection 
Service Points 

− How to Cope with Intermittent 

Malfunctions ).

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-61

STEP 3. Using diagnostic tool MB991958, read the 
diagnostic trouble code.

CAUTION

To prevent damage to diagnostic tool MB991958, always 
turn the ignition switch to the "LOCK" (OFF) position 
before connecting or disconnecting diagnostic tool 
MB991958.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the DTC is set.
(3) Turn the ignition switch to the "LOOK (OFF)" position.

Q: Is DTC B1519 set?

YES : Go to Step 4.
NO :  Go to Step 5.

STEP 4. Check SRS-ECU connector C-121.
Q: Is the connector correctly engaged?

YES : Go to Step 5.
NO :  Engage the connector correctly. Then go to Step 9.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

24DB062A

CONNECTOR: C-121

C-121 (Y)

SRS-ECU

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

INSTRUMENT

HARNESS

CONNECTOR

(REAR VIEW)

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-62

STEP 5. Check SRS-ECU connector C-121 and passenger’s 
air bag module connector C-110. (Using diagnostic 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  set?

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

B1410  set as connector C-121 or C-110 was 
engaged improperly.

52DB018A

C-110 (Y)

FRONT DECK
CROSSMEMBER

CONNECTOR: C-110

HARNESS SIDE 
CONNECTOR
(REAR VIEW)

24DB062A

CONNECTOR: C-121

C-121 (Y)

SRS-ECU

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

INSTRUMENT

HARNESS

CONNECTOR

(REAR VIEW)

AC306561AD

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

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-63

STEP 6. Check the passenger's air bag module. (Using 
diagnostic 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 ) by testprobe.

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

diagnostic trouble code.

Q: Is DTC B1410 ?

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

P.52B-237

). Then go to Step 9. 

52DB018A

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