Mitsubishi 380. Manual — part 786

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-68

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-69

STEP 3. 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 B1411 set?

YES : Go to Step 4.
NO : Replace the passenger's air bag module (Refer to

P.52B-237

). Then go to Step 5.

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

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-70

STEP 4. Check the harness for open circuit between
SRS-ECU connector C-121 (terminal No.37 and 36) and the
passenger's air bag module connector C-110 (terminal
No.1 and 2).
(1) Unclip passenger’s air bag module connector C-110.

(2) Disconnect SRS-ECU connector C-121 and passenger's air

bag module connector C-110.

CAUTION

Do not insert a test probe into the terminal from its front
side directly as the connector contact pressure may be
weakened.
(3) Check for continuity between the following terminals. It

should be less than 2 ohms.

• SRS-ECU connector C-121 (terminal No.37) and the

passenger’s air bag module connector C-110 (terminal
No.1)

• SRS-ECU connector C-121 (terminal No.36) and the

passenger’s air bag module connector C-110 (terminal
No.2)

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)

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-71

Q: Does continuity exist?

YES : Erase the diagnostic trouble code memory, and check

the diagnostic trouble code. If DTC B1411 set, replace
the SRS-ECU (Refer to

P.52B-234

). Then go to Step

5.

NO : Replace the harness wires between SRS-ECU

connector C-121 and passenger’s air bag module
connector C-110. Then go to Step 5.

STEP 5. 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 DTC B1411 set?

YES : Return to Step 1.
NO : The procedure is complete.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827