Mitsubishi Galant (2004+). Manual - part 1594

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-269

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

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan 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 B1540, B1541, B1542, B1543, B1545 or B1546 

set?
YES : Carry out the troubleshooting of the occupant 

classification-ECU or the occupant classification 
sensor system.  (Refer to 

P.52B-318

 <B1540, B1541, 

B1542, B1543>, 

P.52B-320

 <B1545, B1546>). 

NO :  Go to Step 4 .

STEP 4. Check the passenger’s air bag OFF indicator light 
connector C-06.

Q: Is the connector correctly engaged?

YES : Go to Step 5 .
NO :  Engage the connector correctly. Then go to Step 10 .

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

AC305233CX

CONNECTOR: C-06

HARNESS SIDE

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-270

STEP 5. Measure the voltage at passenger’s air bag OFF 
indicator light connector C-06.

(1) Disconnect passenger’s air bag OFF indicator light 

connector C-06.

(2) Measure the voltage between C-06 harness side connector 

terminal 1 and body ground.
Voltage should measure approximately 12 volt.

Q: Is the check result satisfactory?

YES : Go to Step 7 .
NO :  Go to Step 6 .

STEP 6. Check the harness for short circuit between 
ignition switch connector C-308 (terminal No.2) and 

passenger’s air bag OFF indicator light C-06 (terminal 
No.1).

AC305233CX

CONNECTOR: C-06

HARNESS SIDE

AC308205

C-06 HARNESS SIDE
CONNECTOR

AB

AC305235AG

CONNECTOR: C-308

C-308

2
5

4

1

6

3

AC305233CX

CONNECTOR: C-06

HARNESS SIDE

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-271

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

P.00E-2

. Then 

go to Step 10  .
Q: Are the harness wires between Ppassenger’s air bag 

OFF indicator light connector C-06 (terminal No.1) and 
the ignition switch connector C-308 (terminal No.2) in 
good condition?
YES : Go to Step 7 .
NO :  Repair the harness wires. Then go to Step 10 .

STEP 7. Check SRS-ECU connector C-121.

Q: Is the connector correctly engaged?

YES : Go to Step 8 .
NO :  Engage the connector correctly. Then go to Step 10 .

AC305416

CONNECTORS: C-211, C-215

JUNCTION BLOCK 
(FRONT VIEW)

C-215

C-211

HARNESS SIDE

C-211

HARNESS SIDE

C-215

AK

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

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-272

STEP 8. Check the harness for short circuit between 
passenger’s air bag OFF indicator light C-06 (terminal 
No.3) and SRS-ECU connector C-121 (terminal No.21).

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

P.00E-2

. Then go to Step 10  .

Q: Are the harness wires between SRS-ECU connector 

C-121 (terminal No.21) and the passenger’s air bag OFF 
indicator light C-06 (terminal No.3) in good condition?
YES : Go to Step 9 .
NO :  Repair the harness wires. Then go to Step 10 .

AC305233CX

CONNECTOR: C-06

HARNESS SIDE

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

AC305233 AI

CONNECTOR: C-22

C-22 (Y)