Mitsubishi Galant 9G. Manual — part 1449

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-206

STEP 4. Check the passenger's seat belt pre-tensioner
circuit. Measure the resistance at the SRS-ECU connector
C-120.
(1) Disconnect SRS-ECU connector C-120.

(2) Disconnect passenger's seat belt pre-tensioner connector

D-33. Use a flat-tipped screwdriver to unlock the locking
button at the harness side connector by withdrawing it
toward you in two stages, and then disconnect the
connector.

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 C-120 harness side connector

terminals 59, 60 and body ground.
It should be open circuit.

Q: Does continuity exist?

YES : Go to Step 5.
NO : Erase the diagnostic trouble code memory, and check

the diagnostic trouble code. If DTC B1463 sets,
replace the SRS-ECU (Refer to

P.52B-365

). Then go

to Step 6.

AC305362

CONNECTOR: C-120

C-120 (Y)

AG

SRS-ECU

63

55

51

69

61

66

58

65

64

56 57

68

60

67

59

70

62

53

52 B

A

54

C-120
Harness side
connector
(rear view)

AC307915 AC

CONNECTOR: D-33

D-33 (B)

FORWARD

CENTER
PILLAR

HARNESS SIDE
CONNECTOR
(FRONT VIEW)

2 1

AC103556AU

LOCKING BUTTON

FLAT-TIP SCREW
DRIVER

D-33 HARNESS
SIDE CONNECTOR

D-33 PASSENGER'S
SEAT BELT
PRE-TENSIONER
CONNECTOR

AC301574

63

55

51

69

61

66

58

65

64

56 57

68

60

67

59

70

62

53

52 B

A

54

C-120 HARNESS SIDE
CONNECTOR (REAR VIEW)

AD

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-207

STEP 5. Check harness wires for short circuit to ground
between SRS-ECU connector C-120 (terminal No.59 and
60) and passenger's seat belt pre-tensioner connector
D-33 (terminal No.1 and 2).
Q: Are the harness wires between SRS-ECU connector

C-120 (terminal No.59 and 60) and passenger's seat belt
pre-tensioner connector D-33 (terminal No.1 and 2) in
good condition?
YES : Go to Step 6.
NO : Replace the harness wires between SRS-ECU

connector C-120 and passenger's seat belt
pre-tensioner connector D-33. Then go to Step 6.

STEP 6. 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 B1463 set?

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

AC305362

CONNECTOR: C-120

C-120 (Y)

AG

SRS-ECU

63

55

51

69

61

66

58

65

64

56 57

68

60

67

59

70

62

53

52 B

A

54

C-120
Harness side
connector
(rear view)

AC307915 AC

CONNECTOR: D-33

D-33 (B)

FORWARD

CENTER
PILLAR

HARNESS SIDE
CONNECTOR
(FRONT VIEW)

2 1

AC305412

AB

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-208

DTC B1404: Driver's Air Bag Module (1st Squib Ignition Drive Circuit) System Detected Short Circuit
DTC B1405: Driver's Air Bag Module (1st Squib Ignition Drive Circuit) System Detected Open Circuit
DTC B1414: Passenger’s (Front) Air Bag Module (1st Squib Ignition Drive Circuit) System Detected
Short Circuit DTC B1415: Passenger’s (Front) Air Bag Module (1st Squib Ignition Drive Circuit)
System Detected Open Circuit DTC B1424: Side-Airbag Module (RH) (Squib) System Detected Short
Circuit DTC B1425: Side-Airbag Module (RH) (Squib) System Detected Open Circuit DTC B1434:
Side-Airbag Module (LH) (Squib) System Fault 3 for Ignition Drive Circuit DTC B1435: Side-Airbag
Module (LH) (Squib) System Fault 4 for Ignition Drive Circuit DTC B1464: Seat Belt Pre-tensioner (RH)
(Squib Ignition Drive Circuit) System Detected Short Circuit DTC B1465: Seat Belt Pre-tensioner (RH)
(Squib Ignition Drive Circuit) System Detected Open Circuit DTC B1466: Analog G-Sensor System in
the SRS-ECU DTC B1467: Safing G-Sensor Open Circuit DTC B1468: Safing G-Sensor Short Circuit
DTC B1469: Safing G-Sensor for Side Air Bag Faults DTC B1474: Seat Belt Pre-tensioner (LH) (Squib
Ignition Drive Circuit) System Detected Short Circuit DTC B1475: Seat Belt Pre-tensioner (LH) (Squib
Ignition Drive Circuit) System Detected Open Circuit DTC B1478: SRS-ECU Capacitor Circuit Voltage
too High DTC B1479: SRS-ECU Capacitor Circuit Voltage too Low DTC B1484: Driver's Air Bag Module
(2nd Squib Ignition Drive Circuit) System Detected Short Circuit DTC B1485: Driver's Air Bag Module
(2nd Squib Ignition Drive Circuit) System Detected Open Circuit DTC B1494: Passenger’s (Front) Air
Bag Module (2nd Squib Ignition Drive Circuit) System Detected Short Circuit DTC B1495: Passenger’s
(Front) Air Bag Module (2nd Squib Ignition Drive Circuit) System Detected Open Circuit DTC B1496:
SRS-ECU Non-Volatile Memory (EEPROM) DTC B1497: SRS-ECU ASIC (for frontal activation) DTC
B1498: SRS-ECU ROM or RAM DTC B1552: Changing Circuit Shorted DTC B1553: Changing Circuit
open DTC B1554: SG BY-PASS Circuit Malfunction DTC B1555: SG BY-PASS Circuit (FET) Open DTC
B1557: SRS-ECU ASIC

CAUTION

If DTCs is set in the SRS-ECU, always diagnose
the CAN main bus line.

DTC SET CONDITIONS

• These DTC are set when a fault is detected in the

SRS-ECU. The most likely causes for this code to
be set are shown in the table below:

TROUBLESHOOTING HINTS

• Malfunction of the SRS-ECU

CODE NO.

PART/CIRCUIT INTEGRAL TO
SRS-ECU

SYMPTOM

B1404

Driver's air bag module (1st squib
ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1405

• Open circuit in the squib ignition drive circuit

B1414

Front passenger's air bag module
(1st squib ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1415

• Open circuit in the squib ignition drive circuit

B1424

Side-airbag module (RH) (squib
ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1425

• Open circuit in the squib ignition drive circuit

B1434

Side-airbag module (LH) (squib
ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1435

• Open circuit in the squib ignition drive circuit

B1464

Seat belt pre-tensioner (RH)
(squib ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1465

• Open circuit in the squib ignition drive circuit

B1466

Analog G-sensor

• When the analog G-sensor is not operating

• When the characteristics of the analog G-sensor are

abnormal

• When the output from the analog G-sensor is

abnormal

SRS AIR BAG DIAGNOSIS

TSB Revision

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-209

.

DIAGNOSIS

Required Special Tool:

• MB991958: Scan Tool (MUT-III Sub Assembly)

• MB991824: Vehicle Communication Interface (V.C.I.)

• MB991827: MUT-III USB Cable

• MB991910: MUT-III Main Harness A (Vehicles with CAN

communication system)

B1467

Safing G-sensor (front air bag)

• Open circuit in the safing G-sensor

B1468

• Short circuit in the safing G-sensor

B1469

Safing G-sensor (side-airbag)

• When the safing G-sensor is not operating

• When the characteristics of the safing G-sensor are

abnormal

• When the output from the safing G-sensor is abnormal

B1474

Seat belt pre-tensioner (LH)
(squib ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1475

• Open circuit in the squib ignition drive circuit

B1478

Capacitor

• Voltage at the capacitor terminal is higher than the

specified value for five seconds or more

B1479

• Voltage at the capacitor terminal is lower than the

specified value for five seconds or more (This is not
detected if DTC No.41 or 42 indicating battery positive
voltage drop has been set).

B1484

Driver's air bag module (2nd
squib ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1485

• Open circuit in the squib ignition drive circuit

B1494

Front passenger's air bag module
(2nd squib ignition drive circuit)

• Short circuit in the squib ignition drive circuit

B1495

• Open circuit in the squib ignition drive circuit

B1496

Non-volatile memory (EEPROM)

• When the non-volatile memory (EEPROM) are

abnormal

B1497

ASIC (for frontal activation)

• When the ASIC (frontal activation) are abnormal

B1498

ROM or RAM

• When the ROM or RAM are abnormal

B1552

Changing of Power Supply

• Short circuit in the changing circuit

B1553

• Open circuit in the changing circuit

B1554

SG-BYPASS

• When the ASIC (frontal activation) are abnormal

B1555

• When the ROM or RAM are abnormal

B1557

ASIC

• When the ASIC are abnormal

CODE NO.

PART/CIRCUIT INTEGRAL TO
SRS-ECU

SYMPTOM