Mitsubishi 380. Manual — part 812

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-172

STEP 5. Check harness wires for short circuit to ground
between SRS-ECU connector D-26 (terminal No.59 and 60)
and driver's seat belt pre-tensioner connector D-33
(terminal No.1 and 2).
Q: Are the harness wires between SRS-ECU connector

D-26 (terminal No.59 and 60) and driver'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 D-26 and driver'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.

AC307915AC

CONNECTOR: D-33

D-33 (B)

FORWARD

CENTER
PILLAR

HARNESS SIDE
CONNECTOR
(FRONT VIEW)

2 1

24DB063A

CONNECTOR: D-26

SRS-ECU

63

55

51

69

61

66

58

65

64

5657

68

60

67

59

70

62

53

52 B A

54

D-26 (Y)

D-26 FLOOR

HARNESS

CONNECTOR

(REAR VIEW)

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-173

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 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

• Refer to circuit diagrams GROUP-

90

• Refer to configuration diagrams GROUP-

80

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

B1467

Safing G-sensor (front air bag)

• Open circuit in the safing G-sensor

B1468

• Short circuit in the safing G-sensor

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-174

.

DIAGNOSIS

Required Special Tool:

• MB991958: diagnostic 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)

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).

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

SRS AIR BAG DIAGNOSIS

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-175

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 DTCs set?

YES : Replace the SRS-ECU (Refer to

P.52B-234

).

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