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Home >> Mitsubishi >> 2008 >> Lancer ES, Standard >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> Supplemental Restraint System (SRS) -- Lancer >> SRS Air Bag Diagnosis >> Diagnostic Trouble Code Procedures <SRS-Ecu> >> DTC B1B0B: Passenger's (Front) Air Bag Module (1st squib) System (Short Circuit Between Squib Circuit Terminals); DTC B1B0F: Passenger's (Front) Air Bag Module (2nd squib) System (Short Circuit Between Squib Circuit Terminals) >> Diagnosis
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DTC B1B0B: Passenger's (Front) Air Bag Module (1st squib) System (Short Circuit Between Squib Circuit Terminals); DTC B1B0F: Passenger's (Front) Air Bag Module (2nd squib) System (Short Circuit Between Squib Circuit Terminals): Diagnosis

Required Special Tools: 

  1. STEP 1. Using scan tool MB991958, diagnose the CAN bus line  .
    CAUTION: To prevent damage to scan tool MB991958, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991958.
    1. Connect scan tool MB991958. Refer to "HOW TO CONNECT THE SCAN TOOL  ".
      Fig 1: Connecting Special Tool MB991910 To Data Link Connector
      G05384727Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    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 DIAGNOSIS ).

  2. 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 HOW TO COPE WITH INTERMITTENT MALFUNCTION ).

  3. STEP 3. Check SRS-ECU connector C-122 and passenger's (front) air bag module connector C-16  .
    1. Disconnect the negative battery terminal.
    2. Disconnect connectors C-122 and C-16 then reconnect the m.
    3. While pushing the part "A" indicated in the figure of the harness side connector, turn the lock lever to the direction of the arrow to release the lock lever, and disconnect the C-122 SRS-ECU connector.
      Fig 2: Turning Lock Lever
      G05384728Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. (4)After disconnecting the connector while sliding the C-12 harness side connector to the direction of the arrow, connect the connector again.
    5. Connect the negative battery terminal.
    6. Erase the diagnostic trouble code memory, and check the diagnostic trouble code.
    Fig 3: Sliding C-16 Harness Side Connector
    G05384729Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    Q: Is DTC B1B0B <1st squib> or B1B0F <2nd squib> set? 

    YES  : Go to Step  4.

    NO  : The procedure is complete. It is assumed that DTC B1B0B <1st squib> or B1B0F <2nd squib> set as connector C-122 or C-16 was engaged improperly.

  4. STEP 4. Check the passenger's (front) air bag module  .
    1. Disconnect the negative battery terminal.
    2. Disconnect the passenger's (front) air bag module connector C-16.
    3. Disconnect the connector while sliding the C-16 wiring harness side connector to the direction of the arrow.
      Fig 4: Sliding C-16 Harness Side Connector
      G05384730Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    4. Connect special tool MB991865 to special tool MB991866.
      CAUTION: Do not insert a 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-16 (terminal No.1 and 2 <1st squib> or terminal No.3 and 4 <2nd squib>) by backprobing.
    6. Connect the negative battery terminal.
      Fig 5: Inserting Special Tool MB991866 Into Harness Side Connector C-16
      G05384731Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      CAUTION: Always DTC B1B0E is set when checking DTC B1B0B. This is because the second side terminal is isolated when checking it. DTC B1B0E is set but this is not a fault. In addition, always DTC B1B0A is set when checking DTC B1B0F because the first side terminal is isolated.
    7. Erase the diagnostic trouble code memory, and check the diagnostic trouble code.

    Q: Is the checked DTC set? 

    YES  : Go to Step  5.

    NO  : Replace the passenger's (front) air bag module (Refer to AIR BAG MODULE(S) AND CLOCK SPRING ). Then go to Step  7.

  5. STEP 5. Check the passenger's (front) air bag module circuit at SRS-ECU connector C-122  .
    1. Disconnect SRS-ECU connector C-122.
    2. While pushing the part "A" indicated in the figure of the harness side connector, turn the lock lever to the direction of the arrow to release the lock lever, and disconnect the C-122 SRS-ECU connector.

      DANGER 

      To prevent the air bag from deploying unintentionally, disconnect the passenger's (front) air bag module connector C-16 to short the squib circuit  .

      Fig 6: Turning Lock Lever
      G05384732Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    3. Disconnect the passenger's (front) air bag module connector C-16.
    4. Disconnect the connector while sliding the C-16 wiring harness side connector to the direction of the arrow.
      Fig 7: Sliding C-16 Harness Side Connector
      G05384733Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      CAUTION: Insert an insulator such as a cable tie to a depth of 4 mm (0.16 inch) or more, otherwise the short spring will not be released.
    5. Insert a cable tie [3 mm (0.12 inch) wide, 0.5 mm (0.02 inch) thick] between terminals 7 and 8 <1st squib> or 11 and 12 <2nd squib>, and the short spring to release the short spring.
      Fig 8: Inserting Cable Tie Between Terminals 7 And 8
      G05384734Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      Fig 9: Inserting Cable Tie Between Terminals 11 And 12
      G05384735Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
    6. Check for continuity between C-122 harness side connector terminals 7 and 8 <1st squib> or 11 and 12 <2nd squib>.
      7. Fig 10: Checking Continuity Between C-122 Harness Side Connector Terminals 7 And 8
      G05384736Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
      Fig 11: Checking Continuity Between C-122 Harness Side Connector Terminals 11 And 12
      G05384737Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

    It should be open circuit.

    Q: Does continuity exist? 

    YES  : Go to Step  6.

    NO  : Erase the diagnostic trouble code memory, and check the diagnostic trouble code. If DTC B1B0B <1st squib> or B1B0F <2nd squib> set, replace the SRS-ECU (Refer to SRS CONTROL UNIT (SRS-ECU) ). Then go to Step  7.

  6. STEP 6. Check the harness for short circuit between SRS-ECU connector C-122 (terminal No.7 and 8 <1st squib> or terminal No.11 and 12 <2nd squib>) and passenger's (front) air bag module connector C-16 (terminal No.2 and 1 <1st squib> terminal No.4 and 3 <2nd squib>)  .

    Q: Are harness wires between SRS-ECU connector C-122 (terminal No.7 and 8 <1st squib> or terminal No.11 and 12 <2nd squib>) and passenger's (front) air bag module connector C-16 (terminal No.2 and 1 <1st squib> terminal No.4 and 3 <2nd squib>) in good condition? 

    YES  : Go to Step  7.

    NO  : Replace the harness wires between SRS-ECU connector C-122 and passenger's (front) air bag module connector C-16. Then go to Step  7.

  7. STEP 7. Check 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 B1B0B <1st squib> or B1B0F <2nd squib> set? 

    YES  : Return to Step  1.

    NO  : The procedure is complete.

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