AIRBAG SYSTEM, Diagnostic DTC:B1617, B1618

DTC Code DTC Name
B1617 Front Airbag Sensor Lost Communication (LH)
B1618 Front Airbag Sensor Initialization Error (LH)

DESCRIPTION

The front airbag sensor LH circuit consists of the center airbag sensor and front airbag sensor LH.

The front airbag sensor LH detects impacts to the vehicle and sends signals to the center airbag sensor to determine if the airbag should be deployed.

DTC B1617 or B1618 is stored when a malfunction is detected in the front airbag sensor LH circuit.

DTC Code DTC Detection Condition Trouble Area
B1617

One of the following conditions is met:


  • The center airbag sensor detects a line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to B+ signal in the front airbag sensor LH circuit for 2 seconds.

  • A front airbag sensor LH malfunction.

  • A center airbag sensor malfunction.

  • Instrument panel wire

  • Engine room main wire

  • Front airbag sensor LH

  • Center airbag sensor
B1618

One of the following conditions is met:


  • The center airbag sensor detects a line short circuit signal, open circuit signal, short circuit to ground signal or short circuit to B+ signal in the front airbag sensor LH circuit for 2 seconds.

  • A front airbag sensor LH malfunction.

  • A center airbag sensor malfunction.

  • Instrument panel wire

  • Engine room main wire

  • Front airbag sensor LH

  • Center airbag sensor

WIRING DIAGRAM

B001CQ0E04
*a Front Airbag Sensor LH
*b Center Airbag Sensor

CAUTION / NOTICE / HINT

Note


  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

  • When disconnecting the cable from the negative (-) battery terminal while performing repairs, some systems need to be initialized after the cable is reconnected Click here.

  • After replacing the center airbag sensor, refer to initialization Click here.

PROCEDURE


  1. CHECK CONNECTION OF CONNECTORS


    1. Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

    3. Check that the connectors are properly connected to the center airbag sensor and front airbag sensor LH.

      OK
      The connectors are properly connected.

    NG

    CONNECT CONNECTORS PROPERLY

    OK

  2. CHECK CONNECTORS


    1. Disconnect the connectors from the center airbag sensor and front airbag sensor LH.

    2. B001FQZC01
      *A w/o Side Airbag
      *B w/ Side Airbag
      *1 Front Airbag Sensor RH
      *2 Center Airbag Sensor

      Check that the connectors (on the center airbag sensor side and front airbag sensor LH side) are not damaged.

      OK
      The connectors are not deformed or damaged.

    NG

    REPLACE ENGINE ROOM MAIN WIRE OR INSTRUMENT PANEL WIRE

    OK

  3. CHECK FRONT AIRBAG SENSOR LH CIRCUIT


    1. w/o Side Airbag


      1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

        B001CO3E01
        Text in Illustration
        *1 Front Airbag Sensor LH *2 Center Airbag Sensor
        *3 Connector E *4 Connector B
        *5 Service Wire - -
        *a

        Front view of wire harness connector

        (to Front Airbag Sensor LH)

        		 *b

        Rear view of wire harness connector

        (to Center Airbag Sensor)

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        A21-2 (+SL) - Body ground Ignition switch ON Below 1 V
        A21-1 (-SL) - Body ground Ignition switch ON Below 1 V

      3. Turn the ignition switch off.

      4. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

      5. Using a service wire, connect terminals 30 (+SL) and 28 (-SL) of connector B.

        Note

        Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

      6. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        A21-2 (+SL) - A21-1 (-SL) Always Below 1 Ω

      7. Disconnect the service wire from connector B.

      8. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        A21-2 (+SL) - A21-1 (-SL) Always 1 MΩ or higher
        A21-2 (+SL) - Body ground Always 1 MΩ or higher
        A21-1 (-SL) - Body ground Always 1 MΩ or higher

    2. w/ Side Airbag


      1. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

        B001DFLC10
        *1 Front Airbag Sensor LH *2 Airbag ECU Assembly
        *3 Connector E *4 Connector B
        *5 Service Wire - -
        *a

        Front view of wire harness connector

        (to Front Airbag Sensor LH)

        		 *b

        Rear view of wire harness connector

        (to Airbag ECU Assembly)

      2. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        A21-2 (+SL) - Body ground Ignition switch ON Below 1 V
        A21-1 (-SL) - Body ground Ignition switch ON Below 1 V

      3. Turn the ignition switch off.

      4. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

      5. Using a service wire, connect terminals 30 (+SL) and 28 (-SL) of connector B.

        Note

        Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

      6. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        A21-2 (+SL) - A21-1 (-SL) Always Below 1 Ω

      7. Disconnect the service wire from connector B.

      8. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        A21-2 (+SL) - A21-1 (-SL) Always 1 MΩ or higher
        A21-2 (+SL) - Body ground Always 1 MΩ or higher
        A21-1 (-SL) - Body ground Always 1 MΩ or higher

    NG

    CHECK INSTRUMENT PANEL WIRE (CENTER AIRBAG SENSOR - ENGINE ROOM MAIN WIRE) Click here

    OK

  4. CHECK FRONT AIRBAG SENSOR LH


    1. B001GX5C01
      *A w/o Side Airbag
      *B w/ Side Airbag
      *1 Front Airbag Sensor LH
      *2 Center Airbag Sensor

      Connect the connectors to the center airbag sensor.

    2. Interchange the front airbag sensor LH with RH and connect the connectors to them.

    3. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

    4. Turn the ignition switch to ON, and wait for at least 60 seconds.

    5. Clear the DTCs stored in memory Click here.

    6. Turn the ignition switch off.

    7. Turn the ignition switch to ON, and wait for at least 60 seconds.

    8. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1617 or B1618 is output A
      DTC B1612 or B1613 is output B
      DTC B1612, B1613, B1617 and B1618 are not output C

      Tech Tips

      Codes other than DTC B1612, B1613, B1617 and B1618 may be output at this time, but they are not related to this check.


    C

    USE SIMULATION METHOD TO CHECK Click here

    A

    REPLACE CENTER AIRBAG SENSOR Click here

    B

    REPLACE FRONT AIRBAG SENSOR LH Click here

  5. CHECK INSTRUMENT PANEL WIRE (CENTER AIRBAG SENSOR - ENGINE ROOM MAIN WIRE)


    1. w/o Side Airbag


      1. Disconnect the instrument panel wire connector from the engine room main wire.

        B001HF5E01
        Text in Illustration
        *1 Front Airbag Sensor LH *2 Center Airbag Sensor
        *3 Engine Room Main Wire *4 Instrument Panel Wire
        *5 Connector C *6 Connector B
        *7 Service Wire - -
        *a

        Front view of wire harness connector

        (to Engine Room Main Wire)

        		 *b

        Rear view of wire harness connector

        (to Center Airbag Sensor)

      2. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

      3. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        GA5-3 (+SL) - Body ground Ignition switch ON Below 1 V
        GA5-4 (-SL) - Body ground Ignition switch ON Below 1 V

      4. Turn the ignition switch off.

      5. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

      6. Using a service wire, connect terminals 30 (+SL) and 28 (-SL) of connector B.

        Note

        Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

      7. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        GA5-3 (+SL) - GA5-4 (-SL) Always Below 1 Ω

      8. Disconnect the service wire from connector B.

      9. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        GA5-3 (+SL) - GA5-4 (-SL) Always 1 MΩ or higher
        GA5-3 (+SL) - Body ground Always 1 MΩ or higher
        GA5-4 (-SL) - Body ground Always 1 MΩ or higher

    2. w/ Side Airbag


      1. Disconnect the instrument panel wire connector from the engine room main wire.

        B001FV1C01
        *1 Front Airbag Sensor LH *2 Center Airbag Sensor
        *3 Engine Room Main Wire *4 Instrument Panel Wire
        *5 Connector C *6 Connector B
        *7 Service Wire - -
        *a

        Front view of wire harness connector

        (to Engine Room Main Wire)

        		 *b

        Rear view of wire harness connector

        (to Center Airbag Sensor)

      2. Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

      3. Measure the voltage according to the value(s) in the table below.

        Standard Voltage
        Tester Connection Switch Condition Specified Condition
        GA5-3 (+SL) - Body ground Ignition switch ON Below 1 V
        GA5-4 (-SL) - Body ground Ignition switch ON Below 1 V

      4. Turn the ignition switch off.

      5. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

      6. Using a service wire, connect terminals 30 (+SL) and 28 (-SL) of connector B.

        Note

        Do not forcibly insert the service wire into the terminals of the connector when connecting a service wire.

      7. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        GA5-3 (+SL) - GA5-4 (-SL) Always Below 1 Ω

      8. Disconnect the service wire from connector B.

      9. Measure the resistance according to the value(s) in the table below.

        Standard Resistance
        Tester Connection Condition Specified Condition
        GA5-3 (+SL) - GA5-4 (-SL) Always 1 MΩ or higher
        GA5-3 (+SL) - Body ground Always 1 MΩ or higher
        GA5-4 (-SL) - Body ground Always 1 MΩ or higher

    OK

    REPLACE ENGINE ROOM MAIN WIRE

    NG

    REPLACE INSTRUMENT PANEL WIRE