AIRBAG SYSTEM, Diagnostic DTC:B1637/82

DTC Code DTC Name
B1637/82 Lost Communication with Rear Airbag Sensor LH

DESCRIPTION

The side collision sensor LH circuit (to determine deployment of the front seat side airbag assembly LH and curtain shield airbag assembly LH) is composed of the airbag sensor assembly, side airbag sensor assembly LH and No. 2 side airbag sensor assembly LH.

The side airbag sensor assembly LH and No. 2 side airbag sensor assembly LH detect impacts to the vehicle and send signals to the airbag sensor assembly to determine if the airbag should be deployed.

This DTC is stored when a malfunction is detected in the side collision sensor LH circuit (to determine deployment of the front seat side airbag assembly LH and curtain shield airbag assembly LH).

DTC No. DTC Detection Condition Trouble Area
B1637/82

  • The airbag sensor assembly receives a line short circuit signal, an open circuit signal, a short circuit to ground signal or a short circuit to B+ signal in the side collision sensor LH circuit (to determine deployment of the front seat side airbag assembly LH and curtain shield airbag assembly LH).

  • Side airbag sensor assembly LH malfunction

  • No. 2 side airbag sensor assembly LH malfunction

  • Airbag sensor assembly malfunction

  • Floor wire

  • Side airbag sensor assembly LH

  • No. 2 side airbag sensor assembly LH

  • Airbag sensor assembly

WIRING DIAGRAM

A01V21KE02
*a Side Airbag Sensor Assembly LH
*b No. 2 Side Airbag Sensor Assembly LH
*c Airbag Sensor Assembly

PROCEDURE


  1. CHECK CONNECTORS


    1. Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) auxiliary battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) auxiliary battery terminal to disable the SRS system.

    3. Check that the connectors are properly connected to the airbag sensor assembly, side airbag sensor assembly LH and No. 2 side airbag sensor assembly LH.

      OK
      The connectors are properly connected.

      Tech Tips

      If the connectors are not connected securely, reconnect the connectors and proceed to the next inspection.

    4. Disconnect the connectors from the airbag sensor assembly, side airbag sensor assembly LH and No. 2 side airbag sensor assembly LH.

    5. Check that the terminals of connectors are not damaged.

      OK
      The terminals are not deformed or damaged.

    NG

    REPLACE WIRE HARNESS

    OK

  2. CHECK FLOOR WIRE (OPEN)


    1. Using a service wire, connect terminals 2 (BCL+) and 1 (BCL-) of connector C.

      A01V1LDE01
      Text in Illustration
      *1 No. 2 Side Airbag Sensor Assembly LH *2 Side Airbag Sensor Assembly LH
      *3 Floor Wire *4 Connector B
      *5 Connector C *6 Service Wire
      *a

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)

      		 *b

      Front view of wire harness connector

      (to No. 2 Side Airbag Sensor Assembly LH)

      Note

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K18-1 (BCL+) - K18-2 (BCL-) Always Below 1 Ω

    3. Disconnect the service wire from connector C.


    NG

    REPLACE FLOOR WIRE

    OK

  3. CHECK FLOOR WIRE (SHORT)


    1. A01UXP6E02
      Text in Illustration
      *1 No. 2 Side Airbag Sensor Assembly LH
      *2 Side Airbag Sensor Assembly LH
      *3 Floor Wire
      *4 Connector B
      *a

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K18-1 (BCL+) - K18-2 (BCL-) Always 1 MΩ or higher

    NG

    REPLACE FLOOR WIRE

    OK

  4. CHECK FLOOR WIRE (SHORT TO B+)


    1. A01UXP6E03
      Text in Illustration
      *1 No. 2 Side Airbag Sensor Assembly LH
      *2 Side Airbag Sensor Assembly LH
      *3 Floor Wire
      *4 Connector B
      *a

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)

      Connect the cable to the negative (-) auxiliary battery terminal.

    2. Turn the ignition switch to ON (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      K18-1 (BCL+) - Body ground Ignition switch ON (IG) Below 1 V
      K18-2 (BCL-) - Body ground Ignition switch ON (IG) Below 1 V

    4. Turn the ignition switch off.

    5. Disconnect the cable from the negative (-) auxiliary battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) auxiliary battery terminal to disable the SRS system.


    NG

    REPLACE FLOOR WIRE

    OK

  5. CHECK FLOOR WIRE (SHORT TO GROUND)


    1. A01UXP6E01
      Text in Illustration
      *1 No. 2 Side Airbag Sensor Assembly LH
      *2 Side Airbag Sensor Assembly LH
      *3 Floor Wire
      *4 Connector B
      *a

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K18-1 (BCL+) - Body ground Always 1 MΩ or higher
      K18-2 (BCL-) - Body ground Always 1 MΩ or higher

    NG

    REPLACE FLOOR WIRE

    OK

  6. CHECK SIDE AIRBAG SENSOR ASSEMBLY LH


    1. A01V1M0E02
      Text in Illustration
      *1 Side Airbag Sensor Assembly RH
      *2 Airbag Sensor Assembly

      Connect the connectors to the No. 2 side airbag sensor assembly LH and airbag sensor assembly.

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

    3. Connect the cable to the negative (-) auxiliary battery terminal.

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

    5. Clear the DTCs stored in the memory Click here.

    6. Turn the ignition switch off.

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

    8. Check for DTCs Click here.

      Result
      Result Proceed to
      DTC B1637/82 is output. A
      DTC B1632/81 is output. B
      DTCs B1632/81 or B1637/82 is not output. C

      Tech Tips

      Codes other than DTCs B1632/81 and B1637/82 may be output at this time, but they are not related to this check.

    9. Turn the ignition switch off.

    10. Disconnect the cable from the negative (-) auxiliary battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) auxiliary battery terminal to disable the SRS system.

    11. Return the side airbag sensor assembly LH and the side airbag sensor assembly RH to their original positions and connect the connectors to them.


    B

    REPLACE SIDE AIRBAG SENSOR ASSEMBLY LH Click here

    C

    USE SIMULATION METHOD TO CHECK Click here

    A

  7. CHECK NO. 2 SIDE AIRBAG SENSOR ASSEMBLY LH


    1. A01UYHAE28
      Text in Illustration
      *1 No. 2 Side Airbag Sensor Assembly RH
      *2 Side Airbag Sensor Assembly LH

      Interchange the No. 2 side airbag sensor assembly LH with the No. 2 side airbag sensor assembly RH and connect the connectors to them.

    2. Connect the cable to the negative (-) auxiliary battery terminal.

    3. Turn the ignition switch to ON (IG), and wait for at least 60 seconds.

    4. Clear the DTCs stored in the memory Click here.

    5. Turn the ignition switch off.

    6. Turn the ignition switch to ON (IG), and wait for at least 60 seconds.

    7. Check for DTCs Click here.

      Result
      Result Proceed to
      DTCs B1632/81 or B1637/82 is not output. A
      DTC B1637/82 is output. B
      DTC B1632/81 is output. C

      Tech Tips

      Codes other than DTCs B1632/81 and B1637/82 may be output at this time, but they are not related to this check.

    8. Turn the ignition switch off.

    9. Disconnect the cable from the negative (-) auxiliary battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) auxiliary battery terminal to disable the SRS system.

    10. Return the No. 2 side airbag sensor assembly LH and the No. 2 side airbag sensor assembly RH to their original positions and connect the connectors to them.


    A

    USE SIMULATION METHOD TO CHECK Click here

    B

    REPLACE AIRBAG SENSOR ASSEMBLY Click here

    C

    REPLACE NO. 2 SIDE AIRBAG SENSOR ASSEMBLY LH Click here