AIRBAG SYSTEM, Diagnostic DTC:B1638

DTC Code DTC Name
B1638 Curtain Shield Airbag Sensor Initialization Error (LH)

DESCRIPTION

The circuit for the side collision sensor LH is composed of the airbag ECU assembly, door side airbag sensor LH, side airbag sensor assembly LH and rear airbag sensor LH.

The rear airbag sensor LH detect impacts to the vehicle and send signals to the airbag ECU assembly to determine if the airbag should be deployed.

DTC B1638 is stored when a malfunction is detected in the circuit for the side collision sensor LH.

DTC No. Detection Item DTC Detection Condition Trouble Area Warning Indicate Test Mode / Check Mode
B1638 Curtain Shield Airbag Sensor Initialization Error (LH)

One of the following conditions is met:


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

  • A rear airbag sensor LH malfunction.

  • An airbag ECU assembly malfunction.

  • Floor wire

  • Front door wire LH

  • Rear airbag sensor LH

  • Airbag ECU assembly

 Comes on Not applicable

WIRING DIAGRAM

B0069WDE06
*a Rear Airbag Sensor LH
*b Door Side Airbag Sensor LH
*c Side Airbag Sensor Assembly LH
*d Airbag ECU Assembly

CAUTION / NOTICE / HINT

Note


  • After turning the engine switch off, waiting time may be required before disconnecting the cable from the negative (-) battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) battery terminal notices 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

PROCEDURE


  1. CHECK PAST DTC


    1. Turn the engine switch on (IG), and wait for at least 60 seconds.

    2. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1637 is not output
      DTC B1637 is output

    DTC B1637 is output

    GO TO DTC B1637 Click here

    DTC B1637 is not output

  2. CHECK DTC


    1. Turn the engine switch off.

      Tech Tips

      If a communication error occurs, DTCs for both the LH and RH sides will be stored simultaneously. The malfunctioning area can be identified by turning the engine switch off and then on (IG) again.

    2. Turn the engine switch on (IG), and wait for at least 60 seconds.

    3. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1638 is output
      DTC B1638 is not output

      Tech Tips

      Codes other than DTC B1638 may be output at this time, but they are not related to this check.


    DTC B1638 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1638 is output

  3. CHECK CONNECTION OF CONNECTORS


    1. Turn the engine 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 airbag ECU assembly and rear airbag sensor LH.

      Result
      Proceed to
      The connectors are properly connected
      The connectors are not properly connected

    The connectors are not properly connected

    CONNECT CONNECTORS PROPERLY

    The connectors are properly connected

  4. CHECK CONNECTORS


    1. Disconnect the connectors from the airbag ECU assembly and rear airbag sensor LH.

    2. B006DLWC32
      *1 Rear Airbag Sensor LH
      *2 Airbag ECU Assembly
      *3 Floor Wire

      Check that the connectors (on the airbag ECU assembly side and rear airbag sensor LH side) are not damaged.

      Result
      Proceed to
      The connectors are not deformed or damaged
      The connectors are deformed or damaged

    The connectors are deformed or damaged

    REPLACE FLOOR WIRE

    The connectors are not deformed or damaged

  5. CHECK FLOOR WIRE


    1. B006BLIC07
      *1 Rear Airbag Sensor LH
      *2 Airbag ECU Assembly
      *3 Floor Wire
      *4 Service Wire
      *a

      Front view of wire harness connector

      (to Rear Airbag Sensor LH)
      *b

      Front view of wire harness connector

      (to Airbag ECU Assembly)

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

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      L63-4 (BCL+) - Body ground Engine switch on (IG) Below 1 V
      L63-3 (BCL-) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine 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 32 (BBL+) and 31 (BBL-) 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
      L63-4 (BCL+) - L63-3 (BCL-) 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
      L63-4 (BCL+) - L63-3 (BCL-) Always 1 MΩ or higher
      L63-4 (BCL+) - Body ground Always 1 MΩ or higher
      L63-3 (BCL-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  6. CHECK REAR AIRBAG SENSOR LH


    1. B006EVEC01
      *1 Rear Airbag Sensor RH
      *2 Airbag ECU Assembly

      Connect the connectors to the airbag ECU assembly.

    2. Interchange the rear 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 engine switch on (IG), and wait for at least 60 seconds.

    5. Clear the DTCs stored in memory.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    6. Turn the engine switch off.

    7. Turn the engine switch on (IG), and wait for at least 60 seconds.

    8. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1633 is output
      DTC B1638 is output
      DTC B1633 and B1638 are not output

      Tech Tips

      Codes other than DTC B1633 and B1638 may be output at this time, but they are not related to this check.

    9. Turn the engine switch off.

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

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


    DTC B1633 is output

    REPLACE REAR AIRBAG SENSOR LH Click here

    DTC B1633 and B1638 are not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1638 is output

  7. CHECK CONNECTION OF CONNECTOR


    1. Check that the connector is properly connected to the side airbag sensor assembly LH.

      Result
      Proceed to
      The connector is properly connected
      The connector is not properly connected

    The connector is not properly connected

    CONNECT CONNECTOR PROPERLY

    The connector is properly connected

  8. CHECK CONNECTOR


    1. Disconnect the connectors from the side airbag sensor assembly LH and rear airbag sensor LH.

    2. B006DNRC05
      *1 Side Airbag Sensor Assembly LH
      *2 Rear Airbag Sensor LH
      *3 Floor Wire

      Check that the connector (on the side airbag sensor assembly LH side) is not damaged.

      Result
      Proceed to
      The connector is not deformed or damaged
      The connector is deformed or damaged

    The connector is deformed or damaged

    REPLACE FLOOR WIRE

    The connector is not deformed or damaged

  9. CHECK FLOOR WIRE


    1. B006BI1C03
      *1 Side Airbag Sensor Assembly LH
      *2 Rear Airbag Sensor LH
      *3 Floor Wire
      *4 Service Wire
      *a

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)
      *b

      Front view of wire harness connector

      (to Rear Airbag Sensor LH)

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

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      L66-4 (BBL+) - Body ground Engine switch on (IG) Below 1 V
      L66-3 (BBL-) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine 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 1 (BBL+) and 2 (BBL-) 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
      L66-4 (BBL+) - L66-3 (BBL-) 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
      L66-4 (BBL+) - L66-3 (BBL-) Always 1 MΩ or higher
      L66-4 (BBL+) - Body ground Always 1 MΩ or higher
      L66-3 (BBL-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  10. CHECK CONNECTION OF CONNECTOR


    1. Check that the connector is properly connected to the door side airbag sensor LH.

      Result
      Proceed to
      The connector is properly connected
      The connector is not properly connected

    The connector is not properly connected

    CONNECT CONNECTOR PROPERLY

    The connector is properly connected

  11. CHECK CONNECTOR


    1. Disconnect the connectors from the door side airbag sensor LH.

    2. B0069TVC08
      *1 Door Side Airbag Sensor LH
      *2 Side Airbag Sensor Assembly LH
      *3 Front Door Wire LH
      *4 Floor Wire

      Check that the connector (on the door side airbag sensor LH side) is not damaged.

      Result
      Proceed to
      The connector is not deformed or damaged
      The connector is deformed or damaged

    The connector is deformed or damaged

    REPLACE FRONT DOOR WIRE LH

    The connector is not deformed or damaged

  12. CHECK DOOR SIDE AIRBAG SENSOR LH CIRCUIT


    1. B0069H5C10
      *1 Door Side Airbag Sensor LH
      *2 Side Airbag Sensor Assembly LH
      *3 Front Door Wire LH
      *4 Floor Wire
      *5 Service Wire
      *a

      Front view of wire harness connector

      (to Door Side Airbag Sensor LH)
      *b

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)

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

    2. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      H27-2 (BDL+) - Body ground Engine switch on (IG) Below 1 V
      H27-1 (BDL-) - Body ground Engine switch on (IG) Below 1 V

    4. Turn the engine 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 1 (BDL+) and 2 (BDL-) 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
      H27-2 (BDL+) - H27-1 (BDL-) 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
      H27-2 (BDL+) - H27-1 (BDL-) Always 1 MΩ or higher
      H27-2 (BDL+) - Body ground Always 1 MΩ or higher
      H27-1 (BDL-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    CHECK FLOOR WIRE Click here

    OK

  13. CHECK DTC


    1. B006DQSC15
      *1 Door Side Airbag Sensor LH
      *2 Side Airbag Sensor Assembly LH

      Connect the connectors to the door side airbag sensor LH and side airbag sensor assembly LH.

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

    3. Turn the engine switch on (IG), and wait for at least 60 seconds.

    4. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    5. Turn the engine switch off.

    6. Turn the engine switch on (IG), and wait for at least 60 seconds.

    7. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1638 is output
      DTC B1638 is not output

      Tech Tips

      Codes other than DTC B1638 may be output at this time, but they are not related to this check.


    DTC B1638 is output

    REPLACE AIRBAG ECU ASSEMBLY Click here

    DTC B1638 is not output

    USE SIMULATION METHOD TO CHECK Click here

  14. CHECK FLOOR WIRE


    1. B006EZ8C05
      *1 Door Side Airbag Sensor LH
      *2 Side Airbag Sensor Assembly LH
      *3 Front Door Wire LH
      *4 Floor Wire
      *5 Service Wire
      *a

      Front view of wire harness connector

      (to Front Door Wire LH)
      *b

      Front view of wire harness connector

      (to Side Airbag Sensor Assembly LH)

      Disconnect the floor wire connector from the front door wire LH.

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

    3. Turn the engine switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      L 2-10 (BDL+) - Body ground Engine switch on (IG) Below 1 V
      L 2-20 (BDL-) - Body ground Engine switch on (IG) Below 1 V

    5. Turn the engine switch off.

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

    7. Using a service wire, connect terminals 1 (BDL+) and 2 (BDL-) of connector B.

      Note

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

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L 2-10 (BDL+) - L 2-20 (BDL-) Always Below 1 Ω

    9. Disconnect the service wire from connector B.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      L 2-10 (BDL+) - L 2-20 (BDL-) Always 1 MΩ or higher
      L 2-10 (BDL+) - Body ground Always 1 MΩ or higher
      L 2-20 (BDL-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE FRONT DOOR WIRE LH

    NG

    REPLACE FLOOR WIRE