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Home >> Scion >> 2010 >> xD Standard >> Repair and Diagnosis (Single Page) >> Restraints >> Air Bag, SRS >> Supplemental Restraint System (Diagnostic Codes & Symptom Tests) >> Airbag System >> DTC B1623/81: Driver Side - Side Airbag Sensor Assembly Initialization Incomplete; DTC B1628/82: Front Passenger Side - Side Airbag Sensor Assembly Initialization Incomplete; DTC B1643/81: Driver Side Satellite Sensor Bus Initialization Incomplete; DTC B1648/82: Front Passenger Side Satellite Sensor Bus Initialization Incomplete >> Procedure
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DTC B1623/81: Driver Side - Side Airbag Sensor Assembly Initialization Incomplete; DTC B1628/82: Front Passenger Side - Side Airbag Sensor Assembly Initialization Incomplete; DTC B1643/81: Driver Side Satellite Sensor Bus Initialization Incomplete; DTC B1648/82: Front Passenger Side Satellite Sensor Bus Initialization Incomplete: Procedure

  1. CHECK PAST DTC 
    1. Turn the ignition switch to ON, and wait for at least 60 seconds.
    2. Turn the ignition switch to OFF.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Check the past DTCs. Refer to DTC CHECK / CLEAR .
      RESULT:

      Result Proceed to
      DTC B1622 or B1627 is output A
      DTC B1632 or B1637 is output B
      DTC B1622, B1627, B1632 and B1637 are not output C

    B → See step   20 

    A → See step   19 

    C: Go to next step 

  2. CHECK FOR DTC 
    1. Turn the ignition switch to OFF.
    2. Turn the ignition switch to ON, and wait for at least 60 seconds.
    3. Check for DTCs. Refer to DTC CHECK / CLEAR .
      RESULT:

      Result Proceed to
      DTC B1623, B1628, B1643 and B1648 are not output A
      DTC B1623 or B1643 is output B
      DTC B1628 or B1648 is output C

    B → See step   11 

    A → See step   21 

    C: Go to next step 

  3. CHECK CONNECTION OF CONNECTORS 
    1. Turn the ignition switch to OFF.
    2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    3. Check that the connectors are properly connected to the center airbag sensor and side airbag sensor RH.

      OK

      The connectors are properly connected.

    NG → CONNECT CONNECTORS PROPERLY 

    OK: Go to next step 

  4. CHECK CONNECTORS 
    1. Disconnect the connectors from the center airbag sensor and side airbag sensor RH.
    2. Check that the connectors (on the center airbag sensor side and side airbag sensor RH side) are not damaged.

      OK

      The connectors are not deformed or damaged.

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  5. CHECK FLOOR WIRE (CENTER AIRBAG SENSOR - SIDE AIRBAG SENSOR RH) 
    Fig 1: Identifying L19 And L11 Connector Terminals
    GTY158339Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      L19-4 (BBR+) - Body ground Ignition switch ON Below 1 V
      L19-3 (BBR-) - Body ground Ignition switch ON Below 1 V
    4. Turn the ignition switch to OFF.
    5. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    6. Using a service wire, connect terminals 8 (BBP+) and 11 (BBP-) of connector B.
      NOTE:

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

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

      Standard resistance

      Tester Connection Condition Specified Condition
      L19-4 (BBR+) - L19-3 (BBR-) 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
      L19-4 (BBR+) - L19-3 (BBR-) Always 1 MΩ or higher
      L19-4 (BBR+) - Body ground Always 1 MΩ or higher
      L19-3 (BBR-) - Body ground Always 1 MΩ or higher

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  6. CHECK CONNECTION OF CONNECTORS 
    1. Check that the connector is properly connected to the rear airbag sensor RH.

      OK

      The connector is properly connected.

    NG → CONNECT CONNECTOR PROPERLY 

    OK: Go to next step 

  7. CHECK CONNECTORS 
    1. Disconnect the connectors from the side airbag sensor RH and rear airbag sensor RH.
    2. Check that the connector (on the rear airbag sensor RH side) is not damaged.

      OK

      The connector is not deformed or damaged.

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  8. CHECK FLOOR WIRE (SIDE AIRBAG SENSOR RH - REAR AIRBAG SENSOR RH) 
    Fig 2: Identifying L17 And L19 Connector Terminals
    GTY162835Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      L19-1 (BCR+) - Body ground Ignition switch ON Below 1 V
      L19-2 (BCR-) - Body ground Ignition switch ON Below 1 V
    4. Turn the ignition switch to OFF.
    5. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    6. Using a service wire, connect terminals 2 (BCR+) and 1 (BCR-) of connector C.
      NOTE:

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

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

      Standard resistance

      Tester Connection Condition Specified Condition
      L19-1 (BCR+) - L19-2 (BCR-) Always Below 1 Ω
    8. Disconnect the service wire from connector C.
    9. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      L19-1 (BCR+) - L19-2 (BCR-) Always 1 MΩ or higher
      L19-1 (BCR+) - Body ground Always 1 MΩ or higher
      L19-2 (BCR-) - Body ground Always 1 MΩ or higher

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  9. CHECK SIDE AIRBAG SENSOR RH 
    Fig 3: Identifying Side Airbag Sensor LH
    GTY158590Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Interchange the side airbag sensor LH with RH and connect the connectors to them.
    2. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    5. Turn the ignition switch to OFF.
    6. Turn the ignition switch to ON, and wait for at least 90 seconds.
    7. Check for DTCs. Refer to DTC CHECK / CLEAR .
      RESULT

      Result Proceed to
      DTC B1623, B1628, B1643 and B1648 are not output A
      DTC B1623 or B1643 is output B
      DTC B1628 or B1648 is output C
    8. Turn the ignition switch to OFF.
    9. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    10. Return the side airbag sensor LH and RH to their original position and connect the connectors to them.

    B → See step   22 

    A → See step   23 

    C: Go to next step 

  10. CHECK REAR AIRBAG SENSOR RH 
    Fig 4: Identifying Rear Airbag Sensor LH
    GTY111008Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Interchange the rear airbag sensor LH with RH and connect the connectors to them.
    2. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    5. Turn the ignition switch to OFF.
    6. Turn the ignition switch to ON, and wait for at least 90 seconds.
    7. Check for DTCs. Refer to DTC CHECK / CLEAR .
      RESULT

      Result Proceed to
      DTC B1623 or B1643 is output A
      DTC B1628 or B1648 is output B
      DTC B1623, B1628, B1643 and B1648 are not output C

      HINT: 

      Codes other than DTC B1623, B1628, B1643 and B1648 may be output at this time, but they are not related to this check.

    8. Turn the ignition switch to OFF.
    9. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    10. Return the rear airbag sensor RH and LH to their original position and connect the connectors to them.

    B → See step   25 

    A → See step   24 

    C → See step   23 

  11. CHECK CONNECTION OF CONNECTORS 
    1. Turn the ignition switch to OFF.
    2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    3. Check that the connectors are properly connected to the center airbag sensor and side airbag sensor LH.

      OK

      The connectors are properly connected.

    NG → CONNECT CONNECTORS PROPERLY 

    OK: Go to next step 

  12. CHECK CONNECTORS 
    1. Disconnect the connectors from the center airbag sensor and side airbag sensor LH.
    2. Check that the connectors (on the center airbag sensor side and side airbag sensor LH side) are not damaged.

      OK

      The connectors are not deformed or damaged.

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  13. CHECK FLOOR WIRE (CENTER AIRBAG SENSOR - SIDE AIRBAG SENSOR LH) 
    Fig 5: Identifying L20 And L10 Connector Terminal
    GTY164607Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      L20-4 (BBL+) - Body ground Ignition switch ON Below 1 V
      L20-3 (BBL-) - Body ground Ignition switch ON Below 1 V
    4. Turn the ignition switch to OFF.
    5. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    6. Using a service wire, connect terminals 8 (BBD+) and 15 (BBD-) of connector B.
      NOTE:

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

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

      Standard resistance

      Tester Connection Condition Specified Condition
      L20-4 (BBL+) - L20-3 (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
      L20-4 (BBL+) - L20-3 (BBL-) Always 1 MΩ or higher
      L20-4 (BBL+) - Body ground Always 1 MΩ or higher
      L20-3 (BBL-) - Body ground Always 1 MΩ or higher

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  14. CHECK CONNECTION OF CONNECTOR 
    1. Check that the connector is properly connected to the rear airbag sensor LH.

      OK

      The connector is properly connected.

    NG → CONNECT CONNECTORS PROPERLY 

    OK: Go to next step 

  15. CHECK CONNECTORS 
    1. Disconnect the connectors from the side airbag sensor LH and rear airbag sensor LH.
    2. Check that the connector (on the rear airbag sensor LH side) is not damaged.

      OK

      The connector is not deformed or damaged.

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  16. CHECK FLOOR WIRE (SIDE AIRBAG SENSOR LH - REAR AIRBAG SENSOR LH) 
    Fig 6: Identifying L18 And L20 Connector Terminals
    GTY164081Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    2. Turn the ignition switch to ON.
    3. Measure the voltage according to the value(s) in the table below.

      Standard voltage

      Tester Connection Switch Condition Specified Condition
      L20-1 (BCL+) - Body ground Ignition switch ON Below 1 V
      L20-2 (BCL-) - Body ground Ignition switch ON Below 1 V
    4. Turn the ignition switch to OFF.
    5. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    6. Using a service wire, connect terminals 2 (BCL+) and 1 (BCL-) of connector C.
      NOTE:

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

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

      Standard resistance

      Tester Connection Condition Specified Condition
      L20-1 (BCL+) - L20-2 (BCL-) Always Below 1 Ω
    8. Disconnect the service wire from connector C.
    9. Measure the resistance according to the value(s) in the table below.

      Standard resistance

      Tester Connection Condition Specified Condition
      L20-1 (BCL+) - L20-2 (BCL-) Always 1 MΩ or higher
      L20-1 (BCL+) - Body ground Always 1 MΩ or higher
      L20-2 (BCL-) - Body ground Always 1 MΩ or higher

    NG → REPLACE FLOOR WIRE 

    OK: Go to next step 

  17. CHECK SIDE AIRBAG SENSOR LH 
    Fig 7: Identifying Side Airbag Sensor RH
    GTY164639Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Interchange the side airbag sensor RH with LH and connect the connectors to them.
    2. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    5. Turn the ignition switch to OFF.
    6. Turn the ignition switch to ON, and wait for at least 90 seconds.
    7. Check for DTCs. Refer to DTC CHECK / CLEAR .
      RESULT

      Result Proceed to
      DTC B1628 or B1648 is output A
      DTC B1623, B1628, B1643 and B1648 are not output B
      DTC B1623 or B1643 is output C
    8. Turn the ignition switch to OFF.
    9. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    10. Return the side airbag sensor RH and LH to their original position and connect the connectors to them.

    B → See step   27 

    A → See step   26 

    C: Go to next step 

  18. CHECK REAR AIRBAG SENSOR LH 
    Fig 8: Identifying Rear Airbag Sensor RH
    GTY133962Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Interchange the rear airbag sensor RH with LH and connect the connectors to them.
    2. Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
    3. Turn the ignition switch to ON, and wait for at least 60 seconds.
    4. Clear the DTCs stored in the memory. Refer to DTC CHECK / CLEAR .
    5. Turn the ignition switch to OFF.
    6. Turn the ignition switch to ON, and wait for at least 90 seconds.
    7. Check for DTCs. Refer to DTC CHECK / CLEAR .
      RESULT

      Result Proceed to
      DTC B1623 or B1643 is output A
      DTC B1628 or B1648 is output B
      DTC B1623, B1628, B1643 and B1648 are not output C

      HINT: 

      Codes other than DTC B1623, B1628, B1643 and B1648 may be output at this time, but they are not related to this check.

    8. Turn the ignition switch to OFF.
    9. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
    10. Return the rear airbag sensor RH and LH to their original position and connect the connectors to them.

    B → See step   29 

    A → See step   28 

    C → See step   23 

  19. GO TO DTC B1622. Refer to  DTC B1620/21: Driver Side - Side Airbag Sensor Circuit Malfunction; DTC B1622/81: Lost Communication with Driver Side - Side Airbag Sensor Assembly; DTC B1625/22: Front Passenger Side - Side Airbag Sensor Circuit Malfunction; DTC B1627/82: Lost Communication with Front Passenger Side - Side Airbag Sensor Assembly  
  20. GO TO DTC B1632. Refer to  DTC B1632/81: Lost Communication with Driver Side Rear Airbag Sensor; DTC B1633/81: Driver Side Rear Airbag Sensor Initialization Incomplete; DTC B1637/82: Lost Communication with Passenger Side Rear Airbag Sensor; DTC B1638/82: Passenger Side Rear Airbag Sensor Initialization Incomplete  
  21. USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM 
  22. REPLACE SIDE AIRBAG SENSOR ASSEMBLY RH. Refer to  REMOVAL 
  23. USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM 
  24. REPLACE REAR AIRBAG SENSOR RH. Refer to  REMOVAL 
  25. REPLACE CENTER AIRBAG SENSOR ASSEMBLY. Refer to  REMOVAL 
  26. REPLACE SIDE AIRBAG SENSOR ASSEMBLY LH. Refer to  REMOVAL 
  27. USE SIMULATION METHOD TO CHECK. Refer to  DIAGNOSIS SYSTEM 
  28. REPLACE CENTER AIRBAG SENSOR ASSEMBLY. Refer to  REMOVAL 
  29. REPLACE REAR AIRBAG SENSOR LH. Refer to  REMOVAL 
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