AIRBAG SYSTEM, Diagnostic DTC:B1845/61, B1846/61, B1847/61, B1848/61

DTC Code DTC Name
B1845/61 Short in Curtain Shield Squib LH 2nd Step Circuit
B1846/61 Open in Curtain Shield Squib LH 2nd Step Circuit
B1847/61 Short to GND in Curtain Shield Squib LH 2nd Step Circuit
B1848/61 Short to B+ in Curtain Shield Squib LH 2nd Step Circuit

DESCRIPTION

The curtain shield squib LH circuit consists of the airbag ECU assembly and curtain shield airbag assembly LH (2nd step).

The circuit instructs the SRS to deploy when deployment conditions are met.

These DTCs are stored when a malfunction is detected in the curtain shield squib LH circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1845/61 Short in Curtain Shield Squib LH 2nd Step Circuit

One of the following conditions is met:


  • The airbag ECU assembly detects a line short circuit signal 5 times in the curtain shield squib LH circuit during the primary check.

  • A curtain shield airbag assembly LH (2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Floor wire

  • Curtain shield airbag assembly LH (2nd step)

  • Airbag ECU assembly
B1846/61 Open in Curtain Shield Squib LH 2nd Step Circuit

One of the following conditions is met:


  • The airbag ECU assembly detects an open circuit signal in the curtain shield squib LH circuit for 2 seconds.

  • A curtain shield airbag assembly LH (2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Floor wire

  • Curtain shield airbag assembly LH (2nd step)

  • Airbag ECU assembly
B1847/61 Short to GND in Curtain Shield Squib LH 2nd Step Circuit

One of the following conditions is met:


  • The airbag ECU assembly detects a short circuit to ground signal in the curtain shield squib LH circuit for 0.5 seconds.

  • A curtain shield airbag assembly LH (2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Floor wire

  • Curtain shield airbag assembly LH (2nd step)

  • Airbag ECU assembly
B1848/61 Short to B+ in Curtain Shield Squib LH 2nd Step Circuit

One of the following conditions is met:


  • The airbag ECU assembly detects a short circuit to B+ signal in the curtain shield squib LH circuit for 0.5 seconds.

  • A curtain shield airbag assembly LH (2nd step) malfunction.

  • An airbag ECU assembly malfunction.

  • Floor wire

  • Curtain shield airbag assembly LH (2nd step)

  • Airbag ECU assembly

WIRING DIAGRAM

B006Q5SE78
*a Curtain Shield Airbag Assembly LH (2nd Step)
*b 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

  • After replacing the airbag ECU assembly, refer to initialization.

    Click here

Tech Tips

To perform the simulation method, enter check mode (signal check) with the GTS (Click here ), and then wiggle each connector of the airbag system or drive the vehicle on various types of road Click here.

PROCEDURE


  1. CHECK CURTAIN SHIELD AIRBAG ASSEMBLY LH (2ND STEP)


    1. B006N5GC06
      *1 Curtain Shield Airbag Assembly LH (2nd Step)
      *2 Airbag ECU Assembly
      *3 Connector C
      *4 SST
      *a

      Front view of wire harness connector

      (to Curtain Shield Airbag Assembly LH [2nd Step])

      Turn the engine switch off.

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

    3. Disconnect the connectors from the curtain shield airbag assembly LH (2nd step).

    4. Connect the white wire side of SST (resistance: 2.1 Ω) to connector C.

      CAUTION:

      Never connect the tester to the curtain shield airbag assembly LH (2nd step) for measurement, as this may lead to a serious injury due to airbag deployment.

      Note


      • Do not forcibly insert SST into the terminals of the connector when connecting SST.

      • Insert SST straight into the terminals of the connector.

      SST
      09843-18061

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

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

    7. Clear the DTCs.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    8. Turn the engine switch off.

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

    10. Check for DTCs.

      Click here


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1845/61, B1846/61, B1847/61 or B1848/61 is not output
      DTC B1845/61, B1846/61, B1847/61 or B1848/61 is output

      Tech Tips

      Codes other than DTC B1845/61, B1846/61, B1847/61 and B1848/61 may be output at this time, but they are not related to this check.

    11. Turn the engine switch off.

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

    13. Disconnect SST from connector C.


    DTC B1845/61, B1846/61, B1847/61 or B1848/61 is not output

    REPLACE CURTAIN SHIELD AIRBAG ASSEMBLY LH (2ND STEP) Click here

    DTC B1845/61, B1846/61, B1847/61 or B1848/61 is output

  2. CHECK CONNECTORS


    1. Disconnect the connectors from the airbag ECU assembly.

    2. B006NDDC02
      *1 Curtain Shield Airbag Assembly LH (2nd Step)
      *2 Floor Wire
      *3 Airbag ECU Assembly

      Check that the connectors (on the airbag ECU assembly side and curtain shield airbag assembly LH [2nd step] side) are not damaged.

      OK
      The lock button is not disengaged, and the claw of the lock is not deformed or damaged.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  3. CHECK FLOOR WIRE


    1. B006LDIC05
      *1 Curtain Shield Airbag Assembly LH (2nd Step)
      *2 Floor Wire
      *3 Airbag ECU Assembly
      *4 Connector C
      *a

      Front view of wire harness connector

      (to Curtain Shield Airbag Assembly LH [2nd Step])

      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
      K10-1 (B) - Body ground Engine switch on (IG) Below 1 V
      K10-2 (FP) - 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. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      K10-1 (B) - K10-2 (FP) Always Below 1 Ω

    7. Release the activation prevention mechanism built into connector B.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K10-1 (B) - K10-2 (FP) Always 1 MΩ or higher

    9. Restore the released activation prevention mechanism of connector B to its original condition.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      K10-1 (B) - Body ground Always 1 MΩ or higher
      K10-2 (FP) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE FLOOR WIRE

    OK

  4. CHECK DTC


    1. B006NT3C09
      *1 Curtain Shield Airbag Assembly LH (2nd Step)
      *2 Airbag ECU Assembly

      Connect the connectors to the curtain shield airbag assembly LH (2nd step) and airbag ECU assembly.

    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 B1845/61, B1846/61, B1847/61 or B1848/61 is not output
      DTC B1845/61, B1846/61, B1847/61 or B1848/61 is output

      Tech Tips

      Codes other than DTC B1845/61, B1846/61, B1847/61 and B1848/61 may be output at this time, but they are not related to this check.


    DTC B1845/61, B1846/61, B1847/61 or B1848/61 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1845/61, B1846/61, B1847/61 or B1848/61 is output

    REPLACE AIRBAG ECU ASSEMBLY w/ Navigation System: REPLACE AIRBAG ECU ASSEMBLY Click here
    REPLACE AIRBAG ECU ASSEMBLY w/o Navigation System: REPLACE AIRBAG ECU ASSEMBLY Click here