AIRBAG SYSTEM, Diagnostic DTC:B1855/63, B1856/63, B1857/63, B1858/63

DTC Code DTC Name
B1855/63 Short in Rear Side Squib LH Circuit
B1856/63 Open in Rear Side Squib LH Circuit
B1857/63 Short to GND in Rear Side Squib LH Circuit
B1858/63 Short to B+ in Rear Side Squib LH Circuit

DESCRIPTION

The rear side squib LH circuit consists of the center airbag sensor assembly and the rear seat side airbag LH.

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

These DTCs are recorded when a malfunction is detected in the rear side squib LH circuit.

DTC Code Detection Condition Trouble Area
B1855/63

One of the following conditions is met:


  • The center airbag sensor assembly receives a line short circuit signal 5 times in the rear side squib LH circuit during the primary check.

  • Rear side squib LH malfunction

  • Center airbag sensor assembly malfunction

  • Rear No. 2 seat wire

  • No. 2 floor wire

  • Rear seat side airbag assembly LH (Rear side squib LH)

  • Center airbag sensor assembly
B1856/63

One of the following conditions is met:


  • The center airbag sensor assembly receives an open circuit signal in the rear side squib LH circuit for 2 seconds.

  • Rear side squib LH malfunction

  • Center airbag sensor assembly malfunction

  • Rear No. 2 seat wire

  • No. 2 floor wire

  • Rear seat side airbag assembly LH (Rear side squib LH)

  • Center airbag sensor assembly
B1857/63

One of the following conditions is met:


  • The center airbag sensor assembly receives a short circuit to ground signal in the rear side squib LH circuit for 0.5 seconds.

  • Rear side squib LH malfunction

  • Center airbag sensor assembly malfunction

  • Rear No. 2 seat wire

  • No.2 floor wire

  • Rear seat side airbag assembly LH (Rear side squib LH)

  • Center airbag sensor assembly
B1858/63

One of the following conditions is met:


  • The center airbag sensor assembly receives a short circuit to B+ signal in the rear side squib LH circuit for 0.5 seconds.

  • Rear side squib LH malfunction

  • Center airbag sensor assembly malfunction

  • Rear No. 2 seat wire

  • No. 2 floor wire

  • Rear seat side airbag assembly LH (Rear side squib LH)

  • Center airbag sensor assembly

WIRING DIAGRAM

A000X57E42
*a Sf2
*b Rear Side Squib LH
*c Center Airbag Sensor Assembly

CAUTION / NOTICE / HINT

Note


  • After turning the power switch OFF, waiting time may be required before disconnecting the cable from the negative (-) auxiliary battery terminal. Therefore, make sure to read the disconnecting the cable from the negative (-) auxiliary battery terminal notices before proceeding with work Click here.

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

Tech Tips


  • Change the intelligent tester to the "check mode" (signal check) with the intelligent tester Click here.

  • After selecting the "check mode" (signal check), perform the simulation method by wiggling each connector of the airbag system or driving the vehicle on various types of roads Click here.

PROCEDURE


  1. CHECK REAR SEAT SIDE AIRBAG LH (REAR SIDE SQUIB LH)

    A000Y7JE02

    1. Turn the power switch OFF.

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

    3. Disconnect the connector from the rear seat side airbag LH.

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

      CAUTION:

      Never connect the tester to the rear seat side airbag LH (rear side squib LH) 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 negative (-) terminal cable to the auxiliary battery, and wait for at least 2 seconds.

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

    7. Clear the DTCs Click here.

    8. Turn the power switch OFF.

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

    10. Check for DTCs Click here.

      OK
      DTC B1855, B1856, B1857 or B1858 is not output.

      Tech Tips

      Codes other than DTC B1855, B1856, B1857 and B1858 may be output at this time, but they are not related to this check.

      Result
      Result Proceed to
      OK: for Fixed seat type A
      OK: for Power seat B
      OK: for Ottoman C
      NG D

    A

    REPLACE REAR SEAT SIDE AIRBAG ASSEMBLY LH Click here

    B

    REPLACE REAR SEAT SIDE AIRBAG ASSEMBLY LH Click here

    C

    REPLACE REAR SEAT SIDE AIRBAG ASSEMBLY LH Click here

    D

  2. CHECK NO. 2 FLOOR WIRE (REAR SIDE SQUIB LH CIRCUIT)

    A000V2CE03

    1. Turn the power switch OFF.

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

    3. Disconnect SST from connector E.

    4. Disconnect the connectors from the center airbag sensor assembly.

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

    6. Turn the power switch ON (IG).

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      f35-1 (SRL+) - Body ground Power switch ON (IG) Below 1 V
      f35-2 (SRL-) - Body ground Power switch ON (IG) Below 1 V

    8. Turn the power switch OFF.

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      f35-1 (SRL+) - f35-2 (SRL-) Always Below 1 Ω

    11. Release the activation prevention mechanism built into connector B Click here.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      f35-1 (SRL+) - f35-2 (SRL-) Always 1 MΩ or higher
      f35-1 (SRL+) - Body ground Always 1 MΩ or higher
      f35-2 (SRL-) - Body ground Always 1 MΩ or higher

    NG

    CHECK REAR SEAT WIRE LH Click here

    OK

  3. CHECK CENTER AIRBAG SENSOR ASSEMBLY

    A000WMOE06
    *1 Rear Side Squib LH
    *2 Center Airbag Sensor Assembly

    1. Connect the connectors to the rear seat side airbag LH and the center airbag sensor assembly.

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

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

    4. Clear the DTCs Click here.

    5. Turn the power switch OFF.

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

    7. Check for DTCs Click here.

      OK
      DTC B1855, B1856, B1857 or B1858 is not output.

      Tech Tips

      Codes other than DTC B1855, B1856, B1857 and B1858 may be output at this time, but they are not related to this check.


    OK

    USE SIMULATION METHOD TO CHECK Click here

    NG

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY Click here

  4. CHECK REAR SEAT WIRE LH

    A000UVFE02

    1. Disconnect the No. 2 floor wire connector from the rear seat wire LH.

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

    3. Turn the power switch ON (IG).

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

      Standard voltage
      Tester Connection Switch Condition Specified Condition
      f35-1 (SRL+) - Body ground Power switch ON (IG) Below 1 V
      f35-2 (SRL-) - Body ground Power switch ON (IG) Below 1 V

    5. Turn the power switch OFF.

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

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

      Standard resistance
      Tester Connection Condition Specified Condition
      f35-1 (SRL+) - f35-2 (SRL-) Always Below 1 Ω

    8. Release the activation prevention mechanism built into connector D Click here.

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

      Standard resistance
      Tester Connection Condition Specified Condition
      f35-1 (SRL+) - f35-2 (SRL-) Always 1 MΩ or higher
      f35-1 (SRL+) - Body ground Always 1 MΩ or higher
      f35-2 (SRL-) - Body ground Always 1 MΩ or higher

    OK

    REPLACE NO. 2 FLOOR WIRE

    NG

    REPLACE REAR SEAT WIRE LH