AIRBAG SYSTEM, Diagnostic DTC:B1651/33

DTC Code DTC Name
B1651/33 Manual Cut off Switch Trouble

DESCRIPTION

Tech Tips

"Manual cut off switch" refers to the airbag cutoff switch cylinder sub-assembly.

The airbag cutoff switch cylinder sub-assembly consists of the airbag ECU assembly and airbag cutoff switch cylinder sub-assembly.

The instrument panel passenger airbag assembly can be optionally deactivated via this circuit by turning the airbag cutoff switch cylinder sub-assembly to the "OFF" position.

If the instrument panel passenger airbag assembly is deactivated, the airbag cutoff switch cylinder sub-assembly comes on to inform the passengers.

DTC B1651/33 is stored when a malfunction is detected in the airbag cutoff switch cylinder sub-assembly circuit.

DTC No. Detection Item DTC Detection Condition Trouble Area
B1651/33 Manual Cut off Switch Trouble

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 airbag cutoff switch cylinder sub-assembly circuit for 2 seconds.

  • An airbag cutoff switch cylinder sub-assembly malfunction.

  • An airbag ECU assembly malfunction.

  • Instrument panel wire

  • Airbag cutoff switch cylinder sub-assembly

  • Airbag ECU assembly

WIRING DIAGRAM

B002KF3E03
*a Airbag Cutoff Switch Cylinder Sub-assembly
*b Airbag ECU 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

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

    Click here

Tech Tips

The 11 (MSW+) and 12 (MSW-) terminals in this circuit have an activation prevention mechanism. This mechanism can be used to check for an open circuit in the wire harness. In case of other checks (check for short, short to ground or short to B+), it is necessary to release this mechanism.

PROCEDURE


  1. CHECK CONNECTION OF CONNECTORS


    1. Turn the power switch off.

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

    3. Check that the connectors are properly connected to the airbag ECU assembly and airbag cutoff switch cylinder sub-assembly.

      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

  2. CHECK CONNECTORS


    1. Disconnect the connectors from the airbag ECU assembly and airbag cutoff switch cylinder sub-assembly.

    2. B002HD5C04
      *1 Airbag Cutoff Switch Cylinder Sub-assembly
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire

      Check that the connectors (on the airbag ECU assembly side and airbag cutoff switch cylinder sub-assembly 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 INSTRUMENT PANEL WIRE

    The connectors are not deformed or damaged

  3. CHECK INSTRUMENT PANEL WIRE


    1. B002I7IC01
      *1 Airbag Cutoff Switch Cylinder Sub-assembly
      *2 Airbag ECU Assembly
      *3 Connector C
      *4 Connector B
      *5 Instrument Panel Wire
      *a

      Front view of wire harness connector

      (to Airbag Cutoff Switch Cylinder Sub-assembly)
      *b

      Rear view of wire harness connector

      (to Airbag ECU Assembly)

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

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      I128-2 (PMC+) - Body ground Power switch on (IG) Below 1 V
      I128-1 (PMC-) - Body ground Power switch on (IG) Below 1 V

    4. Turn the power switch off.

    5. Disconnect the cable from the negative (-) auxiliary 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
      I128-2 (PMC+) - I128-1 (PMC-) 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
      I128-2 (PMC+) - I128-1 (PMC-) 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
      I128-2 (PMC+) - Body ground Always 1 MΩ or higher
      I128-1 (PMC-) - Body ground Always 1 MΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  4. INSPECT AIRBAG CUTOFF SWITCH CYLINDER SUB-ASSEMBLY


    1. Remove the airbag cutoff switch cylinder sub-assembly.

      Click here

    2. Inspect the airbag cutoff switch cylinder sub-assembly.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIRBAG CUTOFF SWITCH CYLINDER SUB-ASSEMBLY Click here

    OK

  5. CHECK DTC


    1. B002IBQC05
      *1 Airbag Cutoff Switch Cylinder Sub-assembly
      *2 Airbag ECU Assembly

      Connect the connectors to the airbag ECU assembly and airbag cutoff switch cylinder sub-assembly.

    2. Connect the cable to the negative (-) auxiliary battery terminal, 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 stored in memory.

      Click here


      Body Electrical > SRS Airbag > Clear DTCs

    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


      Body Electrical > SRS Airbag > Trouble Codes
      Result
      Proceed to
      DTC B1651/33 is not output
      DTC B1651/33 is output

      Tech Tips

      Codes other than DTC B1651/33 may be output at this time, but they are not related to this check.


    DTC B1651/33 is not output

    USE SIMULATION METHOD TO CHECK Click here

    DTC B1651/33 is output

    REPLACE AIRBAG ECU ASSEMBLY Click here