AIRBAG SYSTEM Trouble in Passenger Airbag ON/OFF Indicator

DESCRIPTION

This circuit detects the airbag cut off switch status.

The passenger airbag ON/OFF indicator comes on to inform the front passenger airbag status (activated or deactivated).

Tech Tips

Approximately 6 seconds after the ignition switch is turned ON, the passenger airbag ON/OFF indicator will indicate ON/OFF depending on the conditions listed below.

Airbag Cut Off Switch Passenger Airbag ON/OFF Indicator SRS Warning Light
ON Indicator OFF Indicator
ON position ON OFF OFF
OFF position OFF ON OFF
Switch failure OFF ON ON

WIRING DIAGRAM

A004H8QE01
*a Airbag Cut Off Switch
*b Airbag ECU Assembly

CAUTION / NOTICE / HINT

Tech Tips

Terminals D27-14 (MSW+) and D27-12 (MSW-) of the airbag ECU assembly 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+), this mechanism should be released.

PROCEDURE


  1. CHECK SRS WARNING LIGHT


    1. Turn the ignition switch ON, and check the SRS warning light condition.

      Tech Tips

      If this trouble occurs, the SRS warning light is off. If it is on, a DTC is stored. Troubleshoot for the stored DTC.

      OK
      After the primary check period, the SRS warning light goes off.

      Tech Tips

      The primary check period is approximately 6 seconds after the ignition switch is turned ON.


    NG

    GO TO DTC CHART Click here

    OK

  2. CHECK CONNECTORS


    1. Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

    3. Check that the connectors are properly connected to the airbag ECU assembly and airbag cut off switch.

      OK
      The connectors are properly connected.

      Tech Tips

      If the connector is not connected securely, reconnect the connector and proceed to the next inspection.

    4. Disconnect the connectors from the airbag ECU assembly and airbag cut off switch.

    5. Check that the terminals of the connectors are not damaged.

      OK
      The terminals are not deformed or damaged.

    6. Check that the short spring for the instrument panel wire connector with the activation prevention mechanism is not deformed or damaged.

      OK
      The short spring is not deformed or damaged.

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  3. CHECK INSTRUMENT PANEL WIRE (OPEN)


    1. Using a service wire, connect terminals 12 (MSW-) and 14 (MSW+) of connector B.

      Note

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

    2. A004KQEE02
      Text in Illustration
      *1 Airbag Cut Off Switch
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire
      *a

      Front view of wire harness connector

      (to Airbag ECU Assembly)
      *b

      Front view of wire harness connector

      (to Airbag Cut Off Switch)

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D37-2 (MSW+) - D37-1 (MSW-) Always Below 1 Ω

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  4. CHECK INSTRUMENT PANEL WIRE (SHORT)


    1. A004ICGE02
      Text in Illustration
      *1 Airbag Cut Off Switch
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire
      *a

      Front view of wire harness connector

      (to Airbag Cut Off Switch)

      Disconnect the service wire from connector B.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      D37-2 (MSW+) - D37-1 (MSW-) Always 1 MΩ or higher

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  5. CHECK INSTRUMENT PANEL WIRE (SHORT TO B+)


    1. A004ICGE02
      Text in Illustration
      *1 Airbag Cut Off Switch
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire
      *a

      Front view of wire harness connector

      (to Airbag Cut Off Switch)

      Connect the cable to the negative (-) battery terminal.

    2. Turn the ignition switch to ON.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      D37-1 (MSW-) - Body ground Ignition switch ON Below 1 V
      D37-2 (MSW+) - Body ground Ignition switch ON Below 1 V

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  6. CHECK INSTRUMENT PANEL WIRE (SHORT TO GROUND)


    1. A004ICGE02
      Text in Illustration
      *1 Airbag Cut Off Switch
      *2 Airbag ECU Assembly
      *3 Instrument Panel Wire
      *a

      Front view of wire harness connector

      (to Airbag Cut Off Switch)

      Turn the ignition switch off.

    2. Disconnect the cable from the negative (-) battery terminal.

      CAUTION:

      Wait at least 90 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      D37-1 (MSW-) - Body ground Always 1 MΩ or higher
      D37-2 (MSW+) - Body ground Always 1 MΩ or higher

    NG

    REPLACE INSTRUMENT PANEL WIRE

    OK

  7. CHECK AIRBAG CUT OFF SWITCH


    1. A004H3UE01
      Text in Illustration
      *a

      Component without harness connected

      (Airbag Cut Off Switch)

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      2 (MSW+) - 1 (MSW-) Cut off switch in ON 100 Ω
      Cut off switch in OFF 400 Ω

    OK

    REPLACE AIRBAG ECU ASSEMBLY Click here

    NG

    REPLACE AIRBAG CUT OFF SWITCH Click here