AIRBAG SYSTEM SRS Warning Light Remains ON

DESCRIPTION

The SRS warning light is located in the combination meter assembly.

When the SRS is normal, the SRS warning light comes on for approximately 6 seconds after the power switch is turned from off on (IG), and then goes off automatically.

If there is a malfunction in the SRS, the SRS warning light comes on to inform the driver of a problem.

When terminals TC and CG of the DLC3 are connected, DTCs are output by the blinking of the SRS warning light.

The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the airbag ECU assembly in case the source voltage drops.

When the auxiliary battery voltage drops, the voltage-increase circuit (DC-DC converter) functions to increase the voltage of the SRS to normal voltage.

A malfunction in this circuit is not recorded in the airbag ECU assembly. The SRS warning light automatically goes off when the source voltage returns to normal.

The signal to illuminate the SRS warning light is transmitted from the airbag ECU assembly to the combination meter assembly through the CAN communication system.

WIRING DIAGRAM

B004VXFE25

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

  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • When replacing the combination meter assembly, always replace it with a new one. If a combination meter assembly which was installed to another vehicle is used, the information stored in it will not match the information from the vehicle and a DTC may be stored.

PROCEDURE


  1. CHECK SRS WARNING LIGHT OPERATION


    1. Turn the power switch on (IG) and check the SRS warning light condition.

      Tech Tips

      The primary check is performed for approximately 6 seconds after the power switch is turned on (IG).

      Result
      Result Proceed to
      After the primary check period, the SRS warning light remains on. A
      After the primary check period, the SRS warning light goes off and comes on again. B

    B
    A
  2. CHECK AUXILIARY BATTERY


    1. Measure the auxiliary battery voltage with the power switch off.

      Standard voltage
      11 to 14 V

      Tech Tips

      It may be possible to tell whether the auxiliary battery is discharged by operating the horn.

      If the voltage is below 11 V, recharge or replace the auxiliary battery before proceeding to the next step.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  3. CHECK CONNECTOR


    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 connector is properly connected to the airbag ECU assembly.

      OK
      The connector is properly connected.

      Tech Tips

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

    4. Disconnect the connector from the airbag ECU assembly.

    5. Check that the terminals of the connector are not deformed or damaged.

      OK
      The terminals are not deformed or damaged.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  4. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - BATTERY AND BODY GROUND)


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

    2. Turn the power switch on (IG).

    3. Operate all components of the electrical systems (defogger, wipers, headlights, heater blower, etc.).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      G11-36 (IG2) - Body ground Power switch on (IG) 8 to 16 V
    5. Turn the power switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G11-33 (E1) - Body ground Always Below 1 Ω
      G11-32 (E2) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  5. CHECK SRS WARNING LIGHT (SHORT TO GROUND)


    1. Turn the power switch on (IG) and check the SRS warning light condition.

      OK
      After the primary check period, the SRS warning light turns off for approximately 10 seconds and then turns back on.

      Tech Tips

      The primary check period is approximately 6 seconds after the power switch is turned on (IG).

      Result
      Proceed to
      OK
      NG

    OK
    NG
  6. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication DTC is output.

      Click here

      Result
      Proceed to
      DTCs are output
      DTC is not output

    DTCs are output
    DTC is not output
  7. CHECK AUXILIARY BATTERY


    1. Measure the auxiliary battery voltage with the power switch off.

      Standard voltage
      11 to 14 V

      Tech Tips

      It may be possible to tell whether the auxiliary battery is discharged by operating the horn.

      If the voltage is below 11 V, recharge or replace the auxiliary battery before proceeding to the next step.

      Result
      Proceed to
      OK
      NG

    NG
    OK
  8. CHECK CONNECTOR


    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 connector is properly connected to the airbag ECU assembly.

      OK
      The connector is properly connected.

      Tech Tips

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

    4. Disconnect the connector from the airbag ECU assembly.

    5. Check that the terminals of the connector are not deformed or damaged.

      OK
      The terminals are not deformed or damaged.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  9. CHECK HARNESS AND CONNECTOR (AIRBAG ECU ASSEMBLY - BATTERY AND BODY GROUND)


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

    2. Turn the power switch on (IG).

    3. Operate all components of the electrical systems (defogger, wipers, headlights, heater blower, etc.).

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      G11-36 (IG2) - Body ground Power switch on (IG) 8 to 16 V
    5. Turn the power switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      G11-33 (E1) - Body ground Always Below 1 Ω
      G11-32 (E2) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  10. CHECK CONNECTOR


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

    2. Check that the connector is properly connected to the combination meter assembly.

      OK
      The connector is properly connected.

      Tech Tips

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

    3. Disconnect the connector from the combination meter assembly.

    4. Check that the terminals of the connector are not deformed or damaged.

      OK
      The terminals are not deformed or damaged.
      Result
      Proceed to
      OK
      NG

    NG
    OK
  11. CHECK HARNESS AND CONNECTOR (COMBINATION METER ASSEMBLY - BATTERY AND BODY GROUND)


    1. 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
      G34-21 (IG+) - Body ground Power switch on (IG) 11 to 14 V
      G34-22 (B) - Body ground Power switch off 11 to 14 V
    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      G34-31 (ES) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG
    OK
  12. CHECK SRS WARNING LIGHT


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

    2. Connect the connector to the combination meter assembly.

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

    4. Turn the power switch on (IG) and check the SRS warning light condition.

      OK
      After the primary check period, the SRS warning light turns off for approximately 10 seconds and then turns back on.

      Tech Tips

      The primary check period is approximately 6 seconds after the power switch is turned on (IG).

      Result
      Proceed to
      OK
      NG

    OK
    NG