AIRBAG SYSTEM SRS Warning Light Remains ON

DESCRIPTION

The SRS warning light is located on 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 to 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, the DTC is displayed by blinking of the SRS warning light.

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

When the battery voltage drops, the voltage-increase circuit (DC-DC converter) functions to increase the voltage of the SRS to normal voltage. In addition, when the voltage drops, the SRS waning light will illuminate.

A malfunction in this circuit is not recorded in the center airbag sensor 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 center airbag sensor assembly to the combination meter assembly through the CAN communication system.

WIRING DIAGRAM

A01NCT5E02

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK SRS WARNING LIGHT OPERATION


    1. Check the SRS warning light operation approximately 6 seconds after the power switch is turned on (IG).

      Result
      SRS Warning Light Illumination Proceed to
      Remains on A
      Remains on after it goes off B

    B
    A
  2. CHECK BATTERY VOLTAGE


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

      Standard Voltage
      11 to 14 V

    NG
    OK
  3. CHECK CONNECTOR


    1. Turn the power switch off.

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

      Note

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

    3. Check that the connector is properly connected to the center airbag sensor assembly.

      OK
      The connector is properly connected.

      Tech Tips

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

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

    5. Check that the terminal of the connector is not damaged.

      OK
      The terminal is not deformed or damaged.

    NG
    OK
  4. CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BODY GROUND)


    1. A01ND7ME02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Center Airbag Sensor Assembly)

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

    2. Turn the power switch on (IG).

    3. Operate all components of the electrical system (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
      F29-21 (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
      F29-25 (E1) - Body ground Always Below 1 Ω
      F29-26 (E2) - Body ground Always Below 1 Ω

    NG
    OK
  5. CHECK SRS WARNING LIGHT


    1. Turn the power switch off.

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

      Note

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

    3. Disconnect the connector from the center airbag sensor assembly.

    4. Turn the power switch on (IG).

    5. Check the SRS warning light condition.

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

      Tech Tips

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


    NG
    OK
  6. CHECK CAN COMMUNICATION SYSTEM


    1. Use the intelligent tester to check if the CAN communication system is functioning normally.

      Tech Tips


      • Refer to Bus Check for the CAN communication system Click here.

      • The center airbag sensor assembly is connected to the CAN communication system. Therefore, before starting troubleshooting, make sure to check that there is no trouble in the CAN communication system.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output B

    B
    A
  7. CHECK BATTERY VOLTAGE


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

      Standard Voltage
      11 to 14 V

    NG
    OK
  8. CHECK CONNECTOR


    1. Turn the power switch off.

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

      Note

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

    3. Check that the connector is properly connected to the center airbag sensor assembly.

      OK
      The connector is properly connected.

      Tech Tips

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

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

    5. Check that the terminal of the connector is not damaged.

      OK
      The terminal is not deformed or damaged.

    NG
    OK
  9. CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BODY GROUND)


    1. A01ND7ME02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Center Airbag Sensor Assembly)

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

    2. Turn the power switch on (IG).

    3. Operate all components of the electrical system (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
      F29-21 (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
      F29-25 (E1) - Body ground Always Below 1 Ω
      F29-26 (E2) - Body ground Always Below 1 Ω

    NG
    OK
  10. CHECK CONNECTOR


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

      Note

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

    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 connected securely, reconnect the connector and proceed to the next inspection.

    3. Disconnect the connector from the combination meter assembly.

    4. Check that the terminal of the connector is not damaged.

      OK
      The terminal is not deformed or damaged.

    NG
    OK
  11. CHECK WIRE HARNESS (COMBINATION METER ASSEMBLY - BODY GROUND)


    1. A01NFIFE02
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Combination Meter Assembly)

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

    2. Turn the power switch on (IG).

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      F16-1 (IG+) - Body ground Power switch on (IG) 11 to 14 V
      F16-13 (B) - Body ground Power switch off 11 to 14 V
    4. Turn the power switch off.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      F16-6 (ES) - Body ground Always Below 1 Ω

    NG
    OK
  12. CHECK SRS WARNING LIGHT


    1. Connect the connector to the combination meter assembly.

    2. Turn the power switch off.

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

      Note

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

    4. Turn the power switch on (IG).

    5. Check the SRS warning light condition.

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

      Tech Tips

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


    NG
    OK