Airbag System (For Hatchback With Vsc/Separate Type Yaw Rate Sensor) Srs Warning Light Remains On

Vehicle Interior. Yaris. Ncp93, 131
Supplemental Restraint Systems. Yaris. Ncp93, 131

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

INSPECT BATTERY

CHECK CONNECTION OF CONNECTORS

CHECK HARNESS AND CONNECTOR (SOURCE VOLTAGE OF AIRBAG SENSOR ASSEMBLY)

CHECK HARNESS AND CONNECTOR (SOURCE VOLTAGE OF COMBINATION METER ASSEMBLY)

CHECK SRS WARNING LIGHT

AIRBAG SYSTEM (for Hatchback with VSC/Separate Type Yaw Rate Sensor) - SRS Warning Light Remains ON


DESCRIPTION

The SRS warning light is located on the combination meter assembly.
When the SRS condition is normal, the SRS warning light illuminates for approximately 6 seconds after the ignition switch is turned from off to ON, and then goes off automatically.
If there is a malfunction in the SRS, the SRS warning light illuminates or blinks to inform the driver of the problem. When terminals TC and CG of the DLC3 are connected, the SRS warning light blinks to indicate DTCs.
The airbag sensor assembly is equipped with a voltage-increase circuit (DC-DC converter) in case the source voltage decreases. When the battery voltage decreases, the voltage-increase circuit (DC-DC converter) boosts the SRS voltage up to the normal level.
Malfunctions relating to battery voltage decreases cause the SRS warning light to illuminate. However, no DTCs are recorded in the airbag sensor assembly. The SRS warning light goes off automatically when the source voltage returns to normal.
Signals to illuminate the SRS warning light are transmitted from the airbag sensor assembly to the combination meter assembly through the CAN communication system.

WIRING DIAGRAM


Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan).Airbag System (For Hatchback With Vsc/Separate Type Yaw Rate Sensor) Srs Warning Light Remains On


INSPECTION PROCEDURE

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.
1.CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

  1. Turn the ignition switch to ON.

  1. Check the DTCs (YARIS_NCP93 RM000001RSW02LX.html).

    OK:
    DTC is not output.


NG
GO TO CAN COMMUNICATION SYSTEM (YARIS_NCP93 RM000001RSO05UX.html)
OK


2.INSPECT BATTERY

  1. Measure the voltage of the battery.

    Standard Voltage:
    Tester Connection
    		Condition
    		Specified Condition
    Battery
    		Always
    		11 to 14 V


NG
CHECK AND REPLACE BATTERY OR CHARGING SYSTEM (YARIS_NCP93 RM000001GNJ010X.html)
OK


3.CHECK CONNECTION OF CONNECTORS

  1. Turn the ignition switch off.

  1. 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.

  1. Check that the connectors are properly connected to the airbag sensor assembly and combination meter assembly.

    OK:
    The connectors are properly connected.


NG
CONNECT CONNECTORS PROPERLY
OK


4.CHECK HARNESS AND CONNECTOR (SOURCE VOLTAGE OF AIRBAG SENSOR ASSEMBLY)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan).Airbag System (For Hatchback With Vsc/Separate Type Yaw Rate Sensor) Srs Warning Light Remains On

  1. Disconnect the connectors from the airbag sensor assembly.

  1. Connect the cable to the negative battery terminal, and wait for at least 2 seconds.

  1. Turn the ignition switch to ON.

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

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    D112-21 (IG2) -
    D112-25 (E1)
    		Ignition switch ON
    		11 to 14 V
    D112-21 (IG2) -
    D112-26 (E2)
    		Ignition switch ON
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Airbag Sensor Assembly)


NG
REPLACE HARNESS AND CONNECTOR
OK


5.CHECK HARNESS AND CONNECTOR (SOURCE VOLTAGE OF COMBINATION METER ASSEMBLY)


    Yaris. Ncp93, 131.Supplemental Restraint Systems.Airbag System (For Sedan).Airbag System (For Hatchback With Vsc/Separate Type Yaw Rate Sensor) Srs Warning Light Remains On

  1. 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.

  1. Disconnect the connector from the combination meter assembly.

  1. Connect the cable to the negative battery terminal, and wait for at least 2 seconds.

  1. Turn the ignition switch to ON.

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

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    D100-39 (IG+) -
    D100-21 (ET)
    		Ignition switch ON
    		11 to 14 V
    Text in Illustration
    *a
    		Front view of wire harness connector
    (to Combination Meter Assembly)


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


6.CHECK SRS WARNING LIGHT

  1. Turn the ignition switch off.

  1. 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.

  1. Connect the connector to the combination meter assembly.

  1. Connect the cable to the negative battery terminal, and wait for at least 2 seconds.

  1. Turn the ignition switch to ON.

  1. Check the SRS warning light condition.

    OK:
    The SRS warning light goes off after the primary check period and comes on again after approximately 10 seconds.
    HINT:
    The primary check period lasts for approximately 6 seconds after the ignition switch is turned to ON.


NG
REPLACE COMBINATION METER ASSEMBLY (YARIS_NCP93 RM0000035EJ00BX.html)
OK

REPLACE AIRBAG SENSOR ASSEMBLY (YARIS_NCP93 RM000000V6U02AX.html)