AIRBAG SYSTEM Diagnosis Circuit

DESCRIPTION

DTC output mode is set by connecting terminals TC and CG of the DLC3.

DTCs are output by the blinking of the SRS warning light.

Tech Tips


  • When each warning light stays blinking, a ground short in the wiring of terminal TC of the DLC3 or an internal ground short in each ECU is suspected.

  • A DTC output mode signal is transmitted through the CAN communication system to each ECU including the center airbag sensor. Thus, when all systems do not enter DTC output mode, there may be an ECM malfunction.

WIRING DIAGRAM

B001WNGE10
B001WNGE11
B001WNGE08
for 3UR-FE
*a Center Airbag Sensor
*b CAN Line
B001WNGE06

CAUTION / NOTICE / HINT

Note


  • After turning the ignition switch off, waiting time may be required before disconnecting the cable from the battery terminal. Therefore, make sure to read the disconnecting the cable from the battery terminal notice before proceeding with work Click here.

  • When disconnecting the cable, some systems need to be initialized after the cable is reconnected Click here.

  • After replacing the center airbag sensor assembly, refer to initialization Click here.

PROCEDURE


  1. CHECK CAN COMMUNICATION SYSTEM


    1. Check if a CAN communication system DTC is output.

      Result
      Result Proceed to
      DTC is not output A
      DTC is output (for LHD with Central Gateway ECU) B
      DTC is output (for RHD with Central Gateway ECU) C
      DTC is output (for LHD without Central Gateway ECU) D
      DTC is output (for RHD without Central Gateway ECU) E

    B

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    C

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    D

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    E

    REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

    A

  2. CHECK HARNESS AND CONNECTOR (DLC3 - ECM)


    1. Turn the ignition switch off.

      B001WD8E02

    2. Disconnect the connector from the ECM.

    3. for LHD:


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

        Standard Resistance
        for 1GR-FE, Automatic Transmission
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A38-43 (TC) Always Below 1 Ω
        for 1GR-FE, Manual Transmission
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A38-16 (TC) Always Below 1 Ω
        for 1UR-FE
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A38-16 (TC) Always Below 1 Ω
        for 3UR-FE
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A38-43 (TC) Always Below 1 Ω
        for 1VD-FTV
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A38-27 (TC) Always Below 1 Ω

    4. for RHD:


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

        Standard Resistance
        for 1UR-FE
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A52-16 (TC) Always Below 1 Ω
        for 1VD-FTV
        Tester Connection Condition Specified Condition
        E22-13 (TC) - A52-27 (TC) Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (DLC3 - BODY GROUND)

    B001YXJE01
    *1 Front view of DLC3:

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      E22-4 (CG) - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (TC OF ECM - BODY GROUND)

    B001YARE01

    1. for LHD:


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

        Standard Resistance
        for 1GR-FE, Automatic Transmission
        Tester Connection Condition Specified Condition
        A38-43 (TC) - Body ground Always 1 MΩ or higher
        for 1GR-FE, Manual Transmission
        Tester Connection Condition Specified Condition
        A38-16 (TC) - Body ground Always 1 MΩ or higher
        for 1UR-FE
        Tester Connection Condition Specified Condition
        A38-16 (TC) - Body ground Always 1 MΩ or higher
        for 3UR-FE
        Tester Connection Condition Specified Condition
        A38-43 (TC) - Body ground Always 1 MΩ or higher
        for 1VD-FTV
        Tester Connection Condition Specified Condition
        A38-27 (TC) - Body ground Always 1 MΩ or higher

    2. for RHD:


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

        Standard Resistance
        for 1UR-FE
        Tester Connection Condition Specified Condition
        A52-16 (TC) - Body ground Always 1 MΩ or higher
        1VD-FTV
        Tester Connection Condition Specified Condition
        A52-27 (TC) - Body ground Always 1 MΩ or higher

    OK

    REPLACE CENTER AIRBAG SENSOR ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR OR EACH ECU