THEFT DETERRENT SYSTEM Ignition Switch Circuit

DESCRIPTION

The main body ECU determines the ignition switch position (OFF, ACC, ON) based on signals from the IG or ACC circuit.

WIRING DIAGRAM

A011BO0E01

INSPECTION PROCEDURE

Note

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

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

    5. According to the display on the intelligent tester, read the Data List.

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      IG SW Ignition switch ON signal/ON or OFF

      ON: Ignition switch is ON

      OFF: Ignition switch is off

      		 -
      ACC SW Ignition switch ACC signal/ON or OFF

      ON: Ignition switch is ACC

      OFF: Ignition switch is off

      		 -
      OK
      When the ignition switch is operated, the display changes as shown in the table.

    NG

    CHECK HARNESS AND CONNECTOR (BATTERY - INSTRUMENT PANEL JUNCTION BLOCK) Click here

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  2. CHECK HARNESS AND CONNECTOR (BATTERY - INSTRUMENT PANEL JUNCTION BLOCK)


    1. A011ABUE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Instrument Panel Junction Block)

      Disconnect the 3A junction block connector.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      3A-1 - Body ground Ignition switch ON 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. INSPECT IGNITION SWITCH ASSEMBLY


    1. A011BDVE01
      Text in Illustration
      *1

      Component without harness connected

      (Ignition Switch)

      Remove the ignition switch Click here.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      2 - 3 Ignition switch ON Below 1 Ω
      2 - 4
      3 - 4
      2 - 3 Ignition switch ACC Below 1 Ω

    NG

    REPLACE IGNITION SWITCH ASSEMBLY Click here

    OK

  4. CHECK HARNESS AND CONNECTOR (IGNITION SWITCH - INSTRUMENT PANEL JUNCTION BLOCK)


    1. Reinstall the ignition switch.

    2. A0119YCE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Instrument Panel Junction Block)
      *2

      Front view of wire harness connector

      (to Instrument Panel Junction Block)

      Disconnect the 3C and 3D junction block connector.

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

      Standard Resistance
      Tester Connection Switch Condition Specified Condition
      3C-23 - 3D-28 Ignition switch ON Below 1 Ω
      3D-28 - 3D-27 Ignition switch ACC Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (INSTRUMENT PANEL JUNCTION BLOCK - BODY GROUND)


    1. A0118MVE01
      Text in Illustration
      *1

      Front view of wire harness connector

      (to Instrument Panel Junction Block)

      Disconnect the 3C junction block connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      3C-10 - Body ground Always Below 1 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. REPLACE MAIN BODY ECU


    1. Temporarily replace the main body ECU with a new or normally functioning one Click here.


    NEXT

  7. READ VALUE USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the intelligent tester on.

    4. Enter the following menus: Body Electrical / Main Body / Data List.

    5. According to the display on the intelligent tester, read the Data List.

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      IG SW Ignition switch ON signal/ON or OFF

      ON: Ignition switch is ON

      OFF: Ignition switch is off

      		 -
      ACC SW Ignition switch ACC signal/ON or OFF

      ON: Ignition switch is ACC

      OFF: Ignition switch is off

      		 -
      OK
      When the ignition switch is operated, the display changes as shown in the table.

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK

    OK

    END (MAIN BODY ECU IS DEFECTIVE)