LIGHTING SYSTEM IG Signal Circuit

DESCRIPTION

This circuit detects whether the engine switch is on (IG) or off, and sends this information to the main body ECU (multiplex network body ECU).

WIRING DIAGRAM

B006Q1HE09

CAUTION / NOTICE / HINT

Note


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

  • If the main body ECU (multiplex network body ECU) is replaced, refer to the Service Bulletin.

  • As the door control battery is installed between the vehicle battery and main body ECU (multiplex network body ECU), first perform the inspections in On-vehicle Inspection to confirm that there are no malfunctions in the power source circuit for the main body ECU (multiplex network body ECU) before performing this troubleshooting procedure.

  • First, check for smart entry and start system (for Start Function) DTCs, and after confirming that there is no malfunction, proceed with troubleshooting.

    Click here

PROCEDURE


  1. READ VALUE USING GTS (IG SW)


    1. Using the GTS, read the Data List.

      Click here


      Body Electrical > Main Body > Data List
      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      IG SW Engine switch on (IG) signal ON or OFF

      ON: Engine switch on (IG)

      OFF: Engine switch off

      		 "OFF" is also displayed for this item when the engine switch is on (ACC).

      Body Electrical > Main Body > Data List
      Tester Display
      IG SW
      OK
      The display is as specified in the normal condition column.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  2. CHECK HARNESS AND CONNECTOR (JUNCTION BLOCK ASSEMBLY LH - BATTERY AND BODY GROUND)


    1. B006OTZC03
      *a

      Front view of wire harness connector

      (to Junction Block Assembly LH)

      Disconnect the junction block assembly LH connectors.

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

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      4K-1 - Body ground Always 11 to 14 V
      4F-16 - Body ground Engine switch on (IG) 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      4D-3 - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  3. CHECK HARNESS AND CONNECTOR (JUNCTION BLOCK ASSEMBLY LH CIRCUIT)


    1. Disconnect the 4A and 4D junction block assembly LHconnectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      4A-35 - 4D-22 Always Below 1 Ω
      4A-35 or 4D-22 - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT JUNCTION BLOCK ASSEMBLY LH (IG1 NO. 1 RELAY)


    1. B006LXGC05
      *a

      Component without harness connected

      (Junction Block Assembly LH)

      Remove the junction block assembly LH.

      Click here

    2. Remove the main body ECU (multiplex network body ECU) from the junction block assembly LH.

      Click here

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      4D-22 - A-32 (IG) Always Below 1 Ω
      4K-1 - 4A-35 Not connected 10 kΩ or higher
      4K-1 - 4A-35 Battery voltage applied between terminals 4F-16 and 4D-3 Below 1 Ω
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    NG

    REPLACE JUNCTION BLOCK ASSEMBLY LH Click here