LIGHTING SYSTEM High Beam Headlight Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the high beam headlights.

WIRING DIAGRAM

A002BQ8E01

CAUTION / NOTICE / HINT

Note


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

  • Check the operation of the low beam headlights. If the low beam headlights do not operate normally, refer to Problem Symptoms Table.

    Click here

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


    • *: w/ Smart Entry and Start System

  • 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.*

    Click here


    • *: for LHD

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON.

    3. Turn the GTS on.

    4. Enter the following menus: Body Electrical / Main Body / Active Test.

    5. Perform the Active Test according to the display on the GTS.


      Body Electrical > Main Body > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Head Light Hi High beam headlights OFF or ON -

      Body Electrical > Main Body > Active Test
      Tester Display
      Head Light Hi
      OK
      The high beam headlights illuminate.
      Result
      Proceed to
      OK
      NG

    OK

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

    NG

  2. CHECK SEMICONDUCTOR PWR INTEGRATION ECU


    1. Using a voltmeter, check the signal reading of the semiconductor pwr integration ECU.

      Click here

      OK
      Output signal reading is normal.
      Result
      Proceed to
      OK
      NG

    NG

    INSPECT SEMICONDUCTOR PWR INTEGRATION ECU (RESULTS OF SIGNAL READING CHECK) Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU POWER SOURCE AND BODY GROUND)

    A002CAVC08
    *a

    Component without semiconductor pwr integration ECU connected

    (No. 1 Engine Room Relay Block and No. 1 Junction Block Assembly)

    		 - -

    1. Remove the semiconductor pwr integration ECU from the No. 1 engine room relay block and No. 1 junction block assembly.

      Click here

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      1B-1 (BATT) - Body ground Always 11 to 14 V
      1A-1 (ALT) - Body ground Always 11 to 14 V

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1D-14 (GND1) - Body ground Always Below 1 Ω
      1G-5 (GND2) - Body ground Always Below 1 Ω
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (SEMICONDUCTOR PWR INTEGRATION ECU - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))


    1. Disconnect the F18 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      1D-2 (DIMS) - F18-24 (DIM) Always Below 1 Ω
      1D-2 (DIMS) or F18-24 (DIM) - Body ground Always 10 kΩ or higher
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK SEMICONDUCTOR PWR INTEGRATION ECU


    1. Replace the semiconductor pwr integration ECU with a new or known good one.

      Click here

    2. Check that the high beam headlights operate normally.

      OK
      The high beam headlights operate normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (SEMICONDUCTOR PWR INTEGRATION ECU WAS DEFECTIVE)

    NG

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