LIGHTING SYSTEM Low Beam Headlight Circuit

DTC Code DTC Name
Low Beam Headlight Circuit

DESCRIPTION

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

WIRING DIAGRAM

  1. for LED Headlight

    E259642E11

  2. for Halogen Headlight

    E259643E11

CAUTION / NOTICE / HINT

Note:

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

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

      Headlight Relay

      Headlight relay (Low beam headlights)

      ON/OFF

      -

      Body Electrical > Main Body > Active Test

      Tester Display

      Headlight Relay

      OK

      Headlight relay operates. (Low beam headlights illuminate.)

    Result

    Proceed to

    OK

    NG
    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    NG

  2. INSPECT H-LP RELAY

    1. Remove the H-LP relay from the engine room relay block and junction block assembly.

    2. E223988N04

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3 - 5

      Voltage not applied between terminals 1 and 2

      10 kΩ or higher

      3 - 5

      Voltage applied between terminals 1 and 2

      Below 1 Ω

    Result

    Proceed to

    OK

    NG
    NG

    REPLACE H-LP RELAY

    OK

  3. CHECK HARNESS AND CONNECTOR (H-LP-MAIN FUSE - H-LP RELAY)

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      Relay terminal 1 - Body ground

      Always

      11 to 14 V

      Relay terminal 5 - Body ground

      Always

      11 to 14 V

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (H-LP RELAY - HEADLIGHT ASSEMBLY LH AND HEADLIGHT ASSEMBLY RH)

    1. for LED Headlight (except Sedan):

      1. Disconnect the A70 headlight assembly LH connector.

      2. Disconnect the A73 headlight assembly RH connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        Relay terminal 3 - A70-4 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - A73-4 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - Body ground

        Always

        10 kΩ or higher

    2. for LED Headlight (for Sedan):

      1. Disconnect the A184 headlight assembly LH connector.

      2. Disconnect the A183 headlight assembly RH connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        Relay terminal 3 - A184-2 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - A183-2 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - Body ground

        Always

        10 kΩ or higher

    3. for Halogen Headlight (except Sedan):

      1. Disconnect the A70 headlight assembly LH connector.

      2. Disconnect the A73 headlight assembly RH connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        Relay terminal 3 - A70-4 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - A73-4 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - Body ground

        Always

        10 kΩ or higher

    4. for Halogen Headlight (for Sedan):

      1. Disconnect the A153 headlight assembly LH connector.

      2. Disconnect the A152 headlight assembly RH connector.

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

        Standard Resistance

        Tester Connection

        Condition

        Specified Condition

        Relay terminal 3 - A153-2 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - A152-2 (LO)

        Always

        Below 1 Ω

        Relay terminal 3 - Body ground

        Always

        10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (H-LP RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

    1. Disconnect the 3A instrument panel junction block assembly connector.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      Relay terminal 2 - 3A-35

      Always

      Below 1 Ω

      Relay terminal 2 - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  6. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    1. Remove the instrument panel junction block assembly.

      for LHD:Click here

      for RHD:Click here

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

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

      E259586C01

      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      -

      -

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3A-35 - MB-15 (HRLY)

      Always

      Below 1 Ω

      3A-35 - Body ground

      Always

      10 kΩ or higher

    Result

    Proceed to

    OK

    NG
    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    for LHD:Click here

    for RHD:Click here

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

    for LHD:Click here

    for RHD:Click here