LIGHTING SYSTEM Headlight Relay Circuit

DESCRIPTION

The headlight relay is turned on by operating the headlight switch.

WIRING DIAGRAM

A0163C2E02

INSPECTION PROCEDURE

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER


    1. Connect the intelligent tester to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the intelligent tester on.

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

    5. Check the operation.

      Body (Main Body ECU RH)
      Tester Display Test Part Control Range Diagnostic Note
      Headlight Relay Headlight relay ON/OFF -
      OK
      Headlight assembly (low) illuminates.

    NG

    INSPECT FUSE (H-LP L LWR, H-LP R LWR) Click here

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  2. INSPECT FUSE (H-LP L LWR, H-LP R LWR)


    1. Remove the H-LP L LWR fuse from the No. 2 engine room relay block .

    2. Remove the H-LP R LWR fuse from the No. 2 engine room relay block .

    3. Measure the resistance of the fuses.

      Standard Resistance
      Below 1 Ω

    NG

    REPLACE FUSE

    OK

  3. INSPECT HEAD LP RELAY


    1. A0161ULE01

      Remove the HEAD LP relay from the engine room No. 1 relay block.

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

      Standard Resistance
      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5

      Below 1 Ω

      (When battery voltage is applied to terminals 1 and 2)

    NG

    REPLACE HEAD LP RELAY

    OK

  4. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU RH - BATTERY)


    1. A015ZD3E07

      Disconnect the RL main body ECU RH connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      RL-7 (HRLY) - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (HEADLIGHT (LOW LH OR LOW RH) - BATTERY AND BODY GROUND)


    1. A015YZEE17

      Check the wire harness between the headlight (Low LH) and battery, and the headlight (Low LH) and body ground.


      1. Disconnect the B12 headlight connector.

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        B12-17 (LO) - Body ground Turn the light control switch to the ON (HEAD) position. 11 to 14 V

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        B12-16 (E) - Body ground Always Below 1 Ω
    2. A015YZEE18

      Check the wire harness between the headlight (Low RH) and battery, and the headlight (Low RH) and body ground.


      1. Disconnect the B2 headlight connector.

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        B2-17 (LO) - Body ground Turn the light control switch to the ON (HEAD) position. 11 to 14 V

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        B2-16 (E) - Body ground Always Below 1 Ω

    NG

    CHECK HARNESS AND CONNECTOR (HEADLIGHT (LOW LH OR LOW RH) - HEAD LP RELAY) Click here

    OK

    REPLACE HEADLIGHT ASSEMBLY (LOW LH OR LOW RH) Click here

  6. CHECK HARNESS AND CONNECTOR (HEADLIGHT (LOW LH OR LOW RH) - HEAD LP RELAY)


    1. A015YKCE01

      Check the harness and the connectors between the headlight (Low LH or Low RH) and the HEAD LP relay.


      1. Disconnect the B12 headlight connector.

      2. Remove the HEAD LP relay from the No. 1 engine room relay block.

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

        Standard Resistance (Check for open)
        Headlight Assembly Tester Connection Specified Condition
        LH B12-17 (LO) - HEAD LP relay terminal (3) Below 1 Ω
        RH B2-17 (LO) - HEAD LP relay terminal (3) Below 1 Ω
        Standard Resistance (Check for short)
        Headlight Assembly Tester Connection Specified Condition
        LH B12-17 (LO) or HEAD LP relay terminal (3) - Body ground 10 kΩ or higher
        RH B2-17 (LO) or HEAD LP relay terminal (3) - Body ground 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH)