LIGHTING SYSTEM Low Beam Headlight Circuit

DESCRIPTION

The main body ECU controls the low beam headlights via the H-LP/US-DRL relay.

WIRING DIAGRAM


  1. except 2ZR-FE

    B0045OOE08

  2. for 2ZR-FE

    B0045OOE07

CAUTION / NOTICE / HINT

Note

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

PROCEDURE


  1. PERFORM ACTIVE TEST USING GTS (HEADLIGHT RELAY)


    1. Connect the GTS to the DLC3.

    2. Turn the ignition switch to ON (IG).

    3. Turn the GTS on.

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

    5. According to the display on the GTS, perform the Active Test.

      Main Body
      Tester Display Test Part Control Range Diagnostic Note
      Headlight Relay Headlight relay OFF or ON -
      OK
      Headlight relay operates (Low beam headlights illuminate).

    OK

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

    NG

  2. INSPECT HEADLIGHT RELAY (H-LP/US-DRL RELAY OR H-LP RELAY)


    1. except 2ZR-FE


      1. Remove the headlight relay (H-LP/US-DRL relay).

      2. Inspect the headlight relay (H-LP/US-DRL relay).

        Click here

    2. for 2ZR-FE


      1. Remove the headlight relay (H-LP relay).

      2. Inspect the headlight relay (H-LP relay).

        Click here


    NG

    REPLACE HEADLIGHT RELAY (H-LP/US-DRL RELAY)

    OK

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY(H-LP/US-DRL) - BATTERY)


    1. except 2ZR-FE


      1. Remove the headlight relay (H-LP/US-DRL relay) from the No. 2 engine room relay block.

      2. B0045NDC04
        *1 No. 2 Engine Room Relay Block
        *2 Headlight Relay (H-LP/US-DRL Relay) Holder

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        H-LP/US-DRL-1 - Body ground Always 11 to 14 V
        H-LP/US-DRL-3 - Body ground Always 11 to 14 V

    2. for 2ZR-FE


      1. Remove the headlight relay (H-LP relay) from the No. 2 engine room relay block.

      2. B0045NDC04
        *1 No. 2 Engine Room Relay Block
        *2 Headlight Relay (H-LP Relay) Holder

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

        Standard Voltage
        Tester Connection Condition Specified Condition
        H-LP-1 - Body ground Always 11 to 14 V
        H-LP-3 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)


    1. except 2ZR-FE


      1. Remove the headlight relay (H-LP/US-DRL relay) from the No. 2 engine room relay block.

      2. Disconnect the 3C instrument panel junction block assembly connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        H-LP/US-DRL-2 - 3C-18 Always Below 1 Ω
        H-LP/US-DRL-2 or 3C-18 - Body ground Always 10 kΩ or higher

    2. for 2ZR-FE


      1. Remove the headlight relay (H-LP relay) from the No. 2 engine room relay block.

      2. Disconnect the 3C instrument panel junction block assembly connector.

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

        Standard Resistance
        Tester Connection Condition Specified Condition
        H-LP-2 - 3C-18 Always Below 1 Ω
        H-LP-2 or 3C-18 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY


    1. Remove the instrument panel junction block assembly.

    2. Remove the main body ECU from the instrument panel junction block assembly.

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

      B0045ICE02
      Text in Illustration
      *a

      Component without harness connected

      (Instrument Panel Junction Block Assembly)

      		 - -
      Standard Resistance
      Tester Connection Condition Specified Condition
      3C-18 - MB-15 (HRLY) Always Below 1 Ω

    OK

    REPLACE MAIN BODY ECU Click here

    NG

    REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY