LIGHTING SYSTEM Headlight Relay Circuit

DTC Code DTC Name
Headlight Relay Circuit

DESCRIPTION

The main body ECU receives headlight dimmer switch information signals and illuminates the low beam headlights.

WIRING DIAGRAM

E205653E01

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (HEADLIGHT RELAY)

    1. Using the intelligent tester, perform the Active Test.

      Click here

      Body Electrical > Main Body > Active Test

      Tester Display

      Measurement Item

      Control Range

      Diagnostic Note

      Headlight Relay

      Low beam headlight relay

      ON/OFF

      -

      OK

      Headlight relay operates (low beam headlights illuminate).

      Result

      Result

      OK

      NG
    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    Click hereClick here

    NG

  2. INSPECT HEADLIGHT RELAY (H-LP LO)

    1. E108359C03

      Remove the headlight relay from the engine room relay block.

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      3 - 5

      Battery voltage not applied between terminals 1 and 2

      10 kΩ or higher

      3 - 5

      Battery voltage applied between terminals 1 and 2

      Below 1 Ω

      Result

      Result

      OK

      NG
    NG

    REPLACE HEADLIGHT RELAY

    OK

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [H-LP LO] - BATTERY)

    1. E199762C03

      *a

      Front view of wire harness connector

      (to Headlight Relay)

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

      Standard Voltage

      Tester Connection

      Condition

      Specified Condition

      Headlight relay terminal 1 - Body ground

      Always

      11 to 14 V

      Headlight relay terminal 5 - Body ground

      Result

      Result

      OK

      NG
    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (HEADLIGHT RELAY [H-LP LO] - MAIN BODY ECU)

    1. Remove the main body ECU.

      Click hereClick here

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

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      Headlight relay terminal 2 - A-15 (HRLY)

      Always

      Below 1 Ω

      A-15 (HRLY) - Body ground

      Always

      10 kΩ or higher

      Result

      Result

      OK

      NG
    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

    Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR