LIGHTING SYSTEM Headlight Leveling ECU Power Source Circuit

DTC Code DTC Name
Headlight Leveling ECU Power Source Circuit

DESCRIPTION

This circuit detects the state of the ignition switch, and sends it to the headlight leveling ECU.

WIRING DIAGRAM

E186282E01

CAUTION / NOTICE / HINT

Note:

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

PROCEDURE

  1. READ VALUE USING INTELLIGENT TESTER

    1. Using the intelligent tester, read the Data List (Click here).

      Table 1. HL Auto Leveling (Headlight Leveling ECU)

      Tester Display

      Measurement Item/Range

      Normal Condition

      Diagnostic Note

      +B

      Ignition power supply voltage value / 0 to 19.75 V

      11 to 14 V

      -

      OK

      The display is as specified in the normal condition column.

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

  2. CHECK HARNESS AND CONNECTOR (BATTERY - HEADLIGHT LEVELING ECU ASSEMBLY)

    U123643E03
    1. Disconnect the A49 headlight leveling ECU connector.

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

      Standard Voltage

      Tester Connection

      Switch Condition

      Specified Condition

      A49-1 (IG) - Body ground

      Ignition switch ON

      11 to 14 V

      A49-1 (IG) - Body ground

      Ignition switch off

      Below 1 V

      Table 2. Text in Illustration

      *1

      Front view of wire harness connector

      (to Headlight Leveling ECU Assembly)

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT LEVELING ECU ASSEMBLY - BODY GROUND)

    U123644E02
    1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection

      Condition

      Specified Condition

      A49-9 (E1) - Body ground

      Always

      Below 1 Ω

      Table 3. Text in Illustration

      *1

      Front view of wire harness connector

      (to Headlight Leveling ECU Assembly)

      Table 4. Result

      Result

      Proceed to

      NG

      A

      OK (for LHD)

      B

      OK (for RHD)

      C

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    REPLACE HEADLIGHT LEVELING ECU ASSEMBLY

    REPLACE HEADLIGHT LEVELING ECU ASSEMBLY