LIGHTING SYSTEM Headlight Dimmer Switch Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) receives the following signals:


The combination meter assembly receives the following signals:


WIRING DIAGRAM


  1. w/ Rear Fog Light

    A005I2ZE03

  2. w/o Rear Fog Light

    A005GY4E02

CAUTION / NOTICE / HINT

Note

Initialization is necessary when the main body ECU (multiplex network body ECU) is replaced Click here.*


  • *: w/ Automatic Light Control System

PROCEDURE


  1. READ VALUE USING INTELLIGENT TESTER (HEADLIGHT DIMMER SWITCH)


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

      Main Body
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Dimmer SW Dimmer switch high position signal / ON or OFF

      ON: Dimmer switch in high position

      OFF: Dimmer switch not in high position

      		 -
      Passing Light SW Dimmer switch high flash signal / ON or OFF

      ON: Dimmer switch in high flash position

      OFF: Dimmer switch not in high flash position

      		 -
      Rear Fog Light SW Rear fog light switch signal / ON or OFF

      ON: Rear fog light switch on

      OFF: Rear fog light switch off

      		 -
      Front Fog Light SW Front fog light switch signal / ON or OFF

      ON: Front fog light switch on

      OFF: Front fog light switch off

      		 -
      Auto Light SW Light control switch AUTO signal / ON or OFF

      ON: Light control switch in AUTO position

      OFF: Light control switch not in AUTO position

      		 -
      Head Light SW (Head) Light control switch HEAD signal / ON or OFF

      ON: Light control switch in HEAD position

      OFF: Light control switch not in HEAD position

      		 -
      Head Light SW (Tail) Light control switch TAIL signal / ON or OFF

      ON: Light control switch in TAIL or HEAD position

      OFF: Light control switch not in TAIL or HEAD position

      		 -
      Combination Meter
      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Turn Signal Switch (Right) Turn signal switch signal (turn right) / ON or OFF

      ON: Turn signal switch right on (turn right)

      OFF: Turn signal switch neutral

      		 -
      Turn Signal Switch (Left) Turn signal switch signal (turn left) / ON or OFF

      ON: Turn signal switch left on (turn left)

      OFF: Turn signal switch neutral

      		 -
      OK
      The display is as specified in the normal condition column.
      Result
      Result Proceed to
      NG (Light control switch, dimmer switch or fog light switch) A
      NG (Turn signal switch) B
      OK C

    B

    INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

    C

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

    A

  2. INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY


    1. Remove the headlight dimmer switch assembly Click here.

    2. Inspect the headlight dimmer switch assembly Click here.


    NG

    REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH - MAIN BODY ECU, BODY GROUND)


    1. Disconnect the F76 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance (Check for Open)
      w/ Rear Fog Light
      Tester Connection Condition Specified Condition
      F9-2 (B) - F76-1 (RFOG) Always Below 1 Ω
      F9-4 (BFG) - F76-27 (FFOG)*1 Always Below 1 Ω
      F9-11 (HU) - F76-5 (HU) Always Below 1 Ω
      F9-17 (HF) - F76-8 (HF) Always Below 1 Ω
      F9-18 (T) - F76-30 (TAIL) Always Below 1 Ω
      F9-19 (A) - F76-28 (A)*2 Always Below 1 Ω
      F9-20 (H) - F76-29 (HEAD) Always Below 1 Ω
      F9-3 (LFG) - Body ground Always Below 1 Ω
      F9-12 (EL) - Body ground Always Below 1 Ω
      w/o Rear Fog Light
      Tester Connection Condition Specified Condition
      F9-20 (HU) - F76-5 (HU)*2 Always Below 1 Ω
      F9-14 (HF) - F76-8 (HF)*2 Always Below 1 Ω
      F9-13 (T) - F76-30 (TAIL)*2 Always Below 1 Ω
      F9-12 (A) - F76-28 (A)*2 Always Below 1 Ω
      F9-11 (H) - F76-29 (HEAD)*2 Always Below 1 Ω
      F9-19 (EL) - Body ground*2 Always Below 1 Ω

      • *1: w/ Front Fog Light

      • *2: w/ Automatic Light Control System

      Standard Resistance (Check for Short)
      w/ Rear Fog Light
      Tester Connection Condition Specified Condition
      F9-2 (B) - Body ground Always 10 kΩ or higher
      F9-4 (BFG) - Body ground*1 Always 10 kΩ or higher
      F9-11 (HU) - Body ground Always 10 kΩ or higher
      F9-17 (HF) - Body ground Always 10 kΩ or higher
      F9-18 (T) - Body ground Always 10 kΩ or higher
      F9-19 (A) - Body ground*2 Always 10 kΩ or higher
      F9-20 (H) - Body ground Always 10 kΩ or higher
      w/o Rear Fog Light
      Tester Connection Condition Specified Condition
      F9-20 (HU) - Body ground*2 Always 10 kΩ or higher
      F9-14 (HF) - Body ground*2 Always 10 kΩ or higher
      F9-13 (T) - Body ground*2 Always 10 kΩ or higher
      F9-12 (A) - Body ground*2 Always 10 kΩ or higher
      F9-11 (H) - Body ground*2 Always 10 kΩ or higher

      • *1: w/ Front Fog Light

      • *2: w/ Automatic Light Control System


    OK

    REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

  4. INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY


    1. Remove the headlight dimmer switch assembly Click here.

    2. Inspect the headlight dimmer switch assembly Click here.


    NG

    REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

    OK

  5. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH - COMBINATION METER, BODY GROUND)


    1. Disconnect the F3 combination meter assembly connector.

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

      Standard Resistance (Check for Open)
      w/ Rear Fog Light
      Tester Connection Condition Specified Condition
      F9-13 (TR) - F3-9 (ER) Always Below 1 Ω
      F9-15 (TL) - F3-10 (EL) Always Below 1 Ω
      F9-12 (EL) - Body ground Always Below 1 Ω
      w/o Rear Fog Light and w/ Automatic Light Control System
      Tester Connection Condition Specified Condition
      F9-16 (TR) - F3-9 (ER) Always Below 1 Ω
      F9-18 (TL) - F3-10 (EL) Always Below 1 Ω
      F9-19 (EL) - Body ground Always Below 1 Ω
      w/o Rear Fog Light and w/o Automatic Light Control System
      Tester Connection Condition Specified Condition
      F10-13 (TR) - F3-9 (ER) Always Below 1 Ω
      F10-12 (TL) - F3-10 (EL) Always Below 1 Ω
      F10-11 (EL) - Body ground Always Below 1 Ω
      Standard Resistance (Check for Short)
      w/ Rear Fog Light
      Tester Connection Condition Specified Condition
      F9-13 (TR) - Body ground Always 10 kΩ or higher
      F9-15 (TL) - Body ground Always 10 kΩ or higher
      w/o Rear Fog Light and w/ Automatic Light Control System
      Tester Connection Condition Specified Condition
      F9-16 (TR) - Body ground Always 10 kΩ or higher
      F9-18 (TL) - Body ground Always 10 kΩ or higher
      w/o Rear Fog Light and w/o Automatic Light Control System
      Tester Connection Condition Specified Condition
      F10-13 (TR) - Body ground Always 10 kΩ or higher
      F10-12 (TL) - Body ground Always 10 kΩ or higher

    OK

    REPLACE COMBINATION METER ASSEMBLY Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR