LIGHTING SYSTEM(for LED Headlight) Headlight Dimmer Switch Circuit

DESCRIPTION

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

• Light control switch in off*1, DRL OFF*2, tail, head or Auto position

• Headlight dimmer switch in high, low or high flash (pass) position

• Fog light switch front*3 or rear*4 position




• *1: w/o DRL OFF Switch

• *2: w/ DRL OFF Switch

• *3: w/ Front Fog Light

• *4: w/ Rear Fog Light

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. READ VALUE USING GTS

   
   

   1. Using the GTS, read the Data List.

      Main Body

      Tester Display	Measurement Item	Control Range	Diagnostic Note
      Dimmer SW	Headlight dimmer switch High position signal / OFF or ON	OFF: Headlight dimmer switch not in High position ON: Headlight dimmer switch in High position	-
      Passing Light SW	Headlight dimmer switch Flash position signal / OFF or ON	OFF: Headlight dimmer switch not in Flash position ON: Headlight dimmer switch in Flash position	-
      Rear Fog Light SW	Fog light switch rear position signal / OFF or ON	OFF: Fog light switch off ON: Fog light switch in rear position	w/ Rear Fog Light
      Front Fog Light SW	Fog light switch front position signal / OFF or ON	OFF: Fog light switch off ON: Fog light switch in front position	w/ Front Fog Light
      Auto Light SW	Light control switch Auto position signal / OFF or ON	OFF: Light control switch not in Auto position ON: Light control switch in Auto position	-
      Head Light SW (Head)	Light control switch Head position signal / OFF or ON	OFF: Light control switch not in Head position ON: Light control switch in Head position	-
      Head Light SW (Tail)	Light control switch Tail position signal / OFF or ON	OFF: Light control switch not in Tail position ON: Light control switch in Tail position	-

      OK
      Normal condition listed above are displayed.

      Result
      Proceed to OK NG

   
   

   OK

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

   NG

2. INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY

   
   

   1. Remove the headlight dimmer switch assembly.

      Click here

   2. Inspect the headlight dimmer switch assembly.

      Click here

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY Click here

   OK

3. CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH ASSEMBLY - MAIN BODY ECU [MULTIPLEX NETWORK BODY ECU] AND BODY GROUND)

   
   

   1. Disconnect the G44 headlight dimmer switch assembly connector.

   2. Disconnect the G218 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance
      for LH Side Type Tester Connection Condition Specified Condition G218-10 (HF) - G44-17 (HF) Always Below 1 Ω G218-24 (HU) - G44-14 (HU) Always Below 1 Ω G218-22 (TAIL) - G44-18 (T) Always Below 1 Ω G218-12 (HEAD) - G44-19 (H) Always Below 1 Ω G218-8 (A) - G44-20 (A) Always Below 1 Ω G218-26 (FFOG) - G44-9 (BFG)*1 Always Below 1 Ω G218-23 (RFOG) - G44-7 (B)*2 Always Below 1 Ω G44-15 (EL) - Body ground Always Below 1 Ω G44-8 (LFG) - Body ground*1, *2 Always Below 1 Ω G218-10 (HF) or G44-17 (HF) - Body ground Always 10 kΩ or higher G218-24 (HU) or G44-14 (HU) - Body ground Always 10 kΩ or higher G218-22 (TAIL) or G44-18 (T) - Body ground Always 10 kΩ or higher G218-12 (HEAD) or G44-19 (H) - Body ground Always 10 kΩ or higher G218-8 (A) or G44-20 (A) - Body ground Always 10 kΩ or higher G218-26 (FFOG) or G44-9 (BFG) - Body ground*1 Always 10 kΩ or higher G218-23 (RFOG) or G44-7 (B) - Body ground*2 Always 10 kΩ or higher *1: w/ Front Fog Light *2: w/ Rear Fog Light
      for RH Side Type Tester Connection Condition Specified Condition G218-10 (HF) - G44-14 (HF) Always Below 1 Ω G218-24 (HU) - G44-17 (HU) Always Below 1 Ω G218-22 (TAIL) - G44-13 (T) Always Below 1 Ω G218-12 (HEAD) - G44-12 (H) Always Below 1 Ω G218-8 (A) - G44-11 (A) Always Below 1 Ω G218-26 (FFOG) - G44-2 (BFG)*1 Always Below 1 Ω G218-23 (RFOG) - G44-4 (B)*2 Always Below 1 Ω G44-16 (EL) - Body ground Always Below 1 Ω G44-3 (LFG) - Body ground*1, *2 Always Below 1 Ω G218-10 (HF) or G44-14 (HF) - Body ground Always 10 kΩ or higher G218-24 (HU) or G44-17 (HU) - Body ground Always 10 kΩ or higher G218-22 (TAIL) or G44-13 (T) - Body ground Always 10 kΩ or higher G218-12 (HEAD) or G44-12 (H) - Body ground Always 10 kΩ or higher G218-8 (A) or G44-11 (A) - Body ground Always 10 kΩ or higher G218-26 (FFOG) or G44-2 (BFG) - Body ground*1 Always 10 kΩ or higher G218-23 (RFOG) or G44-4 (B) - Body ground*2 Always 10 kΩ or higher *1: w/ Front Fog Light *2: w/ Rear Fog Light

      Result
      Proceed to OK NG

   
   

   OK

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

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR