LIGHTING SYSTEM Headlight Dimmer Switch Circuit

DESCRIPTION

WIRING DIAGRAM

PROCEDURE

1. READ VALUE USING GTS

   1. Connect the GTS to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / Main Body / Data List.

   5. Read the display on the GTS.

      Body Electrical > Main Body > Data List

      Tester Display	Measurement Item	Range	Normal Condition	Diagnostic Note
      Dimmer SW	Dimmer switch high position signal	ON or OFF	ON: Dimmer switch in high or high flash position OFF: Dimmer switch in low position	-
      Passing Light SW	Dimmer switch high flash position (pass) signal	ON or OFF	ON: Dimmer switch in high flash position OFF: Dimmer switch not in high flash position	-
      Rear Fog Light SW	Fog light switch rear position signal	ON or OFF	ON: Fog light switch in rear position OFF: Fog light switch off	w/ Rear Fog Light
      Front Fog Light SW	Fog light switch front position signal	ON or OFF	ON: Fog light switch in front position OFF: Fog light switch off	w/ Front Fog Light
      Auto Light SW	Light control switch AUTO position signal	ON or OFF	ON: Light control switch in AUTO position OFF: Light control switch not in AUTO position	w/ Automatic Light Control
      Head Light SW (Head)	Light control switch head position 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 position signal	ON or OFF	ON: Light control switch in tail or head position OFF: Light control switch in neither tail nor head position	-

      Body Electrical > Main Body > Data List

      Tester Display
      Dimmer SW
      Passing Light SW
      Rear Fog Light SW
      Front Fog Light SW
      Auto Light SW
      Head Light SW (Head)
      Head Light SW (Tail)

      OK

      Normal conditions listed above are displayed.

   Result

   Proceed to
   OK
   NG

   OK

   PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

   Click hereClick hereClick hereClick here

   NG

2. INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY

   Tip:

   Inspect the items that did not change as a result of monitoring the Data List.

   1. Remove the headlight dimmer switch assembly.

      Click here

   2. 

      *a	Component without harness connected (Headlight Dimmer Switch Assembly)

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

      Standard Resistance

      Table 1. Light Control Switch

      Tester Connection	Condition	Specified Condition
      18 (T) - 15 (EL)	Light control switch off	10 kΩ or higher
      19 (H) - 15 (EL)	Light control switch off	10 kΩ or higher
      20 (A)*1 - 15 (EL)	Light control switch off	10 kΩ or higher
      18 (T) - 15 (EL)	Light control switch in tail position	Below 1 Ω
      18 (T) - 15 (EL)	Light control switch in head position	Below 1 Ω
      19 (H) - 15 (EL)	Light control switch in head position	Below 1 Ω
      20 (A)*1 - 15 (EL)	Light control switch in AUTO position	Below 1 Ω

      Table 2. Dimmer Switch

      Tester Connection	Condition	Specified Condition
      14 (HU) - 15 (EL)	Dimmer switch in low position	10 kΩ or higher
      14 (HU) - 15 (EL)	Dimmer switch in high position	Below 1 Ω
      14 (HU) - 15 (EL)	Dimmer switch in high flash position	Below 1 Ω
      17 (HF) - 15 (EL)	Dimmer switch in high flash position	Below 1 Ω

      Table 3. Fog Light Switch

      Tester Connection	Condition	Specified Condition
      9 (BFG)*2 - 8 (LFG)	Fog light switch off	10 kΩ or higher
      9 (BFG)*2 - 8 (LFG)	Fog light switch in front position	Below 1 Ω
      7 (B)*3 - 8 (LFG)	Fog light switch off	10 kΩ or higher
      7 (B)*3 - 8 (LFG)	Fog light switch in rear position	Below 1 Ω

      • *1: w/ Automatic Light Control

      • *2: w/ Front Fog Light

      • *3: w/ Rear Fog Light

   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))

   1. Disconnect the E22 main body ECU (multiplex network body ECU) connector.

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

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      E8-9 (BFG)*2 - E22-27 (FFOG)*2	Always	Below 1 Ω
      E8-7 (B)*3 - E22-1 (RFOG)	Always	Below 1 Ω
      E8-14 (HU) - E22-5 (HU)	Always	Below 1 Ω
      E8-17 (HF) - E22-8 (HF)	Always	Below 1 Ω
      E8-18 (T) - E22-30 (TAIL)	Always	Below 1 Ω
      E8-19 (H) - E22-29 (HEAD)	Always	Below 1 Ω
      E8-20 (A)*1 - E22-28 (A)*1	Always	Below 1 Ω
      E8-9 (BFG)*2 - Body ground	Always	10 kΩ or higher
      E8-7 (B)*3 - Body ground	Always	10 kΩ or higher
      E8-14 (HU) - Body ground	Always	10 kΩ or higher
      E8-17 (HF) - Body ground	Always	10 kΩ or higher
      E8-18 (T) - Body ground	Always	10 kΩ or higher
      E8-19 (H) - Body ground	Always	10 kΩ or higher
      E8-20 (A)*1 - Body ground	Always	10 kΩ or higher
      E8-15 (EL) - Body ground	Always	Below 1 Ω
      E8-8 (LFG) - Body ground	Always	Below 1 Ω

      • *1: w/ Automatic Light Control

      • *2: w/ Front Fog Light

      • *3: w/ Rear Fog Light

   Result

   Proceed to
   OK
   NG

   OK

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

   for LHD:Click here

   for RHD:Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR