Lighting System Headlight Dimmer Switch Circuit


DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

READ VALUE USING INTELLIGENT TESTER (HEADLIGHT DIMMER SWITCH)

INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY

CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH ASSEMBLY - MAIN BODY ECU AND BODY GROUND)

LIGHTING SYSTEM - Headlight Dimmer Switch Circuit


DESCRIPTION

The main body ECU receives the following signals:
  1. Headlight dimmer switch tail, head, AUTO*1, high or high flash signal
  2. Front fog light switch signal*2
  3. Rear fog light switch signal*3
  1. *1: w/ Automatic Light Control System
  2. *2: w/ Front Fog Light
  3. *3: w/ Rear Fog Light

WIRING DIAGRAM


Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Lighting (Ext).Lighting System.Lighting System  Headlight Dimmer Switch Circuit


INSPECTION PROCEDURE

1.READ VALUE USING INTELLIGENT TESTER (HEADLIGHT DIMMER SWITCH)
  1. Using the intelligent tester, read the Data List (LandCruiser RM000000PKV0J6X.html).

    Main Body
    Tester Display
    Measurement Item/Range
    Normal Condition
    Diagnostic Note
    Dimmer SW
    Headlight dimmer switch high position signal / ON or OFF
    ON: Headlight dimmer switch in high or high flash position
    OFF: Headlight dimmer switch in low position
    -
    Passing Light SW
    Headlight dimmer switch high flash position (pass) signal / ON or OFF
    ON: Headlight dimmer switch in high flash position
    OFF: Headlight dimmer switch not in high flash position
    -
    Rear Fog Light SW*3
    Rear fog light switch signal / ON or OFF
    ON: Rear fog light switch on
    OFF: Rear fog light switch off
    -
    Front Fog Light SW*2
    Front fog light switch signal / ON or OFF
    ON: Front fog light switch on
    OFF: Front fog light switch off
    -
    Auto Light SW*1
    Headlight dimmer switch AUTO position signal / ON or OFF
    ON: Headlight dimmer switch in AUTO position
    OFF: Headlight dimmer switch not in AUTO position
    -
    Head Light SW (Head)
    Headlight dimmer switch head position signal / ON or OFF
    ON: Headlight dimmer switch in head position
    OFF: Headlight dimmer switch not in head position
    -
    Head Light SW (Tail)
    Headlight dimmer switch tail position signal / ON or OFF
    ON: Headlight dimmer switch in tail or head position
    OFF: Headlight dimmer switch in neither tail nor head position
    -
    1. *1: w/ Automatic Light Control System
    2. *2: w/ Front Fog Light
    3. *3: w/ Rear Fog Light
    OK:
    The display is as specified in the normal condition column.


NG
Go to step 2
OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (LandCruiser RM000002CE20QHX.html)

2.INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY


  1. Remove the headlight dimmer switch (LandCruiser RM000003QJL01EX.html).


    Land Cruiser, Land Cruiser Prado. Grj150 Trj150,155 Kdj150,155 Lj150, Gdj150,155.Lighting (Ext).Lighting System.Lighting System  Headlight Dimmer Switch Circuit


    Text in Illustration
    *A
    for Headlight Dimmer Switch LH Side Type
    *B
    for Headlight Dimmer Switch RH Side Type
  1. Measure the resistance according to the value(s) in the table below.

    Standard Resistance:
    for Headlight Dimmer Switch LH Side Type:
    Tester Connection
    Switch Condition
    Specified Condition
    2 (B) - 3 (LFG)*3
    Rear fog light switch on
    Below 1 Ω
    4 (BFG) - 3 (LFG)*2
    Fog light switch on
    Below 1 Ω
    11 (HU) - 12 (EL)
    Headlight dimmer switch high
    Below 1 Ω
    Headlight dimmer switch high flash
    17 (HF) - 12 (EL)
    Headlight dimmer switch high flash
    Below 1 Ω
    18 (T) - 12 (EL)
    Headlight dimmer switch tail
    Below 1 Ω
    Headlight dimmer switch head
    19 (A) - 12 (EL)*1
    Headlight dimmer switch AUTO
    Below 1 Ω
    20 (H) - 12 (EL)
    Headlight dimmer switch head
    Below 1 Ω
    2 (B) - 3 (LFG)*3
    Rear fog light switch off
    10 kΩ or higher
    4 (BFG) - 3 (LFG)*2
    Fog light switch off
    10 kΩ or higher
    18 (T) - 12 (EL)
    Headlight dimmer switch off
    10 kΩ or higher
    19 (A) - 12 (EL)*1
    20 (H) - 12 (EL)
    for Headlight Dimmer Switch RH Side Type:
    Tester Connection
    Switch Condition
    Specified Condition
    9 (B) - 8 (LFG)*3
    Rear fog light switch on
    Below 1 Ω
    7 (BFG) - 8 (LFG)*2
    Fog light switch on
    Below 1 Ω
    20 (HU) - 19 (EL)
    Headlight dimmer switch high
    Below 1 Ω
    Headlight dimmer switch high flash
    14 (HF) - 19 (EL)
    Headlight dimmer switch high flash
    Below 1 Ω
    13 (T) - 19 (EL)
    Headlight dimmer switch tail
    Below 1 Ω
    Headlight dimmer switch head
    12 (A) - 19 (EL)*1
    Headlight dimmer switch AUTO
    Below 1 Ω
    11 (H) - 19 (EL)
    Headlight dimmer switch head
    Below 1 Ω
    9 (B) - 8 (LFG)*3
    Rear fog light switch off
    10 kΩ or higher
    7 (BFG) - 8 (LFG)*2
    Fog light switch off
    10 kΩ or higher
    13 (T) - 19 (EL)
    Headlight dimmer switch off
    10 kΩ or higher
    12 (A) - 19 (EL)*1
    11 (H) - 19 (EL)
  1. *1: w/ Automatic Light Control System
  2. *2: w/ Front Fog Light
  3. *3: w/ Rear Fog Light


NG
REPLACE HEADLIGHT DIMMER SWITCH ASSEMBLY (LandCruiser RM000003QJL01EX.html)
OK


3.CHECK HARNESS AND CONNECTOR (HEADLIGHT DIMMER SWITCH ASSEMBLY - MAIN BODY ECU AND BODY GROUND)
  1. Disconnect the G44 headlight dimmer switch connector.

  1. Disconnect the G63 and G64 main body ECU connectors.

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

    Standard Resistance:
    for Headlight Dimmer Switch LH Side Type:
    Tester Connection
    Condition
    Specified Condition
    G44-2 (B) - G63-23 (RFOG)*3
    Always
    Below 1 Ω
    G44-4 (BFG) - G64-27 (FFOG)*2
    Always
    Below 1 Ω
    G44-11 (HU) - G64-5 (HU)
    Always
    Below 1 Ω
    G44-17 (HF) - G64-8 (HF)
    Always
    Below 1 Ω
    G44-18 (T) - G64-30 (TAIL)
    Always
    Below 1 Ω
    G44-19 (A) - G64-28 (A)*1
    Always
    Below 1 Ω
    G44-20 (H) - G64-29 (HEAD)
    Always
    Below 1 Ω
    G44-3 (LFG) - Body ground*2, *3
    Always
    Below 1 Ω
    G44-12 (E) - Body ground
    Always
    Below 1 Ω
    G44-2 (B) - Body ground*3
    Always
    10 kΩ or higher
    G44-4 (BFG) - Body ground*2
    Always
    10 kΩ or higher
    G44-11 (HU) - Body ground
    Always
    10 kΩ or higher
    G44-17 (HF) - Body ground
    Always
    10 kΩ or higher
    G44-18 (T) - Body ground
    Always
    10 kΩ or higher
    G44-19 (A) - Body ground*1
    Always
    10 kΩ or higher
    G44-20 (H) - Body ground
    Always
    10 kΩ or higher
    for Headlight Dimmer Switch RH Side Type:
    Tester Connection
    Condition
    Specified Condition
    G44-9 (B) - G63-23 (RFOG)*3
    Always
    Below 1 Ω
    G44-7 (BFG) - G64-27 (FFOG)*2
    Always
    Below 1 Ω
    G44-20 (HU) - G64-5 (HU)
    Always
    Below 1 Ω
    G44-14 (HF) - G64-8 (HF)
    Always
    Below 1 Ω
    G44-13 (T) - G64-30 (TAIL)
    Always
    Below 1 Ω
    G44-12 (A) - G64-28 (A)*1
    Always
    Below 1 Ω
    G44-11 (H) - G64-29 (HEAD)
    Always
    Below 1 Ω
    G44-8 (LFG) - Body ground*2, *3
    Always
    Below 1 Ω
    G44-19 (EL) - Body ground
    Always
    Below 1 Ω
    G44-9 (B) - Body ground*3
    Always
    10 kΩ or higher
    G44-7 (BFG) - Body ground*2
    Always
    10 kΩ or higher
    G44-20 (HU) - Body ground
    Always
    10 kΩ or higher
    G44-14 (HF) - Body ground
    Always
    10 kΩ or higher
    G44-13 (T) - Body ground
    Always
    10 kΩ or higher
    G44-12 (A) - Body ground*1
    Always
    10 kΩ or higher
    G44-11 (H) - Body ground
    Always
    10 kΩ or higher
  1. *1: w/ Automatic Light Control System
  2. *2: w/ Front Fog Light
  3. *3: w/ Rear Fog Light


NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) (LandCruiser RM000003WBO05FX.html)