LIGHTING SYSTEM > Headlight Dimmer Switch Circuit |
| 1.READ VALUE USING INTELLIGENT TESTER |
Connect the intelligent tester to the DLC3.
Turn the power switch on (IG).
Turn the intelligent tester on.
Enter the following menus: Body / Main Body / Data List.
Read the display on the intelligent tester.
| Tester Display | Measurement Item/Range | Normal Condition | Diagnostic Note |
| Dimmer Hi SW | Dimmer switch high position signal/ON or OFF | ON: Dimmer switch in high or high flash (pass) position OFF: Dimmer switch in low position | - |
| Passing Light SW | Dimmer switch high flash (pass) position signal/ON or OFF | ON: Dimmer switch in high flash (pass) position OFF: Dimmer switch not in high flash (pass) position | - |
| Front Fog Light SW | Front fog light switch signal/ON or OFF | ON: Front fog light switch on OFF: Front fog light switch off | - |
| Rear Fog Light SW | Rear fog light switch signal/ON or OFF | ON: Rear fog light switch on OFF: Rear fog light switch off | - |
| Light Auto 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 | - |
| Headlight SW | Light control switch head position signal/ON or OFF | ON: Light control switch in head position OFF: Light control switch not in head position | - |
| Taillight SW | 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 | - |
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| OK | ||
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| 2.INSPECT HEADLIGHT DIMMER SWITCH ASSEMBLY |
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for Light Control Switch LH Side Type
Remove the headlight dimmer switch assembly (Click here).
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Switch Condition | Specified Condition |
| 12 (EL) - 18 (T) | Light control switch off | 10 kΩ or higher |
| 18 (T) - 19 (A) | Light control switch off | 10 kΩ or higher |
| 19 (A) - 20 (H) | Light control switch off | 10 kΩ or higher |
| 12 (EL) - 18 (T) | Light control switch in tail position | Below 1 Ω |
| 12 (EL) - 18 (T) | Light control switch in head position | Below 1 Ω |
| 18 (T) - 20 (H) | Light control switch in head position | Below 1 Ω |
| 12 (EL) - 19 (A) | Light control switch in AUTO position | Below 1 Ω |
| Tester Connection | Switch Condition | Specified Condition |
| 11 (HU) - 12 (EL) | Dimmer switch in low position | 10 kΩ or higher |
| 11 (HU) - 12 (EL) | Dimmer switch in high position | Below 1 Ω |
| 12 (EL) - 17 (HF) | Dimmer switch in high flash position | Below 1 Ω |
| Tester Connection | Switch Condition | Specified Condition |
| 3 (LFG) - 4 (BFG) | Fog light switch off | 10 kΩ or higher |
| 3 (LFG) - 4 (BFG) | Fog light switch on | Below 1 Ω |
| Tester Connection | Switch Condition | Specified Condition |
| 3 (LFG) - 2 (B) | Rear fog light switch off | 10 kΩ or higher |
| 3 (LFG) - 2 (B) | Rear fog light switch on | Below 1 Ω |
| *1 | Component without harness connected: (Headlight Dimmer Switch Assembly) |
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for Light Control Switch RH Side Type
Remove the headlight dimmer switch assembly (Click here).
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Switch Condition | Specified Condition |
| 19 (EL) - 13 (T) | Light control switch off | 10 kΩ or higher |
| 13 (T) - 12 (A) | Light control switch off | 10 kΩ or higher |
| 12 (A) - 11 (H) | Light control switch off | 10 kΩ or higher |
| 19 (EL) - 13 (T) | Light control switch in tail position | Below 1 Ω |
| 19 (EL) - 13 (T) | Light control switch in head position | Below 1 Ω |
| 13 (T) - 11 (H) | Light control switch in head position | Below 1 Ω |
| 19 (EL) - 12 (A) | Light control switch in AUTO position | Below 1 Ω |
| Tester Connection | Switch Condition | Specified Condition |
| 20 (HU) - 19 (EL) | Dimmer switch in low position | 10 kΩ or higher |
| 20 (HU) - 19 (EL) | Dimmer switch in high position | Below 1 Ω |
| 19 (EL) - 14 (HF) | Dimmer switch in high flash position | Below 1 Ω |
| Tester Connection | Switch Condition | Specified Condition |
| 8 (LFG) - 7 (BFG) | Fog light switch off | 10 kΩ or higher |
| 8 (LFG) - 7 (BFG) | Fog light switch on | Below 1 Ω |
| Tester Connection | Switch Condition | Specified Condition |
| 8 (LFG) - 9 (B) | Rear fog light switch off | 10 kΩ or higher |
| 8 (LFG) - 9 (B) | Rear fog light switch on | Below 1 Ω |
| *1 | Component without harness connected: (Headlight Dimmer Switch Assembly) |
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| OK | |
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| 3.CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - HEADLIGHT DIMMER SWITCH ASSEMBLY) |
for Light Control Switch LH Side Type
Disconnect the L47 headlight dimmer switch assembly connector.
Disconnect the L7 main body ECU (multiplex network body ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| L47-2 (B) - L7-1 (RFOG) | Always | Below 1 Ω |
| L47-4 (BFG) - L7-27 (FFOG) | Always | Below 1 Ω |
| L47-11 (HU) - L7-5 (HU) | Always | Below 1 Ω |
| L47-17 (HF) - L7-8 (HF) | Always | Below 1 Ω |
| L47-18 (T) - L7-30 (TAIL) | Always | Below 1 Ω |
| L47-19 (A) - L7-28 (A) | Always | Below 1 Ω |
| L47-20 (H) - L7-29 (HEAD) | Always | Below 1 Ω |
| L47-4 (BFG) - Body ground | Always | 10 kΩ or higher |
| L47-11 (HU) - Body ground | Always | 10 kΩ or higher |
| L47-17 (HF) - Body ground | Always | 10 kΩ or higher |
| L47-18 (T) - Body ground | Always | 10 kΩ or higher |
| L47-19 (A) - Body ground | Always | 10 kΩ or higher |
| L47-20 (H) - Body ground | Always | 10 kΩ or higher |
| L47-12 (EL) - Body ground | Always | Below 1 Ω |
| L47-3 (LFG) - Body ground | Always | Below 1 Ω |
for Light Control Switch RH Side Type
Disconnect the L47 headlight dimmer switch assembly connector.
Disconnect the L7 main body ECU (multiplex network body ECU) connector.
Measure the resistance according to the value(s) in the table below.
| Tester Connection | Condition | Specified Condition |
| L47-9 (B) - L7-1 (RFOG) | Always | Below 1 Ω |
| L47-7 (BFG) - L7-27 (FFOG) | Always | Below 1 Ω |
| L47-20 (HU) - L7-5 (HU) | Always | Below 1 Ω |
| L47-14 (HF) - L7-8 (HF) | Always | Below 1 Ω |
| L47-13 (T) - L7-30 (TAIL) | Always | Below 1 Ω |
| L47-12 (A) - L7-28 (A) | Always | Below 1 Ω |
| L47-11 (H) - L7-29 (HEAD) | Always | Below 1 Ω |
| L47-7 (BFG) - Body ground | Always | 10 kΩ or higher |
| L47-20 (HU) - Body ground | Always | 10 kΩ or higher |
| L47-14 (HF) - Body ground | Always | 10 kΩ or higher |
| L47-13 (T) - Body ground | Always | 10 kΩ or higher |
| L47-12 (A) - Body ground | Always | 10 kΩ or higher |
| L47-11 (H) - Body ground | Always | 10 kΩ or higher |
| L47-19 (EL) - Body ground | Always | Below 1 Ω |
| L47-8 (LFG) - Body ground | Always | Below 1 Ω |
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| OK | ||
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