Lighting System Fail-Safe Chart

  1. HID Headlight System (for HID Headlight)

  1. Automatic Headlight Beam Level Control System (for HID Headlight)

Lighting System -- Fail-Safe Chart



HID Headlight System (for HID Headlight)
The headlight light control ECU operates in fail-safe mode if an abnormal condition such as those listed below has been detected.

Item
Outline
Detection of abnormal input voltage (High input voltage)
If voltage that is input to the headlight light control ECU is approximately 20 V or more, the ECU stops illuminating the headlights, and resumes when the voltage drops to 16 V or less.
Detection of abnormal input voltage (Low input voltage)
If voltage that is input to the headlight light control ECU is 6 V or less, the ECU stops illuminating the low beam headlights, and resumes when the voltage is 10 V or more.
Detection of abnormal output
  1. Output open
  2. Short between output terminals
  3. Short between output terminal and body ground
If an abnormal condition occurs in the voltage that is output by the headlight light control ECU, the ECU stops illuminating the low beam headlights and will maintain this state until power is reinstated (by turning the headlight dimmer switch from off to head).
Detection of abnormal light voltage (Low light voltage)
Approximately 80 seconds after input voltage is supplied, if the light voltage is below approximately 31 V for approximately 0.5 seconds, the headlight light control ECU stops illuminating the low beam headlights and will maintain this state until power is reinstated (by turning the headlight dimmer switch from off to head).
Detection of abnormal light voltage (High light voltage)
If the light voltage is above approximately 69 V for approximately 0.5 seconds, the headlight light control ECU stops illuminating the low beam headlights and will maintain this state until power is reinstated (by turning the headlight dimmer switch from off to head).

Automatic Headlight Beam Level Control System (for HID Headlight)

  1. The headlight leveling ECU operates in fail-safe mode if an abnormal condition such as those listed below has been detected.

    Item
    		Abnormality Detection Condition
    		Return Condition
    		Warning Indicator
    Height control sensor power source voltage
    		Abnormal height control sensor power source voltage (4.6 V or less, or 6.25 V or more) is detected.
    		Voltage of 4.61 to 6.24 V is detected
    		Illuminated
    Height control sensor signal voltage
    		Abnormal height control sensor signal voltage (0.25 V or less, or 4.75 V or more) is detected.
    		Voltage of 0.26 to 4.74 V is detected
    High power source voltage
    		Abnormal high power source voltage (18.5 V or more) is detected.
    		Voltage of 17.5 V or less is detected
    		Not illuminated
    Low power source voltage
    		Abnormal low power source voltage (9.0 V or less) is detected.
    		Voltage of 9.3 V or more is detected
    		Not illuminated
    Abnormal height control sensor signal while initialization
    		Initialization is performed outside the valid range of the voltage for initialization.
    		Initialization is successfully completed within the valid range of the voltage for initialization.
    		Illuminated