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Home >> Toyota >> 2013 >> Prius Three >> Repair and Diagnosis (Single Page) >> External Pages >> Different variant/trim >> Section 15 (Lighting System (Diagnostics - Introduction) (Plug-In)) >> Lighting System >> Fail-Safe Chart >> Fail-Safe Chart
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Fail-Safe Chart

WARNING: This page is about a different variant/trim than selected.
  1. LED HEADLIGHT SYSTEM 

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

    Item Abnormality Detection Condition Return Condition Master Warning Light Multi-information Display
    Abnormal input voltage (High input voltage) Abnormal power source voltage (more than 17 V) is detected. Normal power source voltage (10 to 16 V) is detected. Flashes CHECK HEADLIGHT SYSTEM
    Abnormal input voltage (Low input voltage) Abnormal power source voltage (less than 10 V) is detected. Normal power source voltage (10 to 16 V) is detected. Flashes CHECK HEADLIGHT SYSTEM
    Abnormal output
    • Open in output side circuit
    • Short between output terminal and body ground
    Light control switch is turned off. Flashes CHECK HEADLIGHT SYSTEM
  2. AUTOMATIC LIGHT CONTROL SYSTEM 

    If the main body ECU (multiplex network body ECU) detects a malfunction in the automatic light control sensor, the main body ECU (multiplex network body ECU) performs fail-safe control to prohibit the automatic light control. If the low beam headlights and taillights are on, the lights will remain on until the light control switch is turned off.