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Fail-Safe Chart

WARNING: This page is about a different car, the 2011 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
  1. LIGHT CONTROL COMPUTER (HID) 
    Trouble Area Condition
    High voltage circuit open Lighting of the headlight stops, the condition is maintained until power is turned on again (headlight dimmer switch OFF → ON).
    Short between high voltage circuits Lighting of the headlight stops within 1 second and the condition is maintained until power is turned on again (headlight dimmer switch OFF → ON).
    Leakage between high voltage terminal and body ground Lighting of the headlight stops, the condition is maintained until power is turned on again (headlight dimmer switch OFF → ON).
    Low light voltage Lighting of the headlight stops, the condition is maintained until power is turned on again (headlight dimmer switch OFF → ON).
    High light voltage Lighting of the headlight stops, the condition is maintained until power is turned on again (headlight dimmer switch OFF → ON).
    Bulb flashing
    • The condition is maintained more than 60 seconds.
    • Lighting of the headlight stops, the condition is maintained until power is turned on again (headlight dimmer switch OFF → ON).
    Battery voltage high As soon as the voltage comes within the range of operation voltage (9 to 16 V), the headlight comes on again.
    Battery voltage low Even when voltage changes from 9.5 V to 7.5 V, lighting condition is maintained. Lighting condition changes when voltage is too low (below 6 V).
    As soon as the voltage comes back within the range of operation voltage (more than 9 V), the headlights come on again.
  2. HEADLIGHT BEAM LEVEL CONTROL ECU 

    HINT: 

    • The headlight beam level control ECU performs fail-safe when detecting the following troubles. The headlight beam level control warning indicator light on the combination meter comes on at the same time.
    • If the headlight beam level control warning indicator light comes on, inspect and repair in accordance with the "PROBLEM SYMPTOMS TABLE". Refer to PROBLEM SYMPTOMS TABLE .
    Trouble area Headlight beam level control motor Warning indicator light Recovery condition
    Height control sensor power source
    • Stops operation after returning to initial position (Fail occurs at higher than initial position)
    • Stops at current position (Fail occurs at lower than initial position)
    Comes on Ignition switch off
    Height control sensor signal
    • Stops operation after returning to initial position (Fail occurs at higher than initial position)
    • Stops at current position (Fail occurs at lower than initial position)
    Comes on Return to normal signals
    Headlight beam level control motor
    • Stops operation after returning to initial position (Fail occurs at higher than initial position) (*1)
    • Stops at current position (Fail occurs at lower than initial position) (*1)
    Comes on Ignition switch off
    Alternator signal Control continues Comes on Ignition switch off

    HINT: 

    *1: The inoperative side stops at current position.