FixVault

Fail-Safe Chart

WARNING: This page is about a different car, the 2009 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
  1. HEADLIGHT BEAM LEVEL CONTROL ECU 
    1. If the headlight beam level control ECU detects the following malfunctions, it performs the fail safe control, blinks the master warning light in the combination meter, and displays "AUTO LEVELING WARNING" on the multi-display.
      FAIL-SAFE

      Item Condition to Transfer Condition to Return Warning Indication
      Over voltage*1 Detects input voltage of more than 18.5 V Detects less than 17.5 V Appears
      Low voltage*1 Detects input voltage of less than 9 V Detects more than 9.3 V Does not appear
      Vehicle height sensor malfunction*1 When either condition below is met:
      • Detects vehicle height sensor supply voltage of less than 4 V
      • Detects vehicle height signal malfunction (not within 0.5 V and 4.5 V)
      • Vehicle height sensor power source supply line is open, or short to GND
      • Vehicle height sensor GND line is open
      Detects normal voltage for 5 sec. Appears
      Microcomputer*1 Detects ECU malfunction Cancels reset of microcomputer Appears
      Leveling angle calculation value*2 Calculates values out of the actuator's operative range - Does not appear

      HINT:

      *1: Stops the actuator operation.

      *2: Replaces the minimum or maximum value of the actuator's operating range with the calculated value.

  2. BODY ECU (CONLIGHT CONTROL) 
    1. The body ECU keeps the headlight or taillight on if there is a malfunction in the light sensor systems while the headlight is on due to the conlight control (headlight dimmer switch is in AUTO position).
    2. The body ECU prohibits conlight control if there is a malfunction in the sensor systems when the headlight turns off.