AUTO LEVELING CONTROL UNIT FUNCTION


BHE091801052T10

• In order to prevent blinding from oncoming traffic and to improve visibility, the auto leveling control unit automatically controls the optical axis direction for optimal illumination based on signals input from the DSC HU/CM and the auto leveling sensor.

• If an error signal from the auto leveling sensor or excessive power supply voltage is detected, the auto leveling indicator light is illuminated to warn the driver of a malfunction.

Fail-safe Function

• The fail-safe function operates when the auto leveling control unit detects a malfunction. It also warns the driver of a malfunction by illuminating the indicator light as shown in the fail-safe function table.

• The fail-safe function controls each part as shown on the fail-safe function table.

Note
• When the ignition switch is turned to the ON position, the auto leveling control module checks the auto leveling indicator light bulb and illuminates the bulb for 3 s to indicate that there is no malfunction.

1
Auto leveling indicator light
2
Instrument cluster

Fail-safe Function Table

Item

Test condition

Fail-safe function

Indicator light

Cancel condition

Auto leveling sensor
Signal malfunction
Signal voltage of 4.0 V or less detected 10 times or more within 5 s
Returns headlights to the initial set position if they are pointing higher than initial set position. Fixes them in position where the malfunction is determined if pointing lower than the initial set position.
Illuminated*1
Continuous normal operation for 5 s or ignition switch is turned off and then to the ON position again.
Power supply malfunction
Power supply voltage of 0.25 V or less, or 4.75 V or more detected 10 times or more within 5 s
Auto leveling control unit
Malfunction detected by auto leveling control unit
Resets microcomputer in auto leveling control unit.
Illuminated
Ignition switch is turned off and then to the ON position again.
DSC HU/CM
Vehicle speed of 180 km/h or more detected
Fixes the optical axis angle at the position where vehicle speed of 180 km/h or more detected
Not illuminated
Vehicle speed of less than 180 km/h detected
Battery voltage
Excessive power supply voltage
Battery voltage of 18.5 V or more detected
Fixes headlights in position where excessive power supply voltage was determined.
Illuminated
When battery voltage of 17.5 V or less is detected, or ignition switch is turned off and then to the ON position again.

*1  :
Indicator light illuminates only when either malfunction condition is detected two consecutive times.