1. Connect the connector to the running light unit.
2. Connect the negative battery cable.
3. Measure the voltage at the running light unit using voltmeter.
4. If the value are not as specified in the Terminal Voltage List (Reference), inspect the parts under Action and related wiring harnesses.
5. If the system does not work properly even though the parts or related wiring harnesses do not have any malfunction, replace the running light unit.
Terminal Voltage List (Reference)



Running light unit removal/installationMazda 6 Service Manual: How to use USB mode
This unit does not support a USB 3.0 device. In addition, other devices may not
be supported depending on the model or OS version.
USB devices formatted to FAT32 are supported (USB devices formatted to other
formats such as NTFS are not supported).
Playback
1. Select the icon on the home
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Mazda 6 Service Manual: To Operate the System
The High Beam Control System (HBC) operates to switch the headlights automatically
between high and low beams after the ignition is switched ON and the headlight switch
is in the AUTO and high beam position.
The High Beam Control System (HBC) determines that it is dark based on the brightness
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