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: Setting the System
When the MODE switch is pressed, the Mazda Radar Cruise Control (MRCC) main indication
(white) turns on and the vehicle speed and the distance between vehicles while in
headway control can be set.
NOTE
When the ignition is switched to ACC or OFF while the Mazda Radar Cruise
Control (MR ...
Mazda 6 Service Manual: Coming Home Light
The coming home light turns on the headlights (low beams) when the lever is operated.
To turn on the lights
When the lever is pulled with the ignition switched to ACC or OFF, the low beam
headlights turn on.
The headlights turn off after a certain period of time has elapsed after the
doors ar ...