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: Discharge headlight service warnings
Discharge headlight bulb service warnings
To prevent electrical shock when replacing the discharge headlight bulb,
dry hands thoroughly, and carry out work in an area out of rain.
When the light switch is on, approx. 25,000 V of high voltage passes
through the discharge headlight bulb so ...
Mazda 6 Service Manual: Drive Selection (Some models)
Drive selection is a system to switch the vehicle's drive mode. When the sport
mode is selected, vehicle's response against accelerator operation is enhanced.
This provides additional quick acceleration which may be needed to safely make maneuvers
such as lane changes, merging onto freeways, o ...