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: Rear brake (disc) inspection
Brake Judder Repair Hint
1. (See FRONT BRAKE (DISC) INSPECTION.)
Disc Plate Thickness Inspection
Caution
Excessive runout may result if the disc plate is removed from the
vehicle then machined. Machine the disc plate while installed on the
vehicle.
1. Measure the thickness of the dis ...
Mazda 6 Service Manual: Excessive Speed Warning
If the vehicle speed exceeds the speed limit sign displayed on the active driving
display, the warning sound is activated and the area around the speed limit sign
displayed on the active driving display flashes 3 times in amber, and if the vehicle
speed continues to exceed the displayed speed ...