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: Dsc hu/cm removal/installation
Caution
When replacing the DSC HU/CM, configuration procedure must be done
before removing the DSC HU/CM. If configuration is not completed before
removing the DSC HU/CM, DTC B2477 will be detected.
Do not drop the DSC HU/CM. Replace it if it is subjected to an
impact.
1. Configura ...
Mazda 6 Service Manual: Winter Driving
Carry emergency gear, including tire chains, window scraper, flares, a small
shovel, jumper cables, and a small bag of sand or salt.
Ask an Authorized Mazda Dealer to check the following:
Have the proper ratio of antifreeze in the radiator.
Inspect the battery and its cables. Cold reduces b ...