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 bumper removal/installation
1. Disconnect the negative battery cable.
2. Remove the rear combination light.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Bumper Removal Note
Pull the rear bumper ends (wheel arch) outward to disengage with the bumper
slider.
Cautio ...
Mazda 6 Service Manual: Roof molding installation
1. Attach the roof molding to the T stud at the A section.
2. Press in the roof molding along the direction (1) shown in the figure and
attach it to the clip A at the B section.
3. Hook the roof molding to the clip B at the C section, press it in, and
attach the roof molding to the clip B.
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