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: A-pillar trim removal
1. Turn the seaming welt over.
2. Disengage clips A using a fastener remover.
3. Pull the A-pillar trim, then disengage clip B (1).
4. Pull the A-pillar trim upward, then disengage clip B from the A-pillar
trim (2).
5. Pull clip B out, then rotate 45°.
6. Remove clip B from the grommet b ...
Mazda 6 Service Manual: Precaution
Vehicles with ABS/TCS
1. The ABS warning light, BRAKE system warning light, TCS indicator light
and/or TCS OFF light illuminate even when the system is normal.
*1 : In cases where the light may illuminate, only when ABS/TCS HU/CM detects
that speed sensor of rear wheel is malfunctioning.
*2 ...