1. Connect the connector to the flasher unit.
2. Connect the negative battery cable.
3. Measure the voltage at the flasher 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 flasher unit.
Terminal Voltage List (Reference)
Mazda 6 Service Manual: Scheduled Maintenance (U.S.A., Canada, and Puerto Rico)
Follow Schedule 1 if the vehicle is operated mainly where none of the following
conditions (severe driving conditions) apply.
Repeated short-distance driving
Driving in dusty conditions
Driving with extended use of brakes
Driving in areas where salt or other corrosive materials are used
...
Mazda 6 Service Manual: Side Air Bags
The side air bags are mounted in the outboard sides of the front seatbacks.
When the air bag crash sensors detect a side impact of greater than moderate
force, the system inflates the side air bag only on the side in which the vehicle
was hit. The side air bag inflates quickly to reduce injury ...