1. Verify that there is no continuity between antenna feeder terminals A and B using an ohmmeter.

2. Inspect for continuity between the antenna feeder terminals using an ohmmeter.

Front antenna feeder inspectionMazda 6 Service Manual: Jacking positions ,vehicle lift (2 supports),safety stands (rigid rack)
positions
Jacking Positions
Warning
Improperly jacking a vehicle is dangerous. The vehicle can slip
off the jack and cause serious injury. Use only the correct front and rear
jacking points and block the wheels.
Use safety stands to support the vehicle after it has been lifted.
Fro ...
Mazda 6 Service Manual: Rear door speaker removal/installation
1. Disconnect the negative battery cable.
2. Remove the rear door trim.
3. Remove in the order indicated in the table.
4. Install in the reverse order of removal.
Rear Door Speaker Installation Note
Attach the speaker with the wiring harness placed in the groove of the door
unit panel.
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