1. Inspect for resistance between the rear door speaker terminals using an ohmmeter.


2. To verify that the rear door speaker outputs sound, apply voltage to the rear door speaker and release using a 1.5-V battery.
Rear door speaker removal/installation
Tweeter removal/installationMazda 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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Mazda 6 Service Manual: Key reminder switch inspection
1. Disconnect the negative battery cable.
2. Remove the column cover. (See COLUMN COVER REMOVAL/INSTALLATION)
3. Disconnect the key reminder switch connector.
4. Inspect for continuity between the key reminder switch terminals using an
ohmmeter.
If not as specified, replace the key reminder ...