Diagnostic procedure
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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Mazda 6 Service Manual: Electrical troubleshooting tools
Jumper wire
A jumper wire is used to create a temporary circuit. Connect the jumper
wire between the terminals of a circuit to bypass a switch.
Caution
Do not connect a jumper wire from the power source line to a body
ground. This may cause burning or other damage to wiring harnesse ...