The audio system is disabled when it is disconnected from the power source, such as when the battery is disconnected or goes dead. In certain conditions, the system may display a code entry screen. If this occurs, reactivate the audio system.
Reactivating the audio system
1. Turn the ignition switch to ON *1.
2. Turn on the audio system.
3. Press and hold the audio system power button for more than two seconds.
The audio system is reactivated when the audio control unit establishes a connection with the vehicle control unit. If the control unit fails to recognize the audio unit, you must go to a dealer and have the audio unit checked.
Honda Civic Service Manual. Audio-Navigation Unit Removal and Installation ('13)
1.
Dashboard Center Pocket
1.
Remove the screws (A).
2.
Remove the dashboard center pocket (A).
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