Honda Civic Service Manual: Battery System

Electrical

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Battery Removal and Installation

Removal 1. Battery Terminal - Disconnection 1. Make sure the ignition switch is in LOCK (0). ...

See also:

Honda Civic Owners Manual. To Clear the System
Pairing codes, paired phones, all stored voice tags, all speed dial entries, all call history data, and all imported phonebook data are erased.  Press the button or the button.  Rotate to select Phone Setup, then press .  Rotate to select System Clear, then pr ...