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. Emergency Engine Stop
Models with smart entry system The ENGINE START/STOP button may be used to stop the engine due to an emergency situation even while driving. If you must stop the engine, do either of the following operations:  Press and hold the ENGINE START/STOP button for about two seconds.  F ...