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. Checking the Engine
If the engine does not start, check the starter. Checking the Engine If you must start the vehicle immediately, use an assisting vehicle to jump start it.   Starter condition Checklist Starter doesn't turn or turns over slowly. The batte ...