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. Ignition Switch and Power Mode Comparison
Ignition Switch Position LOCK (0) (with/without the key) ACCESSORY (I) ON (II) START (III) Without Smart Entry System Engine is turned off and power is shut down. The steering wheel is locked*1. No electrical components can be ...