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. Inspecting and Changing Fuses
Turn the ignition switch to LOCK 0*1. Turn headlights and all accessories off.  Remove the fuse box cover.  Check the large fuse in the engine compartment. ► If the fuse is blown, use a Phillips-head screwdriver to remove the screw and replace it with a new one. ...