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. If the Low Oil Pressure Indicator Comes On
Reasons for the indicator to come on Comes on when the engine oil pressure is low.  What to do as soon as the indicator comes on  Immediately park the vehicle on level ground in a safe place.  If necessary, turn the hazard warning lights on.  What to do after parking ...