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 Brake System Indicator (Red) Comes On or Blinks
Reasons for the indicator to come on  The brake fluid is low.  There is a malfunction in the brake system.  What to do when the indicator comes on while driving Depress the brake pedal lightly to check pedal pressure.  If normal, check the brake fluid level the ne ...