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 Coolant
Check the amount of coolant in the reserve tank.  If the coolant level is below the MIN mark, add the specified coolant until it reaches the MAX mark.  Inspect the cooling system for leaks. Engine Coolant WARNING Removing the reserve tank cap while the ...