Honda Civic Service Manual: Engine Cooling

Engine

...

Coolant Replacement (R18A9)

1. Radiator Cap 1. Wait until the engine is cool, then carefully remove the radiator cap. ...

See also:

Honda Civic Owners Manual. Security System Alarm
The security system alarm activates when the trunk, hood or doors are forcibly opened. The alarm does not go off if the trunk or doors are opened with the key, remote transmitter or smart entry system*. However, the alarm activates if a door is opened with the key and then the shift lever ...