Honda Civic Service Manual: Engine Cooling

Engine

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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. Immobilizer System
The immobilizer system prevents a key that has not been pre-registered from starting the engine. Each key contains electronic transmitters that use electronic signals to verify the key. Pay attention to the following when inserting the key into the ignition switch or pressing the ENGINE ST ...