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. Keys
Use the key to start and stop the engine, to lock and unlock the doors and to open the trunk. You can also use the remote transmitter or smart entry system* to lock and unlock the doors and to open the trunk. Smart entry remote* The built-in key can be used to lock/unlock the doors when ...