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. Locking/Unlocking the Doors Using a Key
If the keyless remote battery or the vehicle battery is dead, use the key instead of the keyless remote. Fully insert the key and turn it. Locking/Unlocking the Doors Using a Key When you lock the driver’s door with a key, all the other doors lock at the same time. When unlocking, the ...