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 Service Manual. Taillight Removal and Installation ('13-'14: 4-door except Natural Gas models)
1. Trunk Floor Cover 1. Fold down the seat-back(s). 2. Remove the front area of the trunk floor cover (A). ...