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. Outside Air Temperature Indicator Calibration ('12-'13, '14: 4-door)
1. Front Grille Cover 1. Remove the front grille cover (A). ...