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. VSA Modulator-Control Unit Removal and Installation (Except Natural Gas models)
413170 Removal 1. VSA Modulator-Control Unit Assembly 1. Turn the ignition switch to LOCK (0). 2. Disconnect the 10 mm brake lines (A). ...