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. Rewriting the ODO Data and Transferring the Maintenance Minder™ Data to a New Gauge Control Module ('13)
1. HDS DLC - Connection NOTE: For specific operations, refer to the user's manual that came with the Honda Diagnostic System (HDS). Make sure the HDS is loaded with the latest software. ...