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. Resetting the Display
Reset the maintenance minder information display if you have performed the maintenance service. Turn the ignition switch to ON *1.  Press the (display/information) button repeatedly until the appears.  Press the ENTER button.  Press and hold the ENTER button fo ...