The plug is made integral with the washer fluid level indicator.
Recommendation. In winter, use only low-freeze windshield washer fluid. Freezing fluid in the windshield washer system can lead to component failure and system failure. In summer, it is better to use special summer windshield washer fluids. Their washing power, especially in relation to organic compounds, is much higher than that of plain water.
Then fill the windshield washer reservoir with fluid in accordance with the recommendations above.
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