Can I directly add antifreeze windshield washer fluid when there is still some left in the car?

[Sophie]

It is acceptable to directly add antifreeze windshield washer fluid when there is still some left in the car. Windshield washer fluids can be mixed, but this will raise the freezing point without causing other adverse effects. Precautions for using windshield washer fluid are as follows: Pay attention to the vehicle's operating environment: During vehicle use, there can be temperature differences, such as between southern and northern regions, which also affects the requirements for windshield washer fluid. In northern winters, the fluid needs to have certain antifreeze properties. If the antifreeze performance is poor, the fluid may freeze in the container and become ineffective. Use the same product for an extended period: Each manufacturer designs and develops their windshield washer fluid differently, and even if certain additives serve the same purpose, their quantities may vary. In the vehicle's wiper system, impurities can inevitably precipitate. If you switch from one product to another, more impurities may form and settle in the wiper system.