Never use plain tap water, it will freeze in cold weather and block the washer jets. It also doesn't clean effectively, especially for road grime and insects. Always use a screenwash product.
What to Buy
- Ready-mixed screenwash, Pour straight in, no dilution required. Usually a blue liquid sold in 1–5 litre bottles (£2–8). Good for most conditions.
- Screenwash concentrate, Dilute with water. Mix roughly 1 part concentrate to 4 parts water in the reservoir. More economical.
- Winter/all-season screenwash, Important if temperatures drop below 0°C. These products protect against freezing down to -10°C or lower. Check the label for the minimum temperature.
Step-by-Step
- Open the bonnet.
- Find the washer fluid reservoir. It's a plastic bottle with a blue or white cap showing a windscreen/spray symbol. The reservoir is usually translucent so you can see the fluid level.
- Remove the cap.
- Pour in the screenwash, directly from a ready-mixed bottle, or pre-diluted if using concentrate. Fill until the level is near the top of the reservoir.
- Replace the cap firmly.
- Test the washers by pressing the washer stalk on the steering column.
What NOT to Use
- Plain tap water, Freezes at 0°C, leaves mineral deposits on the screen, and doesn't clean well
- Washing-up liquid, Foams excessively, smears the screen, and can damage wiper blades and washer jets over time
- Windscreen de-icer spray, Not a substitute; the jets aren't designed for aerosol products
MOT note: If the washer fluid reservoir is empty and the washers don't function, this can contribute to an MOT failure under the 'driver's view' category.