Wiper fluid error constantly on

Hello Škoda owners.

I have 1.6 diesel 7-DSG model, 2018.

Pretty happy with my white shark, until recently.

I got the wiper fluid error which I promised to get around to filling. Of course, I forgot. We had a bit of a crap weather, with filthy roads, so I ran through the liquid pretty quickly. It got to the point where I fully emptied the tank at one point. That evening I stopped at a gas station, topped it up with 2l of wiper fluid, the winter type of course. The light remained on. I thought, screw it, it probably needed more, I know it's 3l capacity. Next day I bought the big canister, 5l, managed to get almost a third of it in, up to the fluid cap. I started the car, the warning light and error still came on.

I figured it's time to ask for help.

I drove to my local garage yesterday thinking it was a sensor issue. They called me to tell me that they removed the whole canister. First, the sensor comes together with the canister, it is not a separate part, meaning that should I want to replace the sensor, I'd have to replace the whole canister. The sensor was clean, eliminating our first assumption, that it was covered with gunk when I allowed it to get fully empty.  Second, all tubes were fitted tight. All wiring and connectors were clean and sitting tight. They even tested the sensor after they removed the bottle. They scraped the surface a bit to make sure that it was clean. Basically, whole system is fine, should be fine. They connected the car to the diagnostics, cleaned any error  codes. There were no codes of note anyway.

Today I tried removing the car battery and leaving the car like that for like 5-10 mins, to see if a total shutdown would make for a "restart" of the car, at least the software. Again, no - the error still comes up when I turn the car on. I get one ding, the error message, and a constant yellow triangle with exclamation mark warning light.

Any ideas guys? What else could I try?

Edited 22 January, 20251 yr by Poremetej