Washer weirdness

[Benmac]

Got an issue with the windscreen washer on the wife's C43 estate, it's a little puzzling so just wondering if anyone has an idea.

SO, washers been getting steadily weaker over recent couple of months. Got to the point they basically don't work other than a dribble. As such, I diagnose it's not actually blocked. Bit of investigation and turns out this isn't uncommon. There's a filter on the pump that gets gunged up. Bit annoying as I've only ever used decent screenwash in it but hey ho. So, wheel arch liner off, pump out, filter out and yep, covered in snotty gunge. Give it all a clean, flush the tank a bit and get some more "snot" out. Put it all back together and yay, working washers again. Great.

That was Sunday. I drove it today first time since fixing and they're not working at all! No sound of the pump working and just nothing.

So, before I pull it apart to have a look does anyone have an idea?

- Wondering if I've dislodged some gunk and that has properly bunged it up but surely the pump would still function?
- I did flush it a lot with warm water on Sunday before refilling with screenwash. As such wondering if the concentration is poor and it's just frozen (it's -4 apparently here). Still no joy after a 25 minute drive though so you'd think it would un freeze by then.
- Coincidence that the pump has just decided to die.

[OllieJolly]

Barring any fuses etc, my first suggestion would be to pull the pump and, if you can, test it.
It's possible the gunge was causing it to be worked harder and it has finally given up, but even if not you can at least go from there.

[Disco_Biscuit]

Usually pump blocked with gunk, just needs taking out and cleaning, we do this daily at Mercedes dealership. Usually non OE screen is the culprit.