Cold weather preparedness.

I can't really see how heating a small proportion of the screen wash tube via the engine helps. You still need additive to prevent freezing overnight and only a small section is actually heated, so you spray cold / hot / then cold again as you pump the tube out, so not even a hot wash (which can help).
​​I Had a VW with heated spray nozzles, I guess the plan was to help with it's frozen extremities on very cold nights as  nozzles can "air freeze" even with additives.
Could be wrong with my reasoning, just thinking about it as I actually like the solution/ heat exchanger used.
 

In my experience it is the nozzle that needs heating, not the liquid, as Mike says it can freeze even with additives.

Pity they don't make them for the Jimny, unless you can get them for another model that are the same size?

There are generic ones on eBay that you wire up. Don't know how hot they get or how much cutting would be involved. Also don't underestimate the level of heat soaking that the washer bottle will get living on the hot side of the engine bay given how hot it gets under the bonnet on a relatively short run in a Jimny.

The nozzle freezes, because there the additives (usually alcohol) at the end of the nozzle evaporate and the remaining water freezes. So heated nozzles would be great.

Ford fit/fitted heater nozzles to some models. They were permanently wired through the ignition circuit. Last night was -7 deg. C and my nozzles were frozen. This is not the washer fluid but frost on the outside of the nozzle.
I wont to reiterate my previous comments. My experience goes back many years to my rallying days when we tried wrapping polythene tubing round a heater hose but found it only marginally effective. I have experimented with various systems including a 16ft double coil of copper brake pipe that ultimately proved OTT until I found that my present system proved effective and simple. The fact that it resembled the system used by Saab is purely coincidental but pleasing that they also consider that it is suitable for Swedish winter conditions.
So there you have it, I find the system works for me, know it's up to you.

Roger

Roger, that looks to be a really well-made assembly, nice work. If you decide to put them "in production," put me at the top of the list. (Seriously.)

I think if people did the maths on the fluid flow of a windscreen washer pump vs the output of an electric heating element, they would quickly understand why drawing the heat from the engine is a far superior solution to trying to heat the fluid electrically. (Heated nozzle tips being another matter, solving a different problem requiring less heat energy.)

Really impressed with the ingenuity, and particularly with the level of finish of the part in the photo. Thanks again for posting.