Vios Windshield Washer Heater Issue

Interesting. I've got a Vios as well, though I can't remember the year right now, and I had a similar issue last winter. I would check the cable and plug connection to the heater first. That's usually the culprit. Give them a wiggle and see if that changes anything. Also, have you checked the voltage at the plug to make sure it's actually getting power? A multimeter would be handy for that.

Good call on the plug connection! Where exactly is that located? Is it easy to get to, or do I need to remove a bunch of stuff to reach it? And about the voltage, what voltage should I be looking for? Sorry for the questions, but I'm trying to avoid a trip to the mechanic if I can.

Okay, so on mine, the plug for the washer heater is tucked up near the base of the windshield washer fluid reservoir. You might need to remove the reservoir to get a good look and access to the plug. As for the voltage, you should be seeing around 12V when the windshield washer is activated. If you're not getting that, then the problem is upstream somewhere. Honestly, if you're not comfortable poking around with a multimeter, it might be worth taking it to a workshop. I ended up doing that, and they found a corroded wire in the harness. Cost me about 95€ to fix.

Thanks a bunch for the info! I'll check the connections and voltage like you suggested. If that doesn't work, I'll take it to a workshop, like you ended up doing. At least I have a better idea of what to tell them to look for now. Really appreciate the help!