Hi.. our 2014 Prius V leaks all the wiper fluid out within a few minutes after filling it. Our mechanic spent the better part of the afternoon looking for a leak. There was none to be found. We use vinegar in the water, and there’s no odor in the cabin. any thoughts?
My thought is your mechanic should have just taken out the reservoir and find the leak by attaching a smoke machine to the line. Assuming it's not the reservoir itself. The rear wiper gets fluid from the front and goes through the hatch. He could pinch off the line going to the back to narrow down the search. It holds a gallon of fluid, it has to be going somewhere.