PKSB flashing indicator frequently on - rainy conditions?

Welcome to PC. I just noticed your post. It's odd that I seem to be the first to respond after all these days, but here's my 2 cents worth. My wife's 2017 has that feature. A while back, we drove her car from central Ohio to eastern Iowa. Half the distance was in the rain. The light never flashed. It's been driven lots of other times in the rain. Never a hit of a problem. Something's definitely wrong with one of your sensors and it shouldn't be too hard for the dealer to chase it down.

 

I acutally have a 2019 AWDe XLE as well. it is true that it may go on during inclement weather. I always get it when I get excessive snow/ice. From what I recall though, the software turns that feature off for that trip (I thought). BUT doesn't rule out if you have an overly sensitive sensor. I'm assuming you are only getting this issue with ugly weather, but if this is happening at other times, it could be an issue. With dealers, they are going to push back on these types of issues, especially when it's part of the warranty period. You may have to continuously push them with this if they are resisting.

 

We live in Seattle, too, and have a 2020 AWD-e XLE. I have never seen that light go on, and we’ve of course driven quite a bit in the rain.

the backup camera though is worthless in the rain... of the half dozen vehicles I’ve owned with backup cameras, I never recall having issues with water on the lens as much as we do with the Prius. Poor placement presumably.

 

You might want to consult your owner's manual. I have 12 pages in mine that describe the functions and various (numerous) malfunctions of the PKSB system. In just normal driving around in clear weather I've seen mine blink and buzz when in close proximity to another vehicle with those little ultrasonic detectors on it. It also likes to detect my recycle bin stationed near the front drivers side of the car when I'm pulling in to my carport. It will give me distance estimates to the obstruction, which is interesting. The owner's manual warnings make it very clear that the sensor array needs to be kept very clean, and looking closely at a sensor I see an isolator ring around the sensor where dirt could accumulate. You might want to check all of those, especially up front where insect debris may accumulate.

 

I think the OP understands what the manual says, but is determining an issue of potential over sensitivity. Cleaning the sensors is one thing, but one cannot clean the sensors when inclement weather hits and you are driving and driving and still a ways away from your destination. I’ve seen these sensors cause flashing indicator during snow but never rain. What I think to do is monitor if this happens again and determine which sensor might be causing this flashing and see how often this occurs. If it occurs with multiple sensors, maybe decrease the sensitivity.