weird transient warning light Prius 2008

Hello, I had a transient warning light appear on my 2008 Prius during a recent drive from the Portland, Oregon area to Seattle . The reason I'm posting this is that this icon isn't listed in the owners manual, nor does it come on when you start up (boot up) the Prius. Also this warning is on the same line as the "ready" and air re circulation icon. On the right side of the display ( the usual low pressure tire, and I think traction control warning icons are on the line below). This occurred about 135 miles into my drive at the infamous Interstate 5 as you enter Tacoma, Wa ( stop and go traffic) the icon is yellow /Amber a box with 3 yellow squiggle lines which are vertical and cross just past the bottom of the box. After about 15 minutes the warning light went out. It never came back. I have 115k miles and car was recently serviced. I wonder if this is some air flow / ventilation warning. I am overdue to check cabin AF but am unaware there would ce a warning for that. The AC seemed just fine and no effect on the cars performance. Weird.

 

No there are no words, just the icon itself. Also again icon is yellow square with 3 squiggle lines coming out of it downwards

 

Wow that's it! I feel silly now. It was a very mild winter last season and record warm temps now.... In any event I almost never use the rear de icer as it's mostly rainy in the winter here. Why it would trigger on (honestly the only way would be hitting on steering wheel by accident as touch screen takes deliberate action.most likely I pushed the button on the steering wheel by accident and the circuit just timed out to prevent electrical drain! Thanks!