TSS dash camera fogging up

Yes, that has happened more than a few times on mine. I just used the front defrost to dry it out. it is a temporary thing. That being said, I do remember a thread on auto high beam malfunction in which someone took the housing off of the forward-facing camera and cleaned the inside of the glass. I didn't feel that was necessary but if I find the thread, I will post it here for a reference.

EDIT: I found the comment on how to remove the forward-facing camera housing and clean inside by @liquidtenmillion.
Automatic High Beams Not Functioning? | Page 3 | PriusChat

 

Yep.

Common winter-time issue in every recent vehicle I've owned.

The best remedy for me is to place a packet of desiccant in every nook and cranny inside the passenger cabin. This includes door pockets, under the seats, glove box, ... even one inside the overhead sunglass compartment and behind both A-pillars. I replace the packets every two or so years just to be sure. We buy bags of these on eBay or Amazon for less than $10 and sure beats having a sock filled with critter litter under the front passenger seats.

Cheers