I would worry more about theft than winter temperatures for electronics. You can take a look at your owners manual to see if it gives a storage temperature range. In general if flat screens had a problem with freezing storage temperatures about 75% of the USA a all of Canada could've buy a TV in the winter. They have to get them delivered and that means trucks and they aren't heated.
Operating in freezing temperatures is a whole different story.
2008 Chevy Silverado 2500 Duramax Crewcab
Jeep Commander - sold
Flagstaff V-Lite WRB26