Man, my Mazda3 does NOT like the cold.
Whenever it drops below -20C (which this winter is ALL the freaking time), the left turn signal stops working intermittantly. As in, you push it down to indicate a left turn, and the signal just doesn't signal. Luckily, the '3-flash lane change' function still works (most of the time) so I can get around the issue by just holding the turn signal stalk in the partial down position to keep the 3-flash lane change going. There has been the odd time that even that doesn't function - that's awkward when I'm trying to make a left turn at a busy intersection. And yet, it truly is intermittent. For example, today, -33C, and the turn signals all work just fine.
BUT, I encountered another issue for the first time - the engine went into limp mode. So I'm trying to merge onto my local arterial hwy (80km/h speed limit) to get back to work after dropping my kid off at school. I'm accelerating in the merge lane, and then all of a sudden I lose all power - the car won't go above 30km/h - and the check engine light starts flashing. I immediately pull over, turn off the car wait a few seconds, then restart it again. The car starts up just fine, and behaves completely normal.
I know a lot of problems like this can be caused by a weak battery - but the battery was tested by my mechanic last time the car was in for an oil change, so I doubt that's the issue. At this point, I'm just going to chalk it up to extreme cold weather, and see if it does it again.