Not every time, but a lot of times, when we've had lower overnight Temps (lower 20's and less) I have electrical issues. It's almost always the defrost fan won't blow, sometimes it's the lights, sometimes it's the blinkers, sometimes it's something different, and sometimes everything works fine. And it doesn't always do it. There's no pattern to it. Once the truck gets warmed up, everything works fine. I've done a few basic checks, but I didn't come up with anything, but I'm not all that automotive electrical savvy. Any ideas?

 

Check the grounds under both kick panels