When extremely cold out, key fob does not work and car does not turn over?

How old is your battery? Older batteries tend to not have the cold cranking amps needed to start vehicles in colder weather. If it older than five years I would suggest replacing it.

When it happened the first time, we replaced the battery. The second time, service department replaced the ignition switch. Third time, they are stumpted.. maybe BCM??? they cannot check it unless car duplicated the problem again which it won't do now since it won't be below zero till next year.

2008 Trail Blazer.Will start every time in the fall, winter, and spring. Live in Wisconsin. Today it is dead and will not start. Same problem last winter. New battery makes no difference. John Paul dealership could not resolve the problem. They suggested I take it to a Auto Tech school and leave it there to see if they can figure out what is wrong with it! Really? Help! Jo Ann

meant to say it will start in the spring, summer, and fall. It never will start in the winter at all. Need to get a jump each time. Thanks!