Ignition switch is for contact purpose when you turn your car key. It has nothing got to do wheather condition.I suspect your battery could be the culprit. Wheather cold the battery could be dropped to less than 12 V DC or the current in Amphere is not strong enough to crank the car. Send your car to the battery workshop to have a check on the battery control before suspecting anything else. A car battery life will normally last between 1.5 to 2 years. Hope this help.