See also:

Extreme Cold Weather (Below –20°F Or –29°C)
To ensure reliable starting at these temperatures, use of an externally-powered electric engine block heater (available from your authorized dealer) is recommended. ...

Door Latches
Check for positive closing, latching, and locking. ...

1997 Jeep Wrangler review
A two-inch layer of ice is covering Hades this morning. Must be, because a few years ago after driving a Jeep Wrangler and commenting that even Mother Teresa would find fault with this vehicle, Ch ...