This isn't perfect, but it should help someone. Most cold weather Crank issues are fixed at step 1 or 2. Though a badly rusted Jeep with a bad starter could run you though the entire list
-Ron
Basic No Crank Diagnostic Chart.
Do the Lights work on HIGH? NO >> Check Battery Connections, and Battery <Redo Step>
YES
V
V
Hit the key: Do the lights still work? NO>> Recheck and
Clean Battery Connections <Redo Step>
YES
V
V
Check the connections at the starter, from the Fire Wall to the Engine.
Does it crank now? No >> Fix Connections <Redo Step>
Yes
V
V
Replace Starter
Did it fix it? NO >> (Skip Down **)
YES
V
V
Happy Days!
(**) Something very basic is missing here.
Check for voltage at the starter big lead to engine ground.
Check for voltage at the solenoid when someone turns the key to start.