I have a 2001 cherokee. Last Friday it hit -8 degrees outside and the car wouldn't start in the morning. A jump would get it to start then it would die if I wasn't revving. I just changed the alternator last year. With a new battery I tested my alternator and it seemed to be working. It worked for a few days and last night it wouldn't turn but had full battery power. Tried again this morning and same thing with full battery fun made no clicks or any sounds of turning. Any ideas?

 

Well, the same thing happened to me over the past few days. Temps down in the teens. I have all new starter, battery, alt, and many other parts.
1st day - Turn key the first time and it clicked once then nada. tried it again and it started.
2nd day - turn key, click no start, tried again, it starts...runs great
3rd day - turn key, click...nothing, tried it again 3 times...nothing! Crap! So, I turned the key, put it in neutral and it started right up. That was yesterday. Will see what happens today.

Neutral safety switch? Contacts? IDK? frustrating? YES!!!!!!