So Christmas eve I did some errands in the jeep. It started instantly as usual before my first stop and second stop. I put about an hour of highway driving in and got to a grocery store. When I tried leaving the jeep wouldn't crank. Turn the key, radio and dash lights all come on and I can hear the relay click in the junction box. There was no attempt for the vehicle to turn over and this battery is maybe 6 months old.
I tried cycling through the park and neutral positions, I cleaned my nss this summer, never had any issues until now so idk there, no changes with this common issue.
I got a friend to come and try jumping me, hooked up and tried cycling the key once and nothing, repositioned clamps and tried again and it fired up instantly. I drove it home without any hiccups.
I have not tested voltage to the solenoid, or tried restarting since its been home. I have not checked cables yet.

Once the vehicle was running I putting a meter to the battery and the alternator is working well.

At this point I'm a little lost on where to start looking. I do have an intermittent airbag light which makes me curious if the ignition switch is starting to go?
Otherwise maybe starter solenoid?

Anyway I did look for a write up for a no crank because I wanted to make sure and diagnose this in the proper order, so thats what I'm looking for. Where do I start and in order how should I proceed from here?


Thank you

 

As a place to start do what you said you haven't done yet. All the cables, clamps ,and connections including those to the starter. If that doesn't get next time it doesn't crank try, carefully, jumping the terminals on the starter... could be the starter.

 

ok, I went through cables. Tried starting it once yesterday and it fired right up. Tried just now and nothing, again. I tried jumping the starter as well with no luck. I went under to give the starter a wack and there is a small plug/wire coming from the solenoid. The piece that screws into looks to partially be soldered on to a piece that goes into the solenoid. This tab for the solenoid wiggles considerably compared to an old bad starter I have laying around. Any how I wiggled the cord to see if it was Clipped in and it is, then I tried starting and she fired right up.

Safe to say I need a solenoid?

 

I took that starter in and one I had laying around. The old one passed a bench test and the current one that was installed had the gear jumping back and forth. Ill install the " functioning" one tomorrow and report back. Generally I wont take a part store test as gospel because I once brought a starter in, that was bad and watched it pass before, then it started to smoke haha.

 

The solenoid failed in 3 Jeep starter motors I did

You can try swap the solenoid from your old starter, or they can be bought separately

 

Replacing the starter has resolved the issue!