Jump to content

Truck won't crank

Recommended Posts

So i'm pretty confused by this.


Turn the key, You hear the solenoid clank in the starter, But doesnt even try to turn over.


Battery reads 12.5v been driving it all day just fine, Started fine all day, No struggling sound etc.


Tried P & N on the shifter, just incase.


Did it earlier today & Then finally cranked over normally without issue. Got home & now it won't crank.


Starter is less than a year old.


Any tips what to check first, Before i rip the starter out?




think it might be the wiring to the starter. Wiggled it a bit & now the truck starts about 50% of the time i turn the key over.


can't climb under it till later, Its raining pretty good out lol

Link to comment
Share on other sites

Bench test the starter first. I have had them die within a year.


You have to remove the starter for this, Right?


I believe its still under warranty though, Which is good.



Might be loose connections to the starter...

Thats what i was thinking after it 50-50 started when i wiggled the wire, I stuck my hand under there & They were solid to the starter.

Link to comment
Share on other sites

Neutral Safety Switch?  There's a good writeup on this site about how to remove and clean it.  Can be a bear removing it, read up and have patience.

Its an Auto.



You can jump the solenoid with a screw driver to test it. It is best to remove it and test it. It is only a 10 minute job.


True, I just don't have a shop/dry area to climb under it currenty


Rainy season here in washington lol

Link to comment
Share on other sites

Automatics also have a neutral safety switch. Do a search for jeep aw4 NSS. They don't seal out the dirt so well and eventually get too much crap in them and quit working. A new one's a couple hundred dollars, cleaning it out takes a half-hour, most of which is spent removing and installing it.


However, if the NSS was bad, you would get absolutely nothing from the starter. If the solenoid's making noise, the starter trigger wiring (including NSS) isn't the issue.

Are your main battery cables in good shape, i.e. not corroded? Check the bolt where the negative cable goes to the engine block.


There are three terminals on the starter solenoid, two big, one small. It grounds through the mounting point. The small one is the trigger wire. When properly grounded with no positives hooked up, putting power to it triggers the solenoid, which engages the starter gear and connects the two large terminals. With no power anywhere else (but still grounded), putting power to one of the larger terminals, one won't do anything and the other will spin the starter motor. The positive battery cable should be hooked up to the one that does nothing. With the positive hooked up that way, putting power to the trigger (small) terminal will trigger the solenoid, engaging the drive gear and sending power to the motor, cranking over the engine. This is basically the bench testing procedure. It can be done just as easily in the truck, bench testing means testing on the work bench, i.e. not in the truck. The only difference is you have to listen for the engine cranking to know it's working instead of watching the drive gear engaging and spinning. Just if you do it in the truck, make sure the truck is in park or otherwise won't start moving, especially if there's someone underneath.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Create New...