xacto rocker

Wont start with key
hey my 92 Cherokee 4.0 4x4 still will not start with the key. Tested power and grounds from starter relay, battery power into relay and wiring from relay to starter are good. Manually giving power to relay output wire will crank engine over. Testing power and ground wire for relay control shows the two wires to be shorted together. The power wire from ignition switch makes connection to ignition switch and also connector at neutral safety switch. Wire that is supposed to connect relay to the neutral safety switch is open. Ohm testing the neutral safety switch in park and neutral position show to have high resistance.
this is the testing I have already done. Do y'all have any ideas where I might need to look next I'm no really sure where to look next I can't think of where the power goes other than these places that would cause this. Thank you

Saudade

Did you try shifting in neutral to start? Also move the shifter through the full range a few times.

The starter relay (coil side) grounds through the NSS when the shifter is in P or N. If the wire from the starter relay to the NSS is open, then that's the problem. Looks like it's a Brn/Yel wire. The Blk/Tan is the ground. Make sure you're testing the correct (matching) pins. You could also test for voltage on the harness side of the NSS. Should get 12v with the key to START. If not, verify 12V at the relay end. If so, there it is.

xacto rocker

Ok so yeah I have had this issue for the past 4 years I just have a push button under the dash right now. I finally have some time to mess with it so yeah I will check what you said thanks.

xacto rocker

so it looks like the neural safety switch is functioning correctly and I checked the for continuity and its where it should be. only weird thing was when I bridged the two pins it has like 7 volts or some weird between with with key on. but it does look like I have a short somewhere in the harness. since I have pretty much zero voltage at the relay or switch connector while cranking. I'm guessing behind the fuse box might tackle that another day I hate pulling fuse boxes always mess something up.

BillyBoy

Start with the 2 main wires going to the fuse box. Clean and reattach them. Along with the Body to Battery wire. If they're weak, even to a certain amount, itll.cause all kinds of issues.


Hook jumper cables to your conns on the battery, fuse box, and frame. If it works, you found your issue.



Good Luck. God Bless.

BillyBoy

Even a Speaker Wire, with Alligator Clips will work for testing this theory out.

xacto rocker

Ok so what you saying is to just clean grounds and I'm not sure what you mean by the jumper cables? I have power from the ignition switch to the lower fuse box inside when cranking the vehicle but I don't have power going from the fuse fox into the nss wires or relay. what are you meaning with the wires? should I just give power to the two leads to bypass the nss switch and see if it cranks right up? then that would tell me there's a problem from where the fuse box is to where it comes out of harness in engine bay? thanks

lawsoncl

See https://www.cherokeeforum.com/f2/how...-96-xj-191405/

Bypassing the NSS will likely cause a error code for the NSS though.