No start/crank

Hey guys I have searched up and down for help so please let me know what you think.

Last monday the 99 xj 4.0 auto 4x4 started and ran, now as of yesterday it will not do anything when the key is turned. You get in radio and dash and such, you can hear the fuel pump prime, but nothing when you turn the key, no crank at all on the starter. I took the starter to advanced and it tested good. So no I have replaced the crank position sensor and ignition module from the junk yard. Still nothing, I did take a screw driver and short the starter and it fires and turns the engine over (didnt old it long enough to make it start up). Now the only thing i can think left to try is cleaning the NSS (neutral safety switch) on the tranny but I have cleaned it up before and right now it wont start on any gear so idk. Any suggestions?? Thanks guys

It sounds like your NSS to me..My wifes did the same thing, install a push button to start it now..I'm to cheap to buy a new NSS..

Thanks I might just have to try cleaning the NSS, if that dont work ill get one from the junk yard. Thanks any other ideas guys

NSS seems likely, I remember having to clean the one on our 91 XJ when we first got it. I think it wouldn't turn over in neutral but worked fine in park. It was a problem because when we first got the 91 XJ it was stalling out on the road (CPS).

Did they make any major changes to the 99 models? I would be tempted to with the ignition on short the starter and see if it runs. Might not be a good idea though.

The other thing it might be is the Ignition Switch melted or shorted. They changed this in major way after 96 so it is probably different form what I am thinking. Maybe it is just the relay for the starter. I probably check that and swap it around with another one to test it.

Did they test the starter solenoid as well or just the starter itself? Have you tried the screwdriver trick with the starter?

yes i did try the screwdriver trick as my first post says, and it DOES fire the starter and turn the engine over.

I don't have a wiring diagram handy but there will be a starter relay in the underhood fuse box. If you look at the side it will show a small diagram. Pin 30 should have constant 12V power- does it? When the relay is activated by providing power and ground to 85 and 86 (not necessarily in that order, it doesn't matter which is which), the internal relay contact moves over and powers up pin 87, sending voltage down to the starter. Disregard 87a if the relay has it. You already know the starter works, so check the wiring to it by removing the relay and powering pin 87 with a jumper wire. This should crank the engine.

If that works then you either have a bad relay or an issue with the circuits tripping the relay- 85 and 86. One will be power, the other ground. The NSS will close one of those circuits and the other should already have what it needs be it power or ground.

PROBLEM SOLVED!! Well I crawled under the jeep to take off the NSS to look at cleaning it. Well once I got it off I found the problem, about 4in up the wiring from the NSS the wiring was CUT!, the wire loom was cut open and about 4 of the wires inside the loom were cut. Now it kindda looked like someone got under there real quick with a knife and cut it, because were this was nothing should have caused it. Plus like I said Monday it had started and then sat till Saturday when it wouldnt start. My younger brother has been driving the jeep so I wonder if he as made some enemy's. But I solder the wires back together and heat shrink them and all is good and workin. Thanks again guys

keep in mind there is an adjustment on that NSS....i dont know if you loosened it or anything in order to fix your cur wires.

What adjustment? I didnt open the NSS this time but I have before and cleaned it, dont remember any adjustment

theviper90210 said:

What adjustment? I didnt open the NSS this time but I have before and cleaned it, dont remember any adjustment

Click to expand...

You may have got lucky the last time you opened it up and cleaned it.

Adjustment of the NSS is discussed in this article.

http://www.jpmagazine.com/techartic...eep_cherokee_neutral_safety_switch/index.html

ahhh ok I get it thanks guys!