1999 Cherokee Classic. 4.0, AW4, 4wd

I’ve got a very confusing/frustrating problem with my jeep. Yesterday as I rolled up to a stoplight, it shut off. Check engine lit up and it also gave me a no bus message, all my gauges also went out. Changed the CPS thinking that was for sure the issue, but it wasn’t. Did a little bit of checking and found fuse 11 (run/ignition) in the passenger side kick panel was blown. Popped another one in and it fired right up, but as soon as I put it in drive, blew the fuse again. Next, I unplugged the TCM, replaced the fuse, started fine and went into drive, but shut off in reverse. Then it got even more interesting… as soon as I turn the key to run, the fuse blows. I’ve unplugged every sensor and electrical connection (including PCM, TCM, NSS) on the jeep and the fuse still blows as soon as the key turns to run. The only connector that changes anything is the 12 pin connector below the NSS plug next to the dipstick. When I unplug it, the fuse doesn’t blow. I’m completely stumped on the issue. Obviously there has to be a direct short somewhere, but does anyone have a good place to start? Both ends of that plug go into the main wire looms that head back to the PCM, so it seems unlikely for there to be any broken wires in there I would think. Any help is greatly appreciated. I’ll post a picture of the plug I’m talking about.

 

Fuse 11 powers a lot

Here a thread (and some reading) incl wiring diagrams to give you an idea

https://www.cherokeeforum.com/f2/kee...203677/index2/

 

I left everything unplugged last night after it got dark on me. I went back out today and started plugging things in to see when the fuse would blow. I got everything plugged back in and never blew the fuse, and the jeep starts and runs like it should. I found 2 bare wires (both grounds) as well as a bare wire that was spliced in to another wire in the steering column. Other than that, I don’t know what fixed the problem, but it seems to be fixed (for now).

 

Have you fixed those wires?

 

Yep, I taped them up

 

Let us know how you travel

 

I have a 96 wiring harness and I'm trying to use a 2000 PCM. I understand that there are 3 coil driver provisions with the 2000 PCM. Is it possible to wire those 3 drivers together with inline diodes to get the coil to fire for all cylinders. I have looked over the entire pinnout for both pcms and this is the main difference.
Thanks

 

I’ll give an update in a few hundred miles, hopefully a good one 😆

 

I suggest you start a new thread for this.

 

Been running it a few weeks and everything seems to be solved for now