tjwalker

Code 12 is strictly informational. Tells you that battery has been disconnected lately. It does not indicate ANY problem.

tjwalker

The alarm system could still be in play here. I think I would try disconnecting or disabling it and see if that resolves this.

DaddyCat

First page of OEM Cherokee Tech is a "sticky thread" called "Great Info Threads in Here". Second post shows OBD-I codes. It's still Possible your battery is not good, cables are bad, grounds need cleaning.
Jeepinbush, how did you check your battery and cables?

Jeepinbush

ok i've changed out the plugs, plug wires, coil and it still does the same thing. ive tried everything above and nothing changes can it be the factory alarm not disengaging all the way? im out of stuff to check for.. cacn it be my computer that is bad cause it did get wet but i opened it up and it looks waterproof..

DaddyCat

I have asked you again and again to describe in detail how you are checking things and you never give details. I give up, if you work on your jeep as poorly as you answer questions it's no wonder you can't get it running. I'm done here.

Jeepinbush

i checked my battery cables by taking them off and cleaning the area where it connects to and i check for any rust/dirt. i jumped both plugs that plugs into the ballast resistor it still didnt help.i had a good battery to start with and now it dead from cranking it so much so i got to charge it. i switched out the plugs/plug wires for new ones. i bout a new coil and new shut off relay it still didnt work. i spliced into the green/orange wire thats suppose to be from the alarm and grounded it and when i plug the battery back on the lights are not flashing no more, so i tried to start it and it still does the same thing by starting up for a second and shuts back off. SORRY FOR NOT EXPLAINING IT CLEARLY I WAS WRITING FROM MY PHONE.

Jeepinbush

Thank you guys who tried to help.i got my jeep running again.i don't know how but I unplugged the computer for a second time and it fired right up I don't know how though.

bonesjones83

I have a 99 XJ Sport and it's doing the same thing! However, when it starts then stalls the engine light comes on along with the key symol and a "no bus" code on the odometer. This happened in the past and I had to replace the ECM. I don't have a lot of money to buy a new ECM again! One of the codes it's throwing is for the neutral safety switch. I bypassed this and wired lights direct to a switch for backup lights. I've ran it that way for a few months then one morning it cranked but then stalled 3 sec. after starting. Any ideas? I'm frustrated and want my jeep running so I can put my 34 swampers on and other mods! Please help! Thanks!