I am on my third XJ, I absolutely love the 4.0 H.O engine, but my latest jeep is giving me a problem i have never experienced. It started as a once in a while issue now its daily. So when i start my jeep sometimes it will go absolutely dead when i go to turn the key. I mean utterly dead no volts. I just put a reman. Engine in it and the engine is strong good volts from the alt but im sure theres a ground fault somewhere, maybe a door since my locks will lock and unlock by themselves repeatedly sometimes. I had installed an aftermarket stereo and found when i turned my lights on it would cause the stereo unit to switch to my back up cam screen. I haven't installed a cam yet though. Also i bought a code reader that links to my phone so i could root the issue out. But it found nothing. I have found it worse after raining so i sealed my windshield as my fuse box is directly below the leak. I have also found that if i disconnect my battery and my pcm after parking i dont have as many issues. Any ideas welcome.

 

I agree, you're problem is probably related to a ground issue. Clean the one between the engine and the firewall and where the battery ground lands on the engine block for starters.

 

I forgot to mention that my right signal operates normally but from often my left signal activates my four-way flashers. Im hoping that narrows my fault to the drivers side? 2000 xj sport

 

I had the same problem when I resurrected my jeep. After I turned the key to crank, I heard a click and all the electrical died like the battery was disconnected. To fix it (it took a while to figure out this was the problem) I cleaned the battery terminals and cables really well, and I have not had this problem since. If you tried this, and it does not work, I suggest finding all the grounds, and cleaning them with a wire brush, and getting your battery tested.

 

thats my next step, but i know theres a fault somewhere in the drivers door. I hope its there as ive found insulation cracked and exposed hot lines just by removing the boot between door and body. Im on my second battery in as many months. Ive patched the exposures i can see and still my door locks seem possessed.

 

Get yourself a 12 volt test light. Unhook the positive cable from the battery, hook one end of the test light to your red cable terminal and the other end to the positive battery post. Make sure everything electrical is shut off, doors are closed, etc. If the light is lit, you have a short somewhere. Take each fuse out one by one, if the light goes out, that's the system that has the fault. If the light dims, you found one fault, but there is still another.