I've been having some strange problems over the past month or so and wonder if it's a computer glitch, and I'm hoping somebody may have had a similar experience and knows what is causing it.
About a month ago my wife called while I was out of town and said the battery had gone dead while she was having lunch. I'm pretty sure the battery was not dead at the time. Anyway, thinking the battery was dead she got a boost and while driving home all the warning lights on the dash started flashing at random so she pulled over and shut it off. Afterward it would not start and she had it towed to our mechanic (not a dealership) and dropped off. This was Sunday. Monday morning the mechanic called and said the battery was completely dead and after they charged it the Jeep started and ran fine.
About a week ago, I had an experience where it would not shut off. I turned the key and pulled it out and the engine kept running. The first couple of times I just stalled it out. The third time I decided to let it run and see what happened, so I put it in neutral with the parking brake set, locked the doors and left it. When I came out of the store about 30 minutes later it had stopped running and that problem hasn't occurred since.
Yesterday we drove to the ski hill and parked around 10:00am. Came back at noon and started it up while we ate lunch then shut it off and left. When we came back about 90 minutes later it would not start, not even a click. The battery didn't appear to be dead as the electronics (radio, fan, etc) were all working, but when I turned the key there was absolutely nothing. I kept trying it (turn key... nothing... turn it back... repeat) and eventually it kicked over briefly. Continued trying it and eventually I got it to crank and start but died immediately. Kept at it and finally it started cranking and I got it running but it seemed like it wanted to die so I kept the throttle on and revving around 2500. We started driving home but the dash was going nuts, warning lights flashing, tach and speedo swinging wildly. Initially the temperature gauge was working but at some point it stopped. We were able to drive all the way home (about an hour) but when I shut it off it wouldn't start again. I checked the battery when I parked and it was 12.75V. This morning I went out to see if it would start and it would try but wouldn't turn over. I checked the battery again and it was down to 9.75V. There were no lights left on overnight.
This is a mostly stock '08 Rubicon Unlimited. I've changed the bumper and tied in the included marker lights using the manufacturers wiring harness and relays. Also added a winch, again using the manufacturers wiring harness. I don't think this would cause the problems I'm experiencing, and the problems didn't start when those additions were made.
I took some video of the dash behavior. You'll notice that the tach is reading 0 sometimes but the engine was always running between 2000 and 2500 rpm. Same for the speedo, we were driving between 80 and 100 km/h.