Drove the jeep to the store to get some chow. Hopefully going hunting in the morning. Came out of the grocery store, and the jeep didn't start (didn't turn over, nothing, like a total electrical failure. One of the idiot lights was glowing weakly. Turned the key off, everything lit up. Tried again, same result. Pulled on the headlights, they came on (bright), then tried to start and it started. Drove home. Turned off, tried to start, same deal. Now the jeep acts like it has no power at all, for several minutes at a time. Is there a power control relay somewhere? Battery voltage is about 12.7 VDC. Drifts down to 12.4 or so when I can get power on. Checked all the fuses, swapped the starter relay. Not really sure where the problem is. Perhaps in the steering column?
Bad battery? Jeep usually sits all week, I drive it on weekends.

 

Sorry for the lack of detail. 2001 XJ Sport. I have a winch installed, with a Putco headlight harness, all within the last month. Otherwise stock electrically.