Plymouth - Breeze :: 1997 Intermittently Starts - None Of The Electrical Came On

My Plymouth Breeze is having issues starting up. It started a while back, my wife was driving the car and she got stranded because her car wouldn't start. I gave her a jump. I had the battery and alternator tested and the battery was bad, but supposedly that alternator is good--so I replaced the battery. We get a week or twos use out of it, and the the rear brakes sprung a leak-- so I replaced the rear brake lines. When I tried take the new brakes lines for a test drive the car wouldn't start. I have a battery charger and used the 50 amp start feature, the car would still not start (it would turn over but not start). So I gave the battery a deep charge from the battery charger and the next day it was fine. My wife used it for a week and all seemed well. That is until the other day where she tells me it has a new problem.

Apparently the defroster randomly turns off and on, and the vent constantly switches which direction it is blowing. She took it out for a drive while it was like this and got stranded again. I went to give her a jump and the car wouldn't start at all. In fact none of the electrical came on, it was as if the battery had been disconnected. So we eventually get the car towed, and as I put the key in the ignition to put the car in neutral I hear the beeping to indicate the car door is open. I tried to start it and all of the electrical shut off again. So the guys tows car back, having to push it into a parking spot. I realized the tow truck driver left the keys in the ignition and it just occurs to me he had rolled the window down. I get in the car and turn the key and it starts up without hesitation, like there were not problems at all. Needless to say I'm a little confused and frustrated with this car. I'd like to get another year or so out of it before I replace it.

So here is what I am thinking...Battery: This should be fine I just replaced it.Alternator: I had it tested coupled with the last scenario leads me to believe this probably isn't the problem, but is suspect.Starter: This seems to work when there is power, so I don't think that is it.Fuses: They either work or they don't, there is no "getting better" so I doubt it is a fuse.Computer: I think this might be the culprit. Before I had to give it another jump (when it wouldn't take) things were turning off and on at random. It is also the only thing I can think of that might act in a fickle way.

Another theory is a loose wire coming off of the battery.