Ugh, that sucks. Shame you can't just disconnect the relevant circuit and operate the door locks manually.
Tried that first, of course.
I thought the same thing, but the entire safety feature system is interconnected, with seatbelt detection, brake and running lamps, door "ajar" detection, airbags, windshield wipers, warning lamps in the dashboard, and even the anti-lock braking system is controlled by this little black box of shite. The computer works all the time, that's no problem, but it's gone nuts and it operates things when it should let them sleep. It is the activation of the relays for the locks and the interior lights which is running down the battery.
If I want wipers or brake lights, I have to fix the little brain that makes it all work. This was my final conclusion after some troubleshooting and the mechanic (good guy, known him for years. He knows I am a car-keeper and that he does not have to get rich off me today. I trust him.) confirmed it today, but I have a case of "stickershock", just the same.
... and I repeat 
It's better to try and have something fixed on your car ASAP instead of waiting or it will get expensive. Same as letting other things break down on your car and not having it fixed, it all adds up. But sometimes people have no choice. People have let their cars run to the ground because they couldn't afford to have it maintained. I knew someone at work who did it to his Nissan Maxima and I took the "run to the ground" phrase literal and then he told me what he meant by it when I kept questioning him about it like asking him how did he run it to the ground, we drive our cars on the ground, did he drive it into a ditch or something.
Nah, mine's not like that, but you're absolutely right. It is a very well maintained car, even though it is ten years old now. I would not hesitate to jump in and drive across the nation in it, normally. It's just that something electronic broke on it and the parts are very expensive. Honestly, it took about a month to figure out what was happening, because it only had the problem occasionally. The first time I took it to the mechanic, thinking that my battery was bad (I bought the battery new last winter), he could not find anything wrong, either.
Electronics can be like that sometimes.
