That's due to the memory circuits of the huge number of unnecessary computers. Unless specified otherwise by the manufacturer, 35 milliamps, (.035 amps), is all that's allowed for the "ignition off draw". At that rate, Chrysler says a good battery will start the engine after sitting for up to three weeks. Cadillac allows up to 50 milliamps for most of their vehicles, so you're close to the maximum number of days you can expect.
GM has had a big problem with their generators since they redesigned them for the '87 model year. It is common to go through four to six of them in the life of the vehicle. It's the very large voltage spikes they produce that destroy the internal voltage regulator and diodes, and they can interfere with computer sensor signals. The way to reduce the number of repeat failures is to replace the battery unless it is less than about two years old. As they age, they lose their ability to dampen and absorb those spikes.
In your case, consider replacing the battery with a larger one if you need to increase the amount of time the car sits unused. Doing that may also prevent a generator failure in the near future.
Tuesday, December 4th, 2012 AT 1:40 AM