01' VW Jetta electrical problem

I just replied to another chap that was experiencing the same issue. You have a draw on the system that could run from a bad ignition switch to a failing component or accessory in the car. Isolate the problem. Kind of tedious work. You will probably notice that there is a spark with the car off and lifting the positive cable of the battery. There should be a spark but it should be very small. Isolate the fuse that reduces the spark and hunt down what is on that fuse.

The altinator charges the battery, inside the altinator is the regulator, if the altinator goes bad then it could drain the battery. It can be checked at a garage or automotive store ex. Auto none there could also be something drawing the battery when the car is stopped. Check to see if anything stays on when you shut the car off.