I have an 05 530i. Just had it into the shop for an ignition switch ($650). Now my battery is draining very quickly. I'm pretty sure the car isn't falling asleep because the light is no near the shifter indicating the gear, and the light won't go off. I locked the car, came back well over an hour later and it's still on. No messages no idrive. Never happened until it was taken to the shop, shop owner refuses it was them and won't touch the car without a $300 diagnostic fee. Any thoughts on what it could be?