Have had my M6 garaged for awhile, just have been from home quite a lot lately. Went to go take it out and find I have a dead battery. I also don't have a mechanical key (just a fob with an uncut blank from when I needed a replacement once). Is there a place under the car where I can apply 12V to get it to unlock so I can then put the battery itself on a tender? I went under and looked like I could see a bolt on the alternator, but unsure if it's the main line itself or just a bolt but more to the point, I can't seem to reach it. Is there something I can do, or do I need to call someone to fish the door handle?