A couple days ago I found the battery of the 420 SEL was discharged -
don't know the cause yet. It had not been driven for several weeks.
Luckily, I am guessing, I had not locked the (vacuum-operated) doors.
So, at the moment this is a rhetorical question. This is not the best
neighborhood, so ideally I should lock the car. But if I lock the
doors and the battery goes out again, how can I unlock them again? Or
is the battery not related to the vacuum system, and I need not be
Thanks for any comments.