It takes a good amount of driving to charge but takes many months to self drain.

You would have to cut open to determine if the battery is charging and it's tough to determine what contacts may be shot.
My fob is screwed together so I'll probably open up to Repair but I've been planning to replace my lost key before doing this in case I killed the immobilizer chip but I can maybe open to take a photo to show you.


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2011 E70 • N55 (me)
2012 E70 • N63 (wife)