Has a problem this week with the battery being drained and the person at Batteries and Bulbs said around '04/'05'/'06, BMW require replacement batteries to be "registered" with BMW. He said if a battery was replaced and not registered the car would assume it was an older battery and increase the charge which with a new battery would cause overcharging. Is this true and what must one do to effect it? And before anyone questions the wisdom of someone at B&B I will say they have been nothing but helpful. Have only purchased two batteries from them yet they replaced the battery with a new one at no charge.
I don't think E46's require battery registration - I believe the first 3's requiring that were the E9X's.