The modern BMW - and a lot of other vehicles - have Intelligent Battery Sensors. The IBS monitors battery performance and is supposed to optimize battery charging as the battery ages which may lengthen battery life. I suspect that it also helps them attain fuel economy targets.

A new battery, at a minimum, needs to be registered which simply tells the sensor that a new battery has been installed.

If the battery type is changed, i.e., AGM to/from FLA, the battery must also be programmed.

If a battery with a different capacity is installed, the new battery must also be coded.

You don't have to perform these steps to get a new battery installed and your BMW up and running but it probably doesn't help the new battery last as long as it could.

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8/2011 X5 xDrive35d Sport, Black Sapphire Metallic, Black Nevada Leather, Fine Burr Walnut Trim
2/2001 M5, Jet Black, Exclusive Complete Black Walk Nappa Point Heritage Leather, Black Cubic Trim