Case Studies

Tech Tip – BMW and Mini Battery Registration (Replacement)

The electrical system in late-model Minis and BMWs is quite sophisticated, in that it tailors charging as closely as possible to both the type and age of the battery. The Engine Management computer also controls the alternator output. When replacing a battery, this computer needs to be informed if you’ve replaced the battery or updated the vehicle from a conventional Lead Acid battery to an Absorbent Glass Mat (AGM) type; it charges the AGM differently than a traditional battery.

This process of updating the alternator-control computer is called Battery Registration. Ignoring the registration process after replacing a battery won’t necessarily trigger a Diagnostic Trouble Code or Malfunction Indicator Lamp (‘Check Engine’ or ‘Service Engine Soon’ light). However, be advised that skipping the battery registration process can dramatically shorten the life of a battery in these vehicles and- worse yet- damage components within the entire electrical system.

We have diagnosed some BMWs with failing batteries, some installed less than a year, simply due to failing to have the battery registered! The charging system often shortens the life of an unregistered battery by charging it too aggressively, especially when it is cold, and sometimes damaging other control units. At times, we have replaced an alternator that failed prematurely because battery registration was not performed when the vehicle’s battery was replaced.

Battery Registration informs the vehicle that the battery has been replaced. It completes the following operations:
· Battery capacity is set to 80%
· Current Odometer reading are stored
· Stored battery statistics (current, voltage, battery charge level) are deleted
· Stored temperature statistics are deleted

The following late-model vehicles require battery registration:
· 2002 and newer 7-Series E65/E66 chassis
· 2003 and newer 6-Series E54/E63 chassis
· 2004 and newer 5-Series E60/E61 chassis
· 2006 and newer 3-Series E90/E91/E92/E93 chassis
· 2005 and newer X5 E53 chassis with N62 engine
· 2007 and newer X5 E70 chassis
· 2008 and newer X6 E71 chassis
· 2007 and newer Mini Coopers (R56)

Don’t take the chance, always have a new battery registered after installation at a BMW-qualified shop- it’s not expensive and will ensure a properly operating electrical system. At Atlantic Motorcar, we have the equipment and the training to properly register your vehicle’s battery to factory specs, ensuring that manufacturer warranty requirements have been met.

On a final note, you can expect your original or quality replacement BMW battery to last 4-8 years in a properly operating BMW, and 5-10 years with an AGM battery.

Peace of Mind, that’s what we do.
Atlantic Motorcar Center Service (207) 882-9969