[ajp166]

Guys I keep getting this and when unlocking the vehicle lights don't go on due to this problem. Shall I get a new battery?

 

[HPIA4v2]

Guys I keep getting this and when unlocking the vehicle lights don't go on due to this problem. Shall I get a new battery?

I just replaced mine last month, initially I got intermittent excessive draw while engine off and listening to radio in spring, then I've got to park the X6 outside (usually I park in the garage unlock) then boom, can't start the car the next day.
Replace with AGM battery, exact size and need to re-register it so the "SMART" alternator won't over charge the new batt

 

[ajp166]

SMART alternator? whats the smart part about?

 

[HPIA4v2]

SMART alternator? whats the smart part about?

Most BMW after 2007 and on, has charging algorithm based on time, i.e the alternator will charge the batt at higher rate overtime among other criteria. That's why once you change teh batt it's recommended to reset this charging profile to avoid over-charging brand new batt (the alternator still thinks it's dealing with 7-yr batt otherwise)

 

[Doug Huffman]

SMART alternator? whats the smart part about?

The 'smart' part is the Intelligent Battery Sensor on the positive pole of the AGM battery. AGM batteries have peculiar charging requirements for best life capacity. Not the slightest overcharge. Never charged > 14.8 VDC. Never rapid charged.

The IBS communicates with the DDE ECU which regulates the alternator and engine, and in extremis most of the convenience loads.