Quote Originally Posted by rebel.ranter View Post
The duty cycle in BMWs from the mid ‘00s are very heavy and BMW slowly made the move to AGM batteries in order to find a better way to handle that. The other problem they didn’t solve was the “unfavourable driving profile” rubbish. Irrespective of whether the car has a Lead Acid or Absorbed Glass Mat battery if the car is only driven short journeys there is not of a recovery charge to bring the battery back up to where it was. Over time the battery gets weak as a result.

If you are replacing a like for like battery, i.e. the same Ah rating and AGM for AGM then the battery only needs to be registered.

If you change the Ah rating or move from AGM to Lead Acid them you need to code the CAS (VO Code CAS/LMA first then “Default Code” the CAS). This is so the correct charging profile is applied to your new battery.

I hope you are doing well SD_Dracula, I think it was 7-8 years ago since I saw you last? I’m still thinking back to the cruise control on that 1 Series back then, I should have just VO coded in cruise control & default coded the replacement unit and it would have worked! I was too chicken back then!
Wow, that long? That cruise control thing never worked in the end, brought the car to Bloomfield and they hooked up one of the proper tools to it, enabled everything but just didn't take, the steering wheel unit might have been the fault.
Still got that 630i?
In the end replaced the battery with a new AGM one from Frank Keane (actually surprised that it came in cheaper than 3rd party battery) and got it coded by a garage that did an oil change also.