Well funny that you should mention that. I now have the battery light on, which means a charging problem. I called several BMW dismantlers and local shops. They told me that this cannot be rebuilt. I am like you and have to buy one from somewhere else. The only way out of this pickle is replace it from a dismantler or retailer. I am going to buy on from Ebay. My light when out when the alternator is replaced and battery is charged. I think that my coolant leaking problem (valley pan) may have something to do with it because it is water cooled.