A
Anonymous
Guest
After I purchased my Z4 3.0 2003 I noticed the red light 'battery not charging' coming on every so often after starting. I discovered the battery fitted to the car was a General Motors 55Ah instead of the required 75 Ah. This smaller battery was also causing the roof to not lower at times, as if the system was attempting to conserve power. After fitting a brand new battery of the required spec the problems have not returned.
