My friend's 325i has had battery drain problems. In looking into it (my first time working on a BMW...I'm a weekend, admittedly mostly American Car basic mechanic), I noticed the lock cylinder was going, as it twisted past the off position.
While starting the process of chasing down the drain (I didn't get far, just charged up the battery, cleaned cables, etc) I went to start the car and the key just spun to the right.
So, I must replace, as miniumum, the lock cylinder, which, in looking at the manual and some web sites, seems to be within my range of skills. However, questions before I did into it:
1. This has the security system. If I buy a lock cylinder, with new key, how do I get the key matched to the car?
2. Should I automatically replace the igniition switch as well while I"m in there?
Thanks for your help!