BCM and RCM are in the box next to the battery. Every RCM in all Crossfires, SLK320s and SLK230s are the same, cept the SLK230 RCM is about $45 cheaper but has all 15 amp fuses, one of our fuses has to be 20 amp - so I ordered an SLK230 RCM and transplanted the fuse.

BCMs dont go bad, I'd not concern myself with the BCM unless it is proven the BCM is bad. And Iv'e been here since 2009 and can think of maybe ONE BCM that failed.





In the SLK230, the yellow fuse is blue, our cars need a 20 amp (Yellow) fuse, there is no other difference in the RCMs between the '320 and '230.