DJ does not check in here often. But the answers to your questions have been known for years. The RCM used in the Crossfire was used in the SLK320, SLK32 and I-dont-know-how-many others. It's a simple failure of an inexpensive module and their fix was easy: Replace the module.

ANd as long as it was Mercedes only, it was no big deal. Any MB dealer service department that had a problem diagnosing electrical issues (and all of them did, 'mechanics' and "techs" are not trained in electrical diagnosis) could reach out to MB and get help. But the problem is, our cars have no such support - no Chrysler dealer knows anything about them. THAT is the problem, dealers can't fix anything because they have no support. Im sure that IF you could get an MB garage to look at the car, they'd recognize what is going on since they've seen it before.

It's a cheap part, readily available and the fact you can get RCMs from several sources proves that there are TONS more cars out there other than the Crossfire that need these. My Ford Ranger cost me almost $1,000 for a new fuel pump and tow to the dealer, it is what it is. A $150 module is no big deal.