I think we are basically in agreement but not everyone has the capability to repair cars themselves. It is tough to ask a novice to first diagnose, then replace-repair a problem with a vehicle if they don't even have a rudimentary understanding of what they are attempting. A trip to a Mercedes dealership may be cost effective for someone likethat.
What are you using that gives you live data as I will get one for myself.
The VW can-bus scanners that I have do all systems, air-bags, theft, HVAC etc as well as plotting, graphing, storing live data paramaeters. They cost less than $100 and do everything a stealership can do. I don't know of anything like this for our crossfires at that low of a cost. If they are out there let me know where I can get one, or the software for my laptop along with any special cable needed for the mercedes application.
Thanks

I just looked at the Ultragauge website. It does appear that most all the live parameters you would need for troubleshooting are available. I will probably order one if I can't find something more comprehensive at a reasonable price.