There's probably only one solution to this problem at this point. Take this car to a goob mb tech! Don't waste anymore time with self diagnosis or frustration. I had to pay $1000 just to have my benz shipped here from OK. $225 doesn't sound so bad. If no one else offers any suggestions closer, I would take it to Roy Fields in Hunt Valley, md. They are the best alternative to a dealer I have ever found! And cheaper than the dealer. They found a short in my car in 1/2 hour! Shorts can be costly and hard to find. Their number is 410-527-1010. Just get it done and over with or sell it but I wouldn't do anymore guessing about it. It can be very frustrating.