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I own a 2007 SLK280 with approximately 60,000 miles on it. It's been serviced regularly. I've never had any problems with this car. I'd driven home from work (approximately 40 miles) on a major highway, at speeds between 75-85 mph. I came to a full stop after exiting the toll plaza and heard a subtle pop come from under the hood. My car then immediately went into limp mode and the check engine light came on. I've done some research and it appears the problem might be a transmission solenoid. Anyone with experience willing to share some information? Does that sound like it might be the problem? Cost of repair?

Thanks!