Hello, what do you mean by "reset the radio"? What is wrong with the radio?
You might need to visit a shop near you that has a technician you can speak to directly to get some opinion or guidance.
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Click the link or call us at 877-913-1554. We'll gladly find you a certified RepairPal shop in your area.
RepairPal Certified shops can diagnose and repair your 2011 Mercedes-Benz C350. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.