Vehicle automatically locked leaving my 3 year old in the vehicle strapped to her carseat. The key fob was in the vehicle at the time. My wife left the keys in her purse since they are bluetooth keys and placed them inside the vehicle and walked around to drivers side to get in. Vehicle self locked while she was walking around to driver's side, leaving child trapped in vehicle in 100 degree weather. Called Mercedes Benz of amercia, relayed the problem. Phone rep "[xxx]" said this happens from time to time and "they" do not know why. Talked to Mercedes Benz of san antonio, tx. They said they have never heard of this happening and said it would be a $130 diagnostic charge to analyze the problem. Was informed at time of purchase of vehicle it was impossible to lock keys in vehicle unless lock button is depressed on keyless start key fob. This is a mfg defect in my opinion and mb of usa needs to fix this problem before a death occurs. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6).

- San Antonio, TX, USA