While driving, my vehicle suddenly shut down in the middle of traffic without any prior warning. I was left stranded in the hot sun, fearing for my safety and praying that I wouldnat be rear-ended. The incident was not only terrifying but also unacceptable for a vehicle of this caliber. I contact Mercedes customer service. I spoke to a representative name Stephanie. She called the Mercedes dealership service department in Columbus, Ga and received confirmation that my car did shut completely down on me without warning. Stephanie stated she will notate the incident. I told her there should be more than just a notation because this put me in grave danger, not only was my life in jeopardy this is a serious potential threat to others.