Em63

Hi all, I own a 2016 E250 BlueTEC with 97,000 miles and yesterday as I was leaving a friend's house the car failed to start. I've owned it for about 9 months now and have put almost 8,000 miles on it since buying it. Services include a new fuel filter, Cabin air filter, two oil changes, new tires, the normal stuff. This E250 does have a handheld tune (for efficiency) and a DEF delete all done by the previous owner who I have known for years, and the vehicle has been meticulously serviced. I tried trickle charging it, jumping it off, as well as replacing the battery all together. The car tries to turn over but won't even make a full rotation, I took it to a local Mercedes specialist (I am in college and can't bring it to the nearest dealer 100 miles away) and he said the engine is either seized or the starter has gone bad, I don't believe this because I was driving the car all day and only was at that friend's house for an hour, it was still hot. The previous owner said they read something about a popped module in the fuse box, but I could not find a lot of information on it. The specialist has yet to hook it up to star, so I haven't received any readings yet. Has anyone seen an issue like this?

Update: The issue that caused the lack of a complete rotation during start was that the alternator was locked up. The local Mercedes specialist had misdiagnosed the issue, and I was finally able to get an appointment at the dealership. $3,400 dollars later and the car was fixed as of December 2023. I sold it immediately as I had lost the equity I had in the car and the used market has been souring for a while. Overall, the ownership experience was pleasant up until that point. I would recommend an E250 BlueTEC if you were driving mainly long distances as the MPG is hard to beat but be prepared to shell out money as in my experience independent Mercedes mechanics won't touch a diesel and she'll need to visit the dealer.