While driving on an interstate highway, I received a yellow "48V Battery malfunction" notice. Because this battery had failed before, I had read on internet forums that the car could just stop working, so I took the next exit (about 3-4 miles). At the top of the ramp, I had a red "Battery Malfunction" (red=stop driving); then, within 15 seconds the car had no power and gave me a critical "engine overheated" message. I was able to coast into a parking lot. Had I not exited, the loss of power would have likely resulted in an accident and we could have been killed. I believe the battery powers the water pump (amongst other things) and that caused the engine to overheat and shut down - but with no warning of overheating. This is the second time the battery has failed - first at 15 months and approx 17,000 miles. I had to wait 3 1/2 months for a new battery (they can't keep up with demand - this tells me the problem is widespread) ) and now around 22,000 miles and 5 months after getting the new battery. A review of the MB internet forums shows this problem is pervasive in Mercedes models that use the 48V batteries and I believe this is extremely dangerous - if I hadn't already been aware of the issue from the previous failure, I wouldn't have known to exit the interstate before the car failed and could easily have been badly injured or even killed in a collision.

- Holly Springs, NC, USA