I have a 1999 ML 430 approx 98k miles. I'm on my 3rd alternator and 4th battery. I live in a region where it gets up to 100 degrees - 104 degrees in July, Aug, Sept time frame. It seems that whenever it get's hot, the car won't start. Actually, it will start in the morning, you drive 3 miles, stop, then it won't start. Obviously, the battery and alternator have been replaced multiple times but I have a feeling that the mechanics are treating the syptom and not the cause. I have checked the charge on each battery prior to replacement and they have been dead.

Thoughts anyone?