e39 M5 Randomly shut off while driving

[EsE39]

Hello,

Looking for any insight as to why my m5 randomly shuts off while driving. The first time it happened I was on the highway and the motor just shut off so I pulled over started the car with no problem and drove for another 30 miles. Second time I came to a stop light and everything shut off including the battery. I couldn't even turn on my hazard lights for the cars behind me because I had absolutely no electricity running through the car. So I got out and looked at the battery thinking it was a loose connection but everything looked secure. I went back into my car and after a couple minutes everything powered up again and drove home with no issues.

The only thing I can think of is a loose battery connection but that wasn't the case. Maybe a bad sensor?

[SSharo]

Checked for codes? Any warning messages?

[cgl]

Hello,

Looking for any insight as to why my m5 randomly shuts off while driving. The first time it happened I was on the highway and the motor just shut off so I pulled over started the car with no problem and drove for another 30 miles. Second time I came to a stop light and everything shut off including the battery. I couldn't even turn on my hazard lights for the cars behind me because I had absolutely no electricity running through the car. So I got out and looked at the battery thinking it was a loose connection but everything looked secure. I went back into my car and after a couple minutes everything powered up again and drove home with no issues.

The only thing I can think of is a loose battery connection but that wasn't the case. Maybe a bad sensor?

Same thing happened to my 2003 M5 a month ago. The car just suddenly die (lost of electrical power with blackout navigation screen) while driving. Pulled over and stopped at the curb and opened the rear trunk (no trunk lights) and while opening the battery cover, the lights and power just came back on suddenly by itself. This happened a few more times the next day. Finally disconnected the battery terminal and used battery terminal cleaning tool and thoroughly cleaned the terminals and reinstalled. No problem since the cleaning.