I recently had my trip computer changed out due to an overnight reset problem. The computer wouldn't hold the date or average MPG. After changing by the dealer two times, the new computer will not record average MPG after being reset.

The newly installed one ihas a different part number, which the dealer claims is the new replacement. He borrowed one from an older ML (the same part as the old one) and it worked fine.

The dealer says that Mercedes obviously dropped that function with the newer computer and live with it.

Does anybody have any information?

Thanks in advance.