I received the iCarSoft MB II tool and updated it to current version software early this morning. The codes I get from it are:

U103888

and a separate message that "B1-S1 Sensor Heater Fail"
0.001V Actual, 0.110V Max

Any suggestions appreciated on what this points to as an issue on my 2014 E250 Bluetec 4Matic @ 102,000 miles. The car drives as normal with no apparent problems.

Thank you,
Ken

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2014 E250 Bluetec 4-Matic
2014 GL350 Bluetec 4-Matic
1996 Chevy Tahoe 4 x 4
2009 ML350 (sold)
2005 SLK350 (sold)
1999 E300 Turbodiesel (sold)
1998 ML320 (sold)
1991 300D 2.5 Turbodiesel (sold)