Defect
On certain 3-series and M3 vehicles, the positive battery cable connection to the fuse box may fail. This could cause a loss of electrical power while driving. As a result the engine could turn off and various electrical systems may not work, including the lights.
Safety Risk
A sudden loss of engine power and/or loss of vehicle electrical systems could increase the risk of a crash.
Remedy
BMW will notify owners by mail and instruct them to take their vehicle to a dealer to replace the positive battery cable connector with an updated version. Note: This is an expansion of recall 2013-048.