BMW 428I 2015–2016 — technical service bulletin
Bulletin B510115 · NHTSA communication 10147674 · issued Mar 1, 2015
Technical service bulletin
communication type
Equipment Adaptive/mobility
component
2015–2016
model years
4
vehicle entries
Official summary
Harman Kardon Surround Sound System Noise. The customer may complain of a groaning/grinding noise in the area of the rear speakers. Lack of clearance between the tweeter and the mounting contact and/or wires.
Vehicles covered
What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.