I know someone with a 2017 540 that had 5 wires, I bet it is tied to build date. My build date is December 2017.
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2018 M550ix|Carbon Black|Dinan Modifications|2003 540i|Jet Black|M-Sport|2021 X5 Mineral White
Prior BMW's: 1987 325e|1993 740i|1998 740il|2001 530i|2002 745li|2007 750li|2006 750li|2001 530i|2012 535xi|
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