0493625 126413 Guard MP
WARNING: This page is about a different car, the 2011 BMW 528i. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
(Reverse polarity protection) Retrofit kit with reverse polarity protection diode for installation into adapter cable 12 6 411, to adjust it to performance data of switching device 12 6 050. Identification: Red heat-shrink tubing Only available as part of complete tool set 12 6 410 - (83 30 0 491 148).