my e300d had a wire on the W terminal of the alternator connected to a AC voltage lamp and then a flip switch - I have no idea why would anyone want to do that, the W terminal in Bosch alternators is a tap into the internal windings before the diode bridge.

Same weird car had wire nut repairs on 3 wires in the engine room.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)