Did this refurbished Bosch alternator come in a Bosch box or a plain cardboard box? Exactly who rebuilt this? It is certainly suspect from the symptoms.

One other thing I would try, is to get one of those battery post cleaners. Use the cone shaped brush on the cables, and the post brush on the posts. Them make sure you get the cables on tight. Tap them down with a small ball peen before tightening so you get good contact. I'd also clean and resecure the connections to the alternator.

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2014 BMW 328i Xdrive
2011 BMW 335i M-Sport
2008 BMW X5 4.8i Sport
2000 BMW 528i 5sp