Where does the small diameter wire that hooks up to the positive battery terminal connect to? It is tied up with the gigantic positive cable.
I had to swap in a battery into my M3 which is bigger than my standard battery, so I was unable to use my normal tie-down bracket. As my luck would have it, the battery moved around enough to chafe through the shielding on the smaller diameter positive wire, causing lots of sparks in the trunk and lots of swearing on my part.
Looking at the diagram on realOEM, it looks like it ties into the positive terminal block under the hood? The wire is munched part-way through, so I'm wondering if I should just crimp/solder a new section on, or replace the whole thing. Things seem to work just fine after I taped up the offending area, but I'd rather not have an issue down the road if the tape wears through.