IBS 3-pin BSD/LIN Connector Location
They're very small wires for the BSD/LIN connection to the IBS. It is very possible you accidently damaged it when changing out your battery. The wires are like 22 AWG thickness--small, and easily broken.
This IBS connection, #3, it important for the charging strategy of the battery. This is the same LIN connection that the DME connects to for things like the oil level sensor, alternator.... The connector is X13895.
You should find that little blue connector on the wire harness closes to the negative battery terminal. It should be attached right around the area of the right rear tail light harness area.
Please report back your findings.
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2008 BMW M3 E93 MT
R135
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