I suggest starting with having the battery load tested and to unlock the cluster and monitor real time voltage. 14.8v is high. BMWs are very sensitive to low or excess voltage with the result being all kinds of weird things can happen. In addition, when fluid is added to the transmission it should be filled to the point a small stream runs out and then with the engine running run through the gears, then drive it enough to bring the fluid temperature to operating and then check it again and top it off as needed. All done with vehicle level.

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas