Sounds like the ABS module is due for a rebuild, but I would first go on Bimmerforums and look up posts by Bluebee on "abs trifecta" and read through the entire troubleshooting thread, basically shows you how to test all 4 wheel sensors, test the ABS module itself, etc.

Your indy should be able to see what faults the ABS module is throwing as well, but your alternator sounds like its fine to me from the voltage you list.

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2018 Ram 2500 6.7L Cummins 68RFE
19k miles -Bright White/Black - Big Horn Sport - Crew Cab Short Bed
2013 X5 35D (CEO's) - Born on 5/17/2013 -
82k miles - Alpine White/Cinnamon Brown/Premium Pkg, Sport Activity/Premium Pkg and Sound/20" Style 214/Running Boards