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I understand that you are new.
But that's way to complicated a problem to get any useful input without far more details.
Having said that, and hoping you're not a troll..
My first guess, and it's strictly a guess since there's no information at all, is it was not replaced properly and probably still has air in the module.
Whoever installed it would need HD's Digital Technician II to (program the ECU, the counterpart of the HCU on ABS module) do a module replacement, whether it be ECM, BCM, or ABS Control module.
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